Hey guys, Ken Ross here, and I'm a business consultant that specializes in reducing costs for businesses by looking at their essential expenses And today I'm a little excited today because I want to talk about a topic that you may not have heard of before But it's called hurry sickness. Now. What is hurry sickness? You may think is this a real disease? Can you sound kind of crazy and maybe I do sound a little crazy But it isn't a real disease and it is something that is a psychological phenomenon It was originally derived by cardiologists in 1974 And it is something that has been studied over the years and kind of spent some time Looking into myself. So if you're so inclined check the description of this video I have a couple resources here for you to kind of help you put a little bit more meat to what I'm about to say But what I want to try to describe is what hurry sickness is and What you can do about it because honestly, I feel like it's busy at business owners. We're constantly busy doing a lot of things we want to Perfect what it is. We're trying to do we want to make the most money or we want to help the most people By being effective leaders and by completing the tasks that we have But if we get stuck or we get bogged down into this idea that we are going to have to hurry through things Then you could have hurry sickness. So let's talk about it First thing I want to talk about is kind of what it is, right? And maybe some of the symptoms of this illness, right? Hurry sickness really drives kind of two two things and that's anxiety You know feeling anxious that that that spot in your in your stomach or in your heart That's like man. I got to get this stuff done and I'm I'm a little just nervous like just uneasy and this idea That we have to hustle through everything then there is not enough time in the day those two components put together and kind of in this cycle Exastribate hurry sickness the next thing I want to talk about are some of the aspects of hurry sickness now Before I really get into this list. I want to give you a caveat not everything in this list Exclusively means you have hurry sickness. Think about this list as an all-inclusive list And if you have a good number of these symptoms then you probably have hurry sickness And that's something we should really want to invest some time in dealing with so let's get into it The first thing I want to talk about is this idea that everything is a race every task Every thing you're trying to do when you get up in the morning. You got to get ready. You got to get out the door Everything is a race now. I'm not saying that There aren't times where you want to hurry and get things done and and and you have a time constraint But you look at it as a competition. You measure yourself on it or you or you internally Process it as I have to win this I have to get this done as fast as I possibly can That's what I'm talking about the next thing I want to bring up is tasks and how you complete them If you have troubles trying to complete Individual tasks without other tasks getting in the way of that then that may be a sign that you have hurry sickness too I can give you a good example. Let's say for instance, you're trying to finish a a very important report of your finances and in the middle of trying to do those finances you are Just stressing out about some aspect of your marketing campaign And you go back and forth between these two things and they they they're so intertwined that you can't separate the two and just complete One task and then complete the other that may be a sign That you're bogged down with too many tasks and you're you're in this hurry sickness mentality Something you should really be aware The next thing I want to talk about our delays Every business every person Whether it's a business or not every person experiences a delay in their day in some sense People have to be willing to be patient and Understand that life happens But the lays that equal being so irritable that you're just unable to deal with that irritability That is a sign of hurry sickness. I do have those moments where I feel like this is just too much for me I can't I can't handle another delay on this task Or I can't handle another delay to getting getting through this milestone or reaching this bar Those types of delays if that's constant in your in your life If that's something that constantly comes up is hey even a little delay Causes some irritability and puts you in this place of I have to get this done faster and these delays can't exist I'm gonna fail if I don't get it done right now then you may need to look into Some of the steps. I'm gonna give you later in this video on how to deal with hurry sickness Next thing I want to talk about is being behind schedule You constantly think if you're in a hurry sickness mode that you're behind schedule But the next thing that leads to the next thing that leads to the next thing are always behind something that I don't think I've really experienced myself personally, but I do experience times being behind schedule not having things Well thought out for the day and being in this mindset But how do I how do I fix my schedule how to get it get it figured out so that I can I can get through the rest of my Day and get my tasks done if that is something that is constant in your life That is always happening, then you may be experiencing hurry sickness as well Okay, the the next thing is one that I know I definitely don't like Personally, this is a this is a trigger thing for me You know how when you're in conversations with people and you're having a great Conversation or or maybe even you're having a great great discussion a debate back and forth and the person you're talking to interrupts you mid-sentence. Yes interrupting people is something I Absolutely cannot stand as a as a professional I love to take turns and and and debate a topic or even have a conversation but if we can't take turns and You're constantly in a state where you have to interrupt someone in conversation then you are in a hurry To get the conversation over with to get to the next thing and that may be hurry sickness And so not not to say that I'm going to call everyone out for interrupting me But I really didn't feel like a lot of people that's where they're at They're so anxious to get something done that they are willing to interrupt you And that is something at least I've started to give a lot of people more grace about us in the say Well, maybe they just have some anxiety or maybe they really want to get this done and I really want to have The right discussion I want to get to the bottom of what it is that I want to do so in a lot of those times I do I try to show a little bit more grace because hey, this this is an important thing for people's mental health Okay, the last thing and This is what I know. I've experienced a lot of people who are in this especially Having worked for three fortune 500 companies work with a lot of different types of managers It's something I definitely know at the railroad is something that people love to do and that's checking things off of their to-do list We used to have lists at the railroad I worked for them where we would show people our list of to-dos and say yep Did this this week did this thing this week fill it out put a date on it write notes Those types of things they are very good to keep organized and to stay on task But if you are so obsessed with checking things off on your to-do list and you are constantly looking over these things Obsessing over them, then you may have hurry sickness. It's something that I know for myself as a professional I I know that you know staying on task is important I know that having a good list of things to measure gets is important but you cannot overweigh the importance of that list when it comes to Doing the tasks and doing them well and that not cause a lot of stress and anxiety Hurry sickness is a real thing these six things that I mentioned They're all really important and they're all things that can happen to us or have happened to us in our professional careers But as a business owner if you have all of these things you really need to invest in some time in yourself and understanding how to deal with the anxiety and the frustration of This illness so let's get into that part Okay Couple of quick tips here on what it is you can do and like I said Please check the resources that I have in the description below really helps you give more information Really good insight into what this is what I'm talking about I really do think as business owners or as a as people in general we live in very Interesting times we live in times where not everything is is Is back to normal not everything is is together? So people are really anxious so that anxiety Combined with the culture that we have here in the United States or in North America or in the world even I would say that those two things would would put people in more of this category of I could have hurry sickness because hey, I just have to get these things done and we're in so much anxious times with Hyperinflation here, right? What do we do anyway? Here are some tips on how to Put together a good strategy to deal with hurry sickness First thing you really want to do is you want to prioritize your tasks, right? So this kind of is one that I know is important to me and I constantly stressed it in in my career And IT it's what is the top priority because everybody wants everything done right away and everybody wants something done very well But not everybody wants to be patient and wait the time that it takes to get that stuff done So they're constantly trying to assert priority, right? Prioritization is very important that you stick to what the higher priority tasks are at the time and that the lower priority tasks can go I'm not saying I'm noticed just Document it and say hey look I got to leave those for later Please invest time in prioritizing tasks knowing when things are due Understanding like hey, this is important now and this is important later if we have time we can do these things Prioritization is something I think people can invest a little bit more time in and it would make their life a lot easier The next thing I want to talk about is something I've talked about in a lot and a lot of different ways in on this channel and it involves Self-care involves getting yourself the proper rest Mentally as well as physically Emotionally spiritually so that you can take care of yourself self-care is one of those things I think as a business owner even as people in society today, especially given the times that I keep talking about Right, we don't take enough time to invest in ourselves To make sure we're in a good headspace in a good place to actually complete tasks Or to be able to focus on the tasks that we're doing so that we can do those things efficiently So that is something I think would really combat against Hurry sickness if you invest enough time in yourself and what it is that you're trying to do Emotionally and be at a good place centered there emotionally then these tasks aren't so overwhelming The level of anxiety that you have is a soul overwhelming your physical fatigue or whatever it is that you're you're Experiencing physically won't get in the way of your mental Processing so that you can get things done something. I really think a lot of folks should should invest some time looking into The next thing is routine now you may think oh why have a routine, right? Why always try to be so consistent with certain things you don't have to have a routine for everything But you should have a routine for for some things Establish a decent bedtime routine Study some good books maybe and invest in In reading right at night and say hey look when I go to bed or when I get ready to wind down for the day I'm going to read five pages of this business journal or these I'm going to I'm going to read the Wall Street Journal. I'm going to do something to invest in myself and kind of Center myself around what it is. I'm trying to do and then Go into the the next day knowing. Hey, I completed a day Because I finished these routine things that I do at the end of the day to know that the next day I'm centered. I'm in a good spot Okay, the next thing really kind of has to deal with Planning because if you don't have a plan right you plan to fail So you need to plan time to think about Your strategy to think about how to tackle the day or even midday, right? Let's say you you don't you struggle with Having a consistent lunch break for instance or having consistent breaks for that matter, right? If you could just schedule a consistent time where you're like at this particular moment in my day I'm going to stop for 15 minutes. I'm going to think about where I'm at I'm going to debrief myself or even my staff on where we're at In the day and say these things are now priority or these things are now more important If you schedule that that will do wonders to Keep a good routine Even if you don't have a good routine if I if I'm making any sense The fact that you could schedule time to just think about what it is you're doing What you're trying to accomplish will go a long way in making sure that you Can operate your business effectively that you can even just handle yourself for that matter Not just your business, but yourself in a manner that is Very controlled and measured so that you can be effective and get things done So something I really think a lot of people should spend some time doing Spend time every day thinking Okay, the last one really important right talked about What it takes to to have hurry sickness and there's something I really haven't addressed In great detail right and that's anxiety if you're so stressed out or you have so much anxiety that it's Controlling you that is physically making you sick or that's making you ill in a lot of ways and it keeps your mind So busy that you can no longer process other things Then you have a problem where you need to seek support and professional help You need to deal with that stress and anxiety. That is Probably top priority. I know I mentioned this last but I really think it's very much important if the anxiety didn't exist I think the pressure of the tasks and the in the The idea that you have to get so many things done would Kind of melt away because you would be able to look at those tasks realistically. You'd be able to prioritize them better I think anxiety or an emotional stress Puts a lot of toll on people and makes them want to push even harder for something that they can achieve That way they can they can achieve it better if they didn't have the anxiety there in the first place So if you can remove anxiety and stress from your life and you need to seek professional help It's something I really think people should spend more time investing in and know like I said and I've mentioned this a few times already in this video that COVID and and all the things that happen politically or even just things that happen in people's family life or You know stresses of of Material things those things contribute to so much stress and anxiety in people's lives That really affects their performance and what they're trying to do and I I can't stress it enough. I know I've experienced that myself in this time. I don't think anyone Who's gone through COVID or gone through this global pandemic could could say I came away unscathed I Hurry sickness is something that's real Right and as as much as it's just a psychological phenomenon like I mentioned the beginning of this It's psychologically something that we don't fully understand yet and Having a name for it at least for me gives me this idea of the sense that I can actually identify it And now that I can identify it. I can have a strategy to go forward and not have to deal with that Anxiety and stress or that stressor in my life that unknown Thing right that's really irking me if I hate to I hate to use the cliche if I can name it and claim it right But but that's really how I feel. I feel like the fact that I can give it a name helps me understand Okay, I'm having hurry sickness or maybe I'm having early signs of it that I can go back and say Let me invest some time and just thinking right now Let me just do this and that will get that will take that feeling away that will help the situation dramatically Okay, guys, that's what I have for today. Thank you for your time and attention to this a lot of information There I wanted to give you but really think it's important that we have a great conversation and discussion about it Please post in the comment section below and what you think about hurry sickness Is it something that you think you've actually had to deal with and how you've dealt with it in the past? I'd love to have a conversation with you. I'd love to inspire others to raise awareness to this idea of this thought that anxiety along with this stress and Aggravation of wanting to get things done could could lead to such a A an illness mentally that can put you in a very bad bad place as a business owner, so please Let's let's have a conversation in the comment section below And also if you haven't had a chance like and share this video with your friends Subscribe to my channel and visit my website. I am ken ross.com until I see you next time I'll see you around


Modern technology has made the operation of wheeled vehicles so easy that many people tend to take the vehicle for granted. Actually, all vehicles can be broken down into several systems, each performing a separate task, yet complimenting each other to make the vehicle perform smoothly. If all the systems in a vehicle were listed in their order of importance, the brake system would have to be one of the systems near the top of the list. As a wheeled vehicle mechanic, it is important to remember that the quality of any brake service is always measured in terms of safety. To effectively troubleshoot and perform brake system maintenance, it is essential to have an understanding of basic hydraulic principles. The engine will get a wheeled vehicle rolling, but it takes brakes to stop it. In today's army, hydraulic brake systems are common, and among those the ones you're likely to see most often are the drum brake systems used on M151s, the 1.25 tonne 4x4 utility vehicle the army has so many of. But there's also another type you need to know about, the M880 1.25 tonne cargo truck uses drum brakes in the rear, but up front it has a disc brake system. As a wheeled vehicle mechanic, you've got a lot of personal interest in making sure those brakes are working, because the vehicle whose brakes you maintain or repair, you've got to road test. It's up to you to put safe brake system operation at the top of your list anytime you work on hydraulic brakes of any kind. The safe operation of a vehicle and somebody's neck, even your own, could be at stake. For that reason, we'll concentrate on what you need to know about hydraulic brake systems, what they look like and how they operate to help you maintain, troubleshoot and repair them efficiently and safely. When you have viewed this program, you should be able to understand the basic principles of hydraulic brake systems. You should be able to identify the components of the drum brake system used in the M151 and understand its principles of operation. You should also be able to identify the components of a disc brake system, like that used in the M880 and understand its principles of operation. In part one of this program, we'll discuss basic principles of hydraulic brake systems that apply to both types of brakes, and then discuss the drum brake system used on the M151 vehicle. Part two will cover the disc brake system used on the M880 series vehicle. Get a good grip on the basic principles and you'll be in good shape to maintain brakes or troubleshoot and repair any hydraulic brake system you're working on. First let's look at basic principles of hydraulic systems because these control everything that happens in hydraulic brake systems. Under normal pressures, liquid cannot be compressed. This heavy weight, for example, cannot press the liquid down beyond its original level. It is, however, putting force on the liquid. This force acts in all directions, putting pressure on the weight itself and on the walls and floor of the container. The pressure is the same at all points. Another thing about liquid is that it occupies the entire volume of the container, filling every space no matter what its shape. This mock-up has a weight in each cylinder and will call these pistons like those you'd find in a hydraulic brake system. Let's watch what happens if we push down on one of the pistons, putting extra force on the liquid. The liquid is non-compressible, so its volume remains the same. The effect is to transfer the force to the second cylinder where it acts on all surfaces, but only the piston is free to move and so it rises. Now we can see another important principle of hydraulics. The area of each piston is the same, so the right-hand piston rises by as much as the left-hand piston is pushed down. That's because the pressure is the same on the face of both pistons. Let's see what happens if one piston is bigger than the other. The small piston puts a certain amount of force on the liquid. At the larger piston, this same force acts on each area that's the same size as the small piston, so the pressure on the face of the large piston is multiplied by that amount. This means the force applied by one piston can be multiplied many times just by enlarging the area of other pistons in the system. One other thing happens. The smaller piston has to travel farther to raise the larger piston by the same amount as before. The same things happen if, instead of one large piston, there are several whose total area is larger than that of the piston applying the force. Once again, the liquid can't be compressed, and its volume remains the same as force is applied, so the force is transferred to each piston in the system simultaneously. This is like the situation in a hydraulic brake system. The cylinder with the piston that applies the force as the lever is moved is like the master brake cylinder. The connecting pipes are like the brake lines. And the four cylinders with pistons are like the wheel cylinders, except that in each M151 wheel cylinder there are two pistons, not just one. Keeping the principles we've just talked about firmly in mind, let's look at each of those components as they appear in the M151 drum brake system. Let's start by looking at the master brake cylinder. It's hard to see because of the way it's installed, so let's look inside the vehicle. The master brake cylinder is the heart of the hydraulic brake system. The brake pedal moves a piston inside the cylinder by means of this push rod.  Brake fluid also fills the brake lines through this outlet. They connect the master cylinder to the wheel cylinders at each wheel assembly. For a closer look at a wheel cylinder, let's go right into the brake assembly with the wheel and brake drum removed. In the M151, the wheel cylinder is located near the top of the brake assembly. Pistons inside the wheel cylinder bear against the studs of two brake shoes. These brake shoes are retained by springs, so they are fully floating and self-centering. The base of the shoes engage an adjusting screw, often called a star wheel, and are coupled to it by a returned spring that also helps pull the shoes away from contact with the drum. Other ends of the shoes fit against a hold down anchor pin at the top of the brake assembly. The brake shoes are surfaced with linings that will wear down as the brakes are used. The brake drum mounts over the brake shoes, which apply pressure to the inner surface to stop wheel rotation. Now we'll concentrate on the principles of operation of a service brake system using drum brakes like that in the M151. In this system, the brake pedal is a lever that multiplies the amount of force applied by the operator by mechanical means. But that force is multiplied further by the hydraulic system. So first, let's look at the active hydraulic components. The master cylinder and wheel cylinders to see how that happens. Then let's see how all parts operate as a system to make the drum brakes work. The master cylinder has two basic sections. One is a storage area called a reservoir for the fluid. The other section is a cylinder which contains a spool shaped piston. Small holes are drilled through one rim of this piston. The cylinder also contains two sealing cups. A return spring. And an outlet check valve called a residual pressure valve with its own spring. A push rod transfers brake pedal action to the piston. The reservoir contains a supply of brake fluid. It's important to leave some space above the brake fluid to allow for expansion. Brake fluid must not be allowed to drain out of the reservoir completely because this will let air into the brake lines and we'll see what effect that has later. Your manual will tell you what the proper level is. Keep it there at all times and you won't get yourself or the users of the vehicle in trouble. One thing more about brake fluid. It absorbs water which could cause serious problems throughout the brake system. So keep the reservoir tightly covered at all times. The two ports in the base of the reservoir provide pathways for brake fluid movement. The filler port is larger and supplies brake fluid to the system. The compensating port is smaller and allows passage of expanding or contracting fluid. Fluid movement is controlled by the action of the piston and two cups which both point forward. As the push rod transmits pedal motion the spring applies force against the residual pressure valve. While at the same time the piston cup closes the compensating port. This primary cup faces forward and as piston motion continues it seals in the pressure that now starts building up in the outlet end of the cylinder. This fluid pressure unseats the residual pressure valve opening the way for the brake fluid to pressurize the brake lines and wheel cylinders. We'll look at what happens there in a moment. For now let's follow the action in the cylinder when the brake pedal is released. The spring drives the piston and ceiling cup backward and so pressure forward of it and in the brake line drops. This brake line pressure bears against the residual pressure valve tending to hold it open. But eventually as brake line pressure decreases the spring overcomes its force and reseats the residual pressure valve. This traps a small amount of pressure in the brake lines and wheel cylinders and we'll see the effects of that later. As piston motion continues the compensating port is reopened. Brake fluid flows back into the reservoir through this path. Also the return spring pushes the piston back faster than fluid can return. This drops the pressure ahead of the cup so it is now free to flex and unseal the holes in the rim of the piston. Fluid can now return to the outlet end by this path ensuring that this space will be completely filled for the next braking action. The spring drives the piston back against its stop to complete the braking cycle. Because the secondary cup at this end of the cylinder also faces forward no brake fluid can leak out of the system. Now let's get into the other active hydraulic component the wheel cylinder and see how that operates. This device is connected to the steel brake lines by a flexible tube that allows for turning and up and down movement of the wheel. Inside are two pistons that bear on the brake shoes a spring that positions sealing cups against the pistons and a bleed air valve that lets you get rid of air in the brake system as we're showing you here on another wheel cylinder. The combined area of the wheel cylinder pistons is larger than that of the master cylinder piston. So the force that the master cylinder piston applies is multiplied several times adding to the force provided by brake pedal leverage. As the piston in the master cylinder puts pressure on the brake fluid this forces the wheel cylinder pistons to move the brake shoes apart. We've exaggerated the action here so you can see what happens. Brake shoe springs return the pistons to their stops as brake pedal pressure is released. The piston cups face inward and so prevent brake fluid from leaking out. Now we're ready to look at the entire drum brake system and see how it operates. You can control the amount of braking power the hydraulic system will deliver all the way from slowing down wheel roll to wheel lock by the amount of pressure you put on the brake pedal. Here's how it works. Remember that the brake pedal acts on the master cylinder piston the same way the lever acted on the piston in our hydraulic system demonstration a while back. The brake fluid is not compressible so the further the lever pushes the piston the further the fluid pushes the second piston. The same thing happens in the drum brake system. The result is that as pressure on the brake pedal increases so does the pressure exerted on the brake shoes by the wheel cylinder pistons. Let's look at the situation using just one drum brake assembly remembering that the same things happen at the same time at each wheel. This area is the braking surface of the drum. Actually the gap between brake shoe linings and the brake drum is very small but we're making it larger here so you can see what's going on. Let's say the wheel and the brake drum assembly attached to it is rotating. Now let's push down on the brake pedal. The master cylinder piston transmits force to the brake fluid in the brake line and in the wheel cylinder. Both pistons are forced outward against the brake shoes and these in turn are forced into contact with the brake drum. The friction between the brake shoe lining and brake drum begins to slow the wheel down slightly. Now let's push down harder on the brake pedal. Because the brake fluid can't be compressed it transmits this increased force against the wheel cylinder pistons increasing the pressure against them. The wheel cylinder pistons push harder against the brake shoes. The brake linings harder against the drum slowing the wheel even more.  Releasing the brake pedal lets the return springs pull the brake shoes back from contact with the drum and drive the pistons back to their stops in the wheel cylinder. The master cylinder piston driven back to its stop allows pressure in the system to decrease but the residual pressure valve closes keeping just enough pressure in the brake line and wheel cylinder to keep its sealing cups pressed against the pistons. These face inward so no brake fluid can escape from the system. If there is a lot of repeated braking action the friction between brake shoe linings and drums will generate excessive heat. This heat can also heat up the brake fluid in the wheel cylinder causing it to expand back up the brake lines to the master cylinder where it later returns to the reservoir through the compensating port. Now let's say some air is trapped in the brake line near a wheel cylinder like this. Air is compressible and that can cause problems. Let's again push down on the brake pedal until the brake linings make first contact with the brake drum. So far so good. But now let's push down harder. Here's where the problem shows up. The increased pressure in the brake fluid presses against the air bubble and it shrinks. Let's say the air bubble gets forced into the wheel cylinder. Plainly the full force generated by the master cylinder piston is not being transmitted to the wheel cylinder pistons and brake pedal action feels spongy. It takes a lot more pedal pressure to bring the wheel to a full stop and the air can cause uneven vehicle braking. That's why it's so important to follow directions in the manual for bleeding air from hydraulic brake systems any time you work on them. There's something else going on in a drum brake system you need to know about if you're going to really understand how this system operates overall. When drum brakes are applied, both shoes initially contact the drum with equal pressure. This is the reason why the space on each side of the anchor pin is equal. However, friction between the rotating drum and shoes tends to pull the shoes around with the drum. When this happens, one shoe is forced farther away from the anchor pin. This in turn forces the other shoe tightly against the anchor pin. This friction at this point tends to make both shoe assemblies pivot using the anchor pin as an axis. If the drum were not present to contain the shoes, the action would look like this. Since the drum is present, the shoes are forced into tighter and tighter contact with the drum. This is what is meant by the term self-energizing in reference to brake systems. This action thus multiplies the force of the brake shoes on the brake drum. One more thing you need to know about drum brake operation. You'll remember we said brake linings will wear with use. The brake pedal then has to travel farther to force the brake lining to make contact with the drum. To close this gap to normal, you'll be using an adjustment tool to rotate the star wheel on the adjustment screw. This will return brake pedal travel to normal. Excessively worn brake linings will of course have to be replaced so the shoe doesn't score the drum surface. The components and principles of operation for the drum brake system on the M151 are similar to others you might come across. And also to the drum brakes used on the rear of the M880. In part one of this program, we've reviewed the basic principles of hydraulic systems. The fact that liquid is not compressible and occupies the entire volume of its container. The fact that force applied acts in all directions. And the fact that force applied by one piston is multiplied by the areas of the others. We then reviewed the major components of a drum brake system. Master cylinder, wheel cylinders, drum brake assemblies. And talked about the principles of operation of components individually and as a system. If any of this got past you the first time around, don't feel bad, but give it another shot. Look at the program again as often as necessary to get a handle on it. In part two, we'll concentrate on the major components and principles of operation of the disc brake system used in the M880 vehicle.


Hey, this is Brett, and this 2019 Ford F350 Crew Cab Long Box Dual Rewheel is stock number 13303Z. I am here at Summit Automotive in Fond du Lac, Wisconsin, near New and used heavy-duty truck headquarters. This 2019 Ford F350 has the 6.7-liter power stroke diesel engine. This truck has been fully-safetyed and inspected by our service shop per the state of Wisconsin inspection process. It has a fresh oil and filter change. All the fluids have been checked and topped off, and this truck is 100% ready to go. I'm going to go all the way around in this video inside, underneath, start it up, and take a look under the hood. Race red is the color, and I shoot all my videos in 4K, so if you have HD capabilities on your computer, tablet, smartphone, or television, I highly recommend turning them on right now, because it is your best way to check out the quality, condition options, and cleanliness of the truck before seeing it in person as these are used trucks, and they're not all perfect.  The box and doors all look really good. Front fender is in nice shape, and if you like the video, you can subscribe to my YouTube channel, which is youtube.com. Click the bell notifications, and you'll get updates on the videos I do each and every day here at Summit Automotive. This one comes with the factory chrome step bars, the polished aluminum rims, and it has Michelin LTX AT tires. These are LT24575R17s, and they have right around half the tread left, maybe just a hair bit more on the front here. Frame and underbody is exceptionally clean, I didn't see any corrosion on there. Looks really good, and this front fender is in excellent condition as well, no dents or dings on there. Headlight lenses are nice and clear. Front bumper is in great shape. You get the chrome bumper on here, STX package, lower valance looks really good, chrome trimmed grille. This one does have the 360 cam, and the hood is in fantastic shape as well. It does have the cab lights up top. Passengers side front fender looks really nice too. Get the STX logo there, and the passenger side rim, no major scuffs or scrapes on there. Now as you go down this side of this 2019 Ford F350, take note of how clean that body is, how reflective and mirror like that paint is. I take these HD videos so if you are far away, or even if you're close by and you just cannot make the trip down but you're still interested in purchasing the vehicle, you can see the truck, hear the truck, and have confidence in the vehicle that you're looking at. Before you even get here, so when you do get here, there's absolutely no surprises and you can make a smart and informed buying decision from wherever you're at. In this video you have to make that decision, let your salesmen know that you saw the video that it was helpful and that Brett sent you. Very nice on this side, the dually tub is in really nice condition, and this back rim is in excellent shape as well. Back tires have just about as much tread as the front tires. They are worn evenly. You get the camper package with the anti-sway bar right there in that frame, and underbody is in fantastic condition as all the remaining factory exhaust, so it hasn't been altered in any way, and lower rockers and cab corners all look really nice as well. You get the factory chrome step bars, the dually tubs in excellent shape. It does have the FX4 off-road suspension package, so you get all the skid plates on there coming around at the back. The rear bumper is in great shape, does have the full towing package of course with the receiver hitch 4 pin and 7 pin wiring, and the tailgate is in very nice shape as well. You do get the tailgate step assist, locking tailgate, spray and bedliner. Really nice spray and bedliner on this one. You get the LED bed lights, which turns those on, and your cargo lights up there has the fifth wheel and gooseneck prep package. You get some tie downs, you also get a gooseneck hitch in this one, and that bed is in fantastic condition. So this is a Ford Toughbed, so it's a factory Ford liner. You can see just how nice and clean that is. The spray and bedliner goes on to the tailgate as well. You also get 7 pin wiring back here, and then side box tie downs. Tailgate shuts nice and solidly, and as we go down the rest of this side of the truck once again, dually tub looks really nice. And for full disclosure, this back room is in very nice condition as well. The cab and doors all look good. Does have the telescopic tow mirrors. They do have blind spot monitoring, built in directional signals. The telescope out like so, and fold in like that. Inside the XL package gives you the gray cloth interior. You get the 40, 20, 40 split bench seating in the front. Driver's seat is in fantastic condition. I didn't see any rips or tears on there. Get lumbar weather tech floor mats, auto headlamps, tilt, telescopic steering wheel, power windows, power locks, power mirrors. We'll take a quick look at the back seats. Back seats are just as clean as the front seats. You do get the latch child safety system in this one. The fixed glass rear window with the built in rear defrost. These seats fold up. You do get the, I believe this is the Kurt goose neck and tie down package. I came with this one. Also, you get a hazard kit there. Carpetting is nice and clean underneath these all weather floor mats. Those seats go down like so. You do get child safety locks in the back doors and the bottoms of the doors all look really good on this truck. We'll hop inside, check out the miles, the radio, and everything that this truck has to offer on the interior. You can see that this one has 23,471 miles. You do get the digital instrument cluster there. I'm going to dim it down here just a little bit. And digital speedometer, compass display, instrument clusters nice and clean. You get the multifunction steering wheel cruise controls and information center controls on the left. And Bluetooth and audio controls on the right, steering wheel is in fantastic condition. This one does have these six speed automatic transmission with the optional tap shift. This one has the sync eight inch radio. You do get AM, FM, and Sirius XM radio capabilities on here. This one has also your mobile apps, Apple CarPlay, Android Auto. This is also where your 360 camera shows up as well as your different cameras that you can check out, including the cargo cam. So you can see what's going on in the bed of the truck and as well as what's going on behind you. You can zoom in on your receiver hitch to get hooked up to your boat camper trailer the first time. So really a nice system there. Factory exhaust brake, stability control, and downhill assist control.  You do get a 12 volt power point, 110 volt, 400 watt max plug-in and dual glove boxes right there. Passenger side format and seat are in excellent condition. No rips or tears on there. And the headliner is in very nice shape as well. You do get six upfitter switches right there and map lights and we'll start it up and take a look under the hood. Right up. No check engine lights or anything like that. I would personally like to thank you for checking out the video today and hopefully from this HD video you'll have been able to verify the quality condition options and cleanliness of this truck all the way around inside and out. Under the hood we have the 6.7 liter power stroke diesel engine and engine base. Very clean, runs very smooth. Once again this truck has been fully safe and inspected by our service shop as a fresh oil and filter change. All the fluids have been checked and topped off and this truck is 100% ready to go. I did want to show you the tire and loading information sticker as well as the VIN sticker. Alright, super clean truck, really nice condition, ultra clean underneath. You can tell it was very well maintained. There's your emission sticker and this truck is 100% ready to go. I would highly recommend it from a quality and condition standpoint and to see more pictures of this truck or one of our other 550 new and used cars, trucks, SUVs, minivans, wranglers, halftones, three quarter tons, one tons. You name it we got to go to that website right there, summitauto.com. Full pictures and descriptions of every single vehicle from two locations all at summitauto.com. If you'd like to check out more HD videos you can go to youtube.com or summitauto. Remember to like, subscribe, and channel this video and all the videos that you see there. In fact, in a second you'll see a link to subscribe to my YouTube channel in the upper left. Link to more F350 videos like this one I've done in the upper right. Link to this vehicle on our website in the lower left. And a link to one of our latest YouTube videos in the lower right. With those, check us out. We're super excited to help you with this ultra clean 2019 Ford F350 Crew Cab Long Box Dually XL STX Package in race red clear coat. Thanks again for checking out the video. Remember to like, subscribe, and channel the YouTube channel. I really appreciate it. Thanks again.


Good afternoon everyone, I hope you enjoyed your afternoon tea on Australia Day. Everyone's out at the beach, swanning around there. Simon Holman is going to be giving us a talk on the network's bandwidth isolation. For those of you who've got questions, if you could raise your hand before you ask your questions so that you can get this microphone, it will be handed to you by one of our floor walkers. That will allow AV to pick up your voice so it doesn't look funny on the film. Over to you Simon. Hello everyone, thank you for sparing your time for me today. I'm going to be talking about network bandwidth isolation which basically means doing QoS in virtual hosts. As it says my name is Simon Holman, I work for my own company in Tokyo although I am actually from Sydney. So just a quick overview of what we'll be talking about today. I'm going to talk a little bit about the scope of this talk. And then I'm going to talk about how we can identify packets that are coming from guests. I'm going to talk about how we can schedule them. And then I'm going to talk about some rather interesting problems that I came up against when deploying this on Red Hat 5, which I believe people still use. So what's the aim of this? Why do I care? What are I worried about? We want to basically ensure that all of the guests receive a fair share of bandwidth. And importantly we want the definition of fair share, we want that to be configurable by the administrator. Specifically it's quite common to have different levels of service in the silver, gold, bronze kind of system. And of course if you're a gold customer you would like to get what you paid for. Specifically we're looking in an environment where the different guests have been essentially sold to different customers. They're not necessarily cooperative and even if they are they may not have upgraded their machines correctly and they may have some malicious software running there. So essentially we're talking about a stream of UDP packets which is going to cause a DOS on the machine and we'd like to mitigate that somehow. This work was all done with Zen. I'm actually doing quite a lot of work with KVM at the moment. So I do understand the KVM side of things much better than I used to but the assumptions that are made in this talk are Zen. If you try and take this and use it on KVM I can tell you with certainty that it will not work as you expect. We're talking about bridge networking. We're not routing the packets from the guests or anything like this. Everything is running Linux and I'm only talking about the transmit path. Doing QoS on ingress traffic is quite a different topic and I don't even attempt to tackle that. So what are the resources that we need to worry about? What are the resources that I considered when I was worrying about this? There are three. There's a bandwidth of the NIC itself which is I guess the obvious one. Less obvious but more important is the CPU on the host where DOM0 is what Zen people call the host and also the slightly tended to be less of a problem but the memory of DOM0. So the guest is running on the machine and it basically has limitations placed on it but when it sends packets they have to be processed by the host and that naturally consumes some resources on the host and if it's able to consume a lot of resources on the host then that may cause the host not to be able to service requests for other guests in the manner you might like. So briefly I'm just going to introduce the concept of packet scheduling. It is what it sounds like. You prioritize packets based on the domain and this allows us to basically very obviously maps directly to the bandwidth usage and also the CPU usage because CPU usage is directly proportional to the number of packets that are being processed by per second. So those kind of get grouped together. The memory usage actually relates to the number of packets that are in queue in the system in any given time which kind of relates to how fast they're going in versus how fast they're going out. But typically the queue lengths are fixed so this memory is essentially managed. So I want to talk real quickly about how flow control works in Zen and this is not how it works in KVM. So what have we got? We've got a guest over here and this net front is basically the guest driver. This is how it's sending packets and over here we have the host DOM0 and in between we have this magic ring buffer thing. So basically what happens here we have just one packet and it's got a bit of a header there which is labeled packet for some reason but it's got a fragment, just one fragment, it could be more but usually just one and some metadata and this essentially is going to consume two slots. It's pretty straightforward so far. The metadata gets processed straight away and goes straight back on the free list so that slot can be reused. So if this thing was completely full we now have one free slot which is not enough to send a new packet but half enough. The fragment itself that doesn't get freed straight away. That basically goes all the way through the network stack until eventually it gets transmitted on the physical NIC driver. And then finally once that's happened it goes back on the free list and well if nothing else has happened now we have two slots free over here we can send another packet. Obviously there are more than two slots on the ring buffer. I think the default is about 256. Fundamentally the idea is that if packets are coming in here much faster than they're going out here this will have to slow down. It can spin the CPU doing other things but that's okay because it's its own CPU. It can't send oodles and oodles of rubbish here which then has to be processed by over here. It will be slowed down and this is fundamental. This is flow control or back pressure. Without this none of what the rest of what I will speak of today would work at all. Okay so that's the background. That's sort of the foundations of where I'm coming from and the terminology of how to describe what I want to do. If we're going to do flow control on packets coming from guests we need to be able to identify them somehow to be able to say this packet came from guest zero and the packet came from guest one. So this is what a bridge network looks like in my brain. I guess you can draw this diagram differently but essentially you have several guests and the several guests are connected to a host. The host, you have basically virtual network here, which is the other half of it's here and you have several of them and then they all get bridged here and then they're sharing a single output interface. I'm primarily focused on packets that are coming out here. Of course they could also do this kind of thing. That's fine. That also fits in this model. I'm just not going to put that in my examples. So how do we identify packets? There are several ways, two of which are interesting are IP tables. IP tables can basically look at packets that are going through any interface and it can place a mark on them. Another technology which is a bit newer and I don't think it's actually particularly useful for Zen but is the net CLS and basically this is a C-group for networking so we can place tasks inside the C-group and then essentially any packet that originates for a task in a given C-group will be stamped with the mark that's also associated with that C-group. I'm not sure. I actually added that quite recently to this slide. That would work quite well in KVM because essentially you can quite readily associate a host with processes. In Zen it's not clear to me that that's possible although I haven't specifically investigated that. In any case I will be using IP tables for my examples today. So this is the same diagram again with some arrows drawn out so we're looking at packets coming out here. So basically what we can do is we look at this interface or this one and this one. We work out which interface the packet's coming from and we stamp a mark on it accordingly. This is how we identify the packets. So these are some very simple IP tables rules which achieves that. Basically what we do is for each of the three virtual interfaces 2.0, 3.0, 5.0 we give each of them an individual mark 100, 110, 120. It's not important what that number is it's just important that it's unique between the three or not. If you wanted to group them you could give two interfaces the same mark. And it's also of course important that when we use those numbers a bit later we consistently use the same numbers in the same way. Okay so that's how we identify packets. It's not particularly a challenging part. We're now going to look at how we can schedule them so how we can slow them down speed or not speed them up. Slow them down or not slow them down. So there are a couple of different things we do when we're doing packets scheduling. Firstly we have to filter the packets which essentially is the identifying part. We just have to hook into that mark that we've already set. Then we can prioritize the packets. We might choose to delay from packets and we queue them up an event or we can drop them. This is basically the kind of things we're doing when we're packet scheduling. So just going back to the memory briefly the amount of memory that a given guest is consuming for its packets in the DOM0 kernel is limited. It relates directly to the number of ring buffer slots. We basically can't have more packets in queue than there are ring buffer slots and each packet has a finite size. So that's kind of nice. In terms of the speed of the packets going through the system which relates to the CPU usage and the NIC usage, bandwidth usage delaying packets should be sufficient for our needs. If we're getting too many packets from the guest too many packets per second it seems logical to just reduce the number that we're actually processing per second and because of the flow control semantics that I described a little earlier that will slow the guest down. Dropping the packets I kind of initially thought that maybe dropping the packets might be a good idea. It's actually not a very good idea at all because of course as soon as you drop the packet as soon as the host drops a packet the ring buffer slot is freed the guest can send another one and you tend to get into a very, very fast loop of packets coming in and being dropped and then the CPU usage typically goes to around 100% and this is precisely what we're trying to avoid. Okay, so this borrowing is a slightly different topic but the idea of borrowing is essentially let's say that you have two classes set up or two guests set up and they're each allowed 200 megabytes a second but you know you've got a gigabyte, Nick and you know that absolutely nothing is happening on the system and you think maybe, okay, that's fine you can use the entire Nick if it's free and basically that's the concept of borrowing is to allow, so you have a rate which is like a guaranteed amount of bandwidth and then you have this ceiling which is you might get that as long as nothing else is going on it depends on your view of bandwidth of whether or not you, how you want to limit it but essentially if your bandwidth is free maybe it's all in the same data center this notion makes quite a lot of sense so here is the class hierarchy that I'm going to try and set up for my three guests and I'm going to have borrowing so I have each of these guests each of these circles here represents a guest so there's one for each of the three guests and there's a third one which is the default which essentially means traffic coming from the host itself we have a parent and this basically sets the global limits and this ties into the borrowing idea so essentially we have a global limit of 900 megabits a second and so if only one guest is doing anything that's the limit that's going to apply because I've set the ceiling also to be 900 in each class but if there is some contention on the network then essentially these limits will come into play so I've given one guest 500 megabits a second and the rest of them 100 each these numbers are fairly arbitrary I don't think they all add up to 900 but I think you get the idea so how do we configure this? what's command do we run? it's a TC command, the traffic control command and this is used to configure traffic control it's used to configure the filters it's used to configure the classification and it's used to configure the Q disks so firstly we do the root class which was the one right at the top of that diagram with the green circles there it is, it's an HDB class HDB is just the name of the specific algorithm I've chosen to use and then we also do the inner class which is the one just below it which essentially is a pool of bandwidth for the borrowing and here we've got rates 900 and the ceilings 900 this is actually redundant because the ceiling will default to be the rate I just put it in there to be quite explicit about what's going on and now we add the leaf classes again these numbers correspond to the diagram the first one has 900 megabits a second and the following three have 100 each all of the classes have a ceiling of 900 megabits a second and these, the parent so these numbers here, the parent number is the parent of the class on the previous slide again it's just a number that and here we name each class we give it its own name so we can refer to it a little bit later and then finally we put a Q on the end actually this is also not necessary we put there by default but again it's good to define these things explicitly I think so we have one Q disk for each of the classes on the previous slide these numbers here correspond to the handle names we gave in the previous slide these numbers are fairly arbitrary because these Q disks don't have any children and we're giving a limit of a thousand packets per Q this again is pretty arbitrary in practice I found that anything above about 16 was enough anything below that I'll discuss that a little bit more when I get to the problems I found okay so the last thing that we're going to do with TC is the filter so this is basically when the packets are coming through we have to assign them to the class and the way these filters work is we're actually hooking into the firewall mark which was set using IP tables a little earlier and that's these numbers here 100, 110, 120 you'll note that the default flow is actually being filtered because it will go there by default these handle numbers are fairly arbitrary I just chose to use the same numbers again so now essentially we've set up all of the rules as per the diagram with the green circles okay so maybe I should stop now and ask if there's any questions I'm not going to demo this I tested it extensively there's not a lot to see you push packets through and you see if they go through at the right rate if you could put your hand up when you've got a question we'll make sure a microphone comes to you I think there's a question at the back Simon you were talking about the ring buffer that's used to talk in the user domain into the DOM 0 so if the default buffer is 256 fragments because you're using the when you're using the TC filters aren't you risking adding a lot of latency you've got packets queued up before they're being transmitted I guess I'm thinking around the Gettys buffer bloat with a you know sort of idea that's a good question so the question I've recently started doing work on latency this is obviously much more directed towards throughput I don't think that actually 256 creates a big problem because the last time I checked the way that the when the kernel network in core wants to send packets it basically sends them and grabs a bunch of I think it was 100 packets from interface and sends them and then sends another 100 from the next interface and goes around in a loop like that and 256 is more or less in keeping with that because it's only actually 200 and it's only slightly over 100 packets so I wouldn't expect packets to be queued up extensively in the ring buffer but you are right I mean I'm adding more and more queues and yes I think that does have latency implications and I haven't really assessed that you mentioned early on that there's some implementation differences in terms of how the bridging works between Zen and KVM have you done something similar with KVM in terms of producing this behavior right so I have done some work on KVM quite recently so this mechanism I describe with the flow control this is the nub of the difference I've described how the Zen side works the KVM side I'm a little less familiar with but essentially what you have is the packets end up in the QMU process and then they get pushed into the kernel through a socket so you have a socket buffer which is essentially your feedback mechanism for this kind of back pressure unfortunately there appear to be some bugs in that and there is a school of thought that the socket buffer size should be reduced to zero which would mean there would be no back pressure and there would be no chance that this works at all ignoring that the current situation is unless you have a corner case in your configuration which causes your SKBs to be cloned as they go through the kernel you will get back pressure and it will work more or less as I've described here you probably want to use net classes rather than IP tables that's just details so have you been doing it with Enterprise 5.5 or have you been using so this work here was done on 5.5 my KVM work has just been using kernel.org kernels to 637 is what was current before I came on this trip especially with Red Hat Enterprise 6 and the adoption of C groups as part of the supported base there's a whole load of work in that network stack that is one area myself I haven't had a chance to play with yet it's a little bit more complicated than a few of the other C group modules that you can use it would be interesting to see how much work you can do in terms of ingress and egress packet control but that's one of the same ingress I did do actually some work on ingress and KVM recently the main problem with ingress is the policy engine can only drop packets and that doesn't then I can easily create scenarios where the CPU is spinning quite hard especially for instance if I'm doing ingress filtering and the traffic is going to another VM perhaps we should take it offline because it's actually quite a... if you want I can hook you up with one of the guys in the Red Hat BT lab that would be great but my personal opinion my personal feeling of the KVM stuff right now having worked on it for only a short time is there's been a lot of focus on performance and correctness and not so much focus on making sure the QoS side of things works properly I would like to change that I think you're going to see an awful lot of work in that area because it's the only way we can compete with VM we're in the virtualization space yes so I mean I have I go to my customers and they're mostly using Zen this is the QoS issue is very important to them but maybe we should move on to the interesting problems I found which also all have fixes so before you put your hands up and ask for the fix I will get to that so I was using Red Hat 5.4 real 5.4 I believe something like that I think these problems are all relevant because I haven't filed them in the bug track yet and I apologize for that so what's the problem here VLANs don't support ScatterGather they do now they don't in the 2618 kernel which is what Red Hat is based on what's okay so ScatterGather is basically the idea that I have a bunch of fragments that comprise a packet or an SKB I don't have to join them all up into a contiguous memory segment before doing the transmit so if they come in as multiple packets they pass through the whole multiple fragments they can pass through the whole stack as multiple fragments and the network card will magically combine them at the very last minute it's a performance optimization you want to use it regardless of the problem I'm trying to describe if you have a nick that doesn't support ScatterGather which is essentially no nicks just happens that VLAN is a corner case that hadn't been fixed yet it will linearize them so it basically makes a copy of the SKB and copies all the data from the different fragments into one big fragment this completely destroys the flow control I described in that diagram which had lots of arrows on it which means that the ring buffer slots become freed a lot earlier than they should be and so the CPU basically will just get into a feedback loop of the guests send something and the host drops it the results are quite profound you essentially lose any kind of interactivity to the host it's a problem so to work around if you're worried about this, this will work on essentially any version of Zen on any kernel is to rate limit the virtual nick itself actually has a rate limiting facility and this is how you activate it this still uses quite a bit of CPU because there's dropping going on but it just turns out that it drops them early enough that the DOS kind of scenario doesn't manifest the solution to this problem is to enable scatter gather on VLAN and that has been done in newer kernels at least but the problem would still manifest if you happen to find another interface whether it be physical or virtual that didn't support scatter gather so there's a general problem there I kind of doubt that anyone's actually running into it other than the VLAN case so here's some details of the patches that fix it up they're actually quite short problem solved okay, problem two there are only three problems so I'm getting towards the end anyway bonding we observed a different problem when we were using bonding interfaces essentially what we would try to do is set some classes up to use around about half a gigabit a second and we'd be getting sort of about 10% of that not really what we wanted not as bad as the DOS problem but it's still not real good so some solutions to this problem which are well, sorry, I'll go back so why is this a problem how does this problem how does it happen basically what happens is by default the bonding interface which is a virtual interface of sorts has a Q length of zero and the bonding interface is always going to be backed by some physical interface it has its own Q why add another Q okay, that's fine when you add a Q disk to any interface its default Q length will be that of the interface it's been connected to okay, so we end up with a Q disk of with a Q length of zero and essentially the way that the HTB algorithm works and I can't explain exactly why this is the case but the way that it works is it actually needs a little bit of buffer if it can only has one packet to play with it can't actually do its job effectively and that's the result that you're seeing at the bottom of this slide fortunately this problem is trivial to fix I did actually ask the the bonding maintainer whether this behavior was intentional and he said yes so I didn't, there's no patches but all you have to do is increase the Q length um a thousand seems to be the magic number that everyone uses I actually found that anything from about 16 was okay uh, so problem solved works all as expected okay, the third and last problem sorry oh, Herbert so yeah, back on that bonding issue wouldn't another possible solution be to actually apply your rating on the physical interfaces rather than the bonding interface itself could I apply the rate limiting on the physical interface rather than bonding interface? probably yes and that might actually be more logical yeah uh, yeah, actually and in this case the bond was um they were doing it for high availability rather than aggregation so that would work just fine, I expect okay, so maybe this was a poor design problem okay, so the last one is is a bug which has been fixed um so TSO is a mechanism by which essentially SKBs that are much larger than packet SKBs that are much larger than MTU length traverse the network stack until right at the last minute when they're diced up or segmented into MTU size bytes and the reason is it's much easier to it's much cheaper to process one very large packet than many small packets okay, that's fine, unfortunately there's a problem with this in relation to the way that HDB accounts for the cost of a packet um, and it's really geared towards the idea that basically everyone's using 1500 byte packets whereas in the TSO case um you can quite easily see 64,000 64 64 kilobyte packets coming in from the guest so it's significantly larger than 1500 bytes um, and the result is essentially that you might be missed it's basically the same as if you don't have any of this configuration I spoke of earlier said at all um, so it's a bit of a problem so I'll try and explain very briefly uh, why this occurs um, essentially we create, we the code calculates this value called um, CL log, which is related to the log 2 of the MTU where the MTU for some reason I don't understand is 2047 which is a number close to 1500 but never mind, it doesn't matter um, that's actually unimportant to this problem the point is that this is quite a long way from 64,000 um and the answer to this is 3, I actually modified this code um, this slide's not about the math, it's about the fact that it's a log based on some number around 2000 um, and we get 3, and then what do we do we basically set up a table based on this, and this table is gonna basically tell us for each of a range of packet sizes how much they cost they should be charged and the table looks a little bit like this is little tiny packets like this um get a value of 16 oh sorry get a value of 16, yeah, and packets up to about this size get a value around 2000 and this is the critical one any packet that's bigger than this gets a value of this ok, that's not so bad but this means that a 2 kilobyte packet will be accounted as 2000, but a 64 kilobyte packet will also be accounted as 2000, so that's not good, it's being under charged by quite a margin um so, I should have mentioned earlier, I was not allowed to modify the production kernel at all so this is why there's these workarounds um, the workaround number one which doesn't really work is to turn off TSO and the guest that's ok, except I said earlier on my guests were not necessarily very friendly so they could just turn it back on it ok, it's a problem I guess yeah, I guess I could have refused it somehow, but I'm not sure look at round number two is much more effective we changed that magic 2000 value to another magic number which is 40,000 um, we observed that 40,000 is also knocked 64,000 but it is much closer and it turns out to that in terms of the way that table I showed earlier works that that is a good number it's big enough to account it's big enough that the really big packets get charged sufficiently highly and that we don't lose too much granularity at the lower end and this basically works ok, so if you have this problem this is what I would suggest doing the solution to the problem however is to of course fix the kernel so all it does is basically says ok, you're 64,000 byte packet, ok so that's like 32,000 byte packet so we'll just charge you 32 times the maximum rate plus any change that's left over at the end and that works basically the algorithm now works as it was intended so this is the end of my presentation today so what did I get out of this process existing infrastructure works quite well for doing bandwidth control I expected to do a lot more development than I did I mean other than these bug fixes I did none, which was disappointing because I'm a developer you know so the key you need to do is you need to be able to identify the packets the example I gave was extremely simple where we're just trying to basically break it down on a per guest basis you may quite easily want to do something more complicated, in fact in the scenario that this is going into the host was actually using iSCSI and so we wanted to ensure that it got a fair amount of bandwidth and so it had its own class the fact that HTB is hierarchical made that possible yes, so you need to identify what the problem is and design appropriate class hierarchy and perhaps the most important thing is there are subtle traps this TC in particular, but in general Linux networking is very complicated, there are many many knobs you may think that you've turned the ones to do what you want to do you need to test, I'm pretty sure that there are holes in the rules that I wrote above, but they passed the tests for the traffic that we were interested in and I'm not sure there's much more you can do than that thank you everybody for your time and I think we have time for more questions so is there actually anything specific to a virtualized environment here I mean it seems to me that you'd have exactly the same problem with a bunch of real physically different hosts behind a switch as long as the things on one side of the switch have a greater aggregate bandwidth than what's on the outside which would almost always be the case I would think yes, so this is a many of these problems are generic at many levels so yes if you looked at a physical network you would see similar problems even actually if you looked at processes from forget virtualization you can create similar scenarios so it's a very specific work look at a very general problem all right well Simon thank you very much indeed well thank you


Hey guys, it's Nate, aka The Foot Accountant. Welcome back to the channel. Happy Monday, first Monday of the New Year, of course, and today we're asking the question, with the New Year starting, is EA going to continue their trend of upgrade packs on Mondays? Now, I'm not just talking about the simple 80 plus upgrade or the 75 plus player pick like we had last week during Winter Wild Cards Team 1, I'm talking about these sorts of packs. The base icon player pick that we had yesterday is kind of thrown us for a little bit of a loop because usually these sorts of gamble pack SBCs, the fun upgrade pack SBCs like these, drop on Mondays as well. So the fact that this is already out, what's that going to mean for today? But I want to talk about this SBC, how it's impacting the market and what that could mean for the market today as well. And the content today on Monday, as Mondays are usually pretty exciting days for content, also pretty exciting days for the market as a lot of people see and expect the market to rise on Mondays as people get weakened league rewards and of course go out and build some teams. But of course, with all the objectives that are available right now, a lot of the grind is in draft or maybe in friendly modes where you don't need your most meta team, will that deter people from going out and buying some promo cards or buying some cards off the market to better their squad after they get rewards? We'll talk about that and kind of the gameplay demand on the game this week, especially today on Monday, which is normally a day where we do see a market rise. But with all things considered, could the market rise be a little less because of that? So we're going to talk about a lot in today's video. So if you're excited for it, hit the thumbs up and subscribe if you're new. Let's start by just the Monday normal, right? The Monday normal is the regular upgrade pack, which you guys know the drill. Last week we had a 75 plus player pick, right? And these are just the fun, repeatable SBCs that we do to try to pack promo cards. So maybe today they'll mix it up and give us like a double player pack. I really liked those 80 plus doubles that came out a couple of weeks ago, but the best thing you can do to get your club ready for those SBCs today would just be if you want to do those SBCs, by the way, definitely not like a huge incredible investment opportunity. I don't think these non rares or rares would move too much more than a couple hundred coins a piece, but stocking your club with non rares at 350 coins or gold rares at 600 650 coins is a very easy way to get those SBCs done for cheaper throughout this week or just today in general. Of course, that's the usual Monday upgrade pack SBC that we will see. I do expect those today, but the real question is what's EA going to do because they dropped the base icon player pick yesterday on Saturday. And I mean, it's a decent value SBC. It's not terrible, but again, all I think of right now is yes, there's a lot of fodder. There's going to be a lot more fodder we're able to get this week. A lot of people are going to do this SBC just because it's there and it's fun and it's a gamble. I mean, look at this 74% upboats for a 100,050 coin base icon player pick. I don't like this SBC because it's the base icon, right? I think it's a gamble. I've seen a lot of people do this and not get very good stuff. Of course, you could get some really, really great players like the Jarzinio base version, you could get Prushkash, Ronaldinho, Eto, Mateus, right? You could get some really, really good players from this, but you could also get some really, really not so good players and with how cheap the base icons are in this stage of the game, like even Beckham's 150k. I mean, the value on this SBC is not bad at 150k because there's a lot of base icons that are still at 150k or above, but also I think a lot of people are disappointed with the outcome of this SBC. I would much more rather start working on a player SBC like Belagarde or if I have not done Eric Bayi or Celas or just send that fodder into the Jarzinio or the Maldini icon SBCs. That's where I'm going to be putting my focus instead of this base icon player pick, but I'm not going to say it's a terrible decision if you want to go for the gamble because 150k, two squads, 85-86 is not that bad. So speaking of that SBC being yesterday though, we'll talk about how that impacted the market here in just a second, but the trend is that usually these come out on Mondays, right? So this reminds me of just a couple of weeks ago in this game, we had the same situation happen. Maybe you guys might remember the 88 plus mid or FIFA World Cup icon upgrade, which personally I would rather have this again than to have this one because mid or World Cup icons, that's, you know, better icons than base icons. But anyways, that's besides the point. This dropped on a Sunday and what followed the Monday after the day after was just upgrade packs and it may be like the 85 plus double or something like really, really small. Could that be what happens today on this game? I think that's my favorite idea of what content might be today because when EA dropped these big icon upgrades or just big gamble packs in general on Sundays, usually the day after that on Monday is just kind of a simple day where they do drop an upgrade pack SBC for like, you know, just the gold upgrade like 75 plus or the 81 plus, but then they don't do too much else other than that. Of course, one addition to that argument right now is EA just dropped even more stuff and objectives, right? They really want us to be focusing on gameplay right now to get the swap tokens in the first owner fiesta in the Winter Wild Cards Cup in the draft, right? With footchamps stuff, they want us to play games to get these tokens here. They're trying to get us to do these gameplay objectives and that's where a lot of their focus has been put with the content. So that almost makes me think that the content this week might be a little bit slower and that could be why today we maybe don't have another sort of gamble pack SBC, especially because we had this yesterday. So that's kind of what's in my mind. I think that is like my favorite and top, I guess, idea of what might be coming today. Of course, we all know that EA could have an idea of their own and they could do something crazy. I mean, guys, we have an 86 plus hero upgrade that was released last week that technically expires today, right? This, this SBC is expiring today. Could EA refresh it and drop an icon upgrade yesterday and then a hero upgrade again today? Who says they can't, right? They could absolutely go ahead and do that. So it's just going to depend on what the content is from EA to see what the market moves like today. But the reason why I'm saying that I don't think the content is going to be that spectacular today or just to watch out for it is if it isn't our normal Monday market rise should see an additional rise after content today if the content is slow. Like by slow, I mean, even if we get like an 85 plus double, right? An 85 plus double pack like they dropped last week, early in the week would be a very, very possible SBC that we see today. That to me is not an expensive enough of an SBC or a hype enough of an SBC to make the market move that much apart from maybe like your 83s and your 84s going up a little bit. So I'm not expecting content today to be that crazy. Now, could it, it still could be good, but I don't think it's going to be that nuts, which makes me think the market could rise even further after content today. It's all into EA's hands. So kind of just take this information with what it is. And if you're trying to flip some cards today like I am, you know, maybe if you see some really good prices before the 6pm content drop today, maybe you look to sell some cards. But if you think that some of these cards could potentially go higher, then it is what it is. I've got a whole bunch of cards in my transfer list. I'm like three and a half million vested at the moment, just trying to work some stuff out and try to make some coins, because the market does seem very healthy. But I do believe that it could be one of the last like solid market rises before we start to see maybe some downturn later on this week. And again, what's really going to make the market start to turn down later in this week and into this next weekend. And as we get closer and closer to the team of the year is the leaks, if people start deciding to panic sell and whatever is going to cause that panic selling, whether it's insane, insane content or leaks. I mean, I think we are due panic selling really, really soon. Again, I talked about it on the weekend. Prices are still pretty stable. We're still seeing a very healthy market. But I think we are getting to that window where the market's gone up now for like a week and a half, two weeks, and we're getting really close to the team of the year. It's time really close again where the market is going to start to get panic sold. And a lot of prices are going to drop off. So that's just kind of looming, right? But maybe it's not here just yet. Now, I want to talk about this icon player pick a little bit because you might be like, Nate, fodder went up a little bit yesterday because of this, but like it didn't go up like crazy. What if you're invested in fodder right now? What should you do? What should I do with fodder in my club? Well, this is why fodder didn't go up that much because also yesterday, we had a New Year's cheer, SBC, which is I believe where our token was. And it was a solid pack as well. If I can find the SBC New Year's kickoff, that's where it was. So they dropped a token in this and a tradable mega pack, really, really good value SBC. It's like 3,000 coins to do for a tradable mega pack. That's a lot of supply for the market. You know where you can actually see this take place and really in action. If you take a look at the index 100 on foot bin, you can see this right content yesterday, the market rose for just a tiny bit, right? As a lot of your 83s and your 84s, they jumped up in price right away with that, that icon player pick being out and the Bella Garda SBC bearing very cheap and requiring some low rated golds. You can see 83s boom, they went up a little bit, but now they're kind of back down. Same thing with 84s, right? The index 84 was low, it boomed, but that supply from that mega pack and the tradable packs that you get from doing the base icon player pick kept supplying the market and Bella Garda is two different SBCs as well. So there's a decent amount of tradable supply that hit the market yesterday. And that's what I think kept as kept these fodder prices going down. And the market in general stuff that was in packs yesterday. I even think of like some of your basic gold cards. Now Van Dyke is maybe not the best example because the best of, the winter best of that we're talking about over the weekend finally was released from packs. It's no longer in packs. And guys like Van Dyke and Gold Ronaldo went down a decent amount. And but now they're back up a little bit, right? Because we had a lot of panic selling and a lot of supplies since they were released back into packs as their special versions went out of packs. I think like Vinny Jr. was like 25,000 coins, I believe, and he went all the way down to like 20k. So that's that's a pretty sizable drop for that cheap of a card, right? 24,000 coins down to 18k. Now he's back up to about 20 to 21. So, you know, we had a really, really low point on the market with the combination of supply from the mega pack and from all the packs being open from the icon player pick segments and from the Bella Garda SBC segments. And you had panic selling on top of that for people that were selling cards to go and do the base icon player pick. But since we had all that supply, it didn't really move the fodder market. If you have fodder, you might as well just hold, right? Because think about it still, we're getting daily player SBCs. And the only thing you have to be kind of, you know, knowing is coming out in this game this week with fodder is we're getting the big time FIFA World Cup rewards. And we're going to talk about this more throughout the rest of the week this week. Do I believe that these rewards are going to crash fodder? No, not at all, because these are untradable. What this is going to do is give people duplicates as they open the packs from this, or as they even I believe yesterday, which I'm going to open mine on this video, everybody got 81 times 11 packs, or people are getting these from doing the completion objectives for the daily login. We're going to get an 83 times 10 on Tuesday after we complete the 12th and final Winter Wild Card daily login SBC. That's going to be a lot of fodder. I think that helps people go out and do SBCs because it's all untradable. And I do believe you will see some parts of the SBC market continue to go up specifically on the top tier, because especially if you're doing Jarzinio, and you're packing a bunch of like 83s, 84s and 85s, maybe a couple 86s, what are you going to have to go and buy? You're going to have to go and buy the 89s, the 90s and the 91s. And these guys went down a little bit yesterday. I think they were even like 55k, 53k for De Bruyne yesterday, if you bought any of this high rated fodder in this dip with all the supply, that was a fantastic, fantastic buy, because these cards are probably just going to slowly trickle up throughout the week as people are doing the Jarzinio, they're doing the Maldini SBC. Those are SBCs that people are probably going to start to do this week, because there is a lot of fodder being given out. People are also of course going to be doing the base icon player pick, and these lower tier player SBCs, and that's why I do think EA could put out like an 85 double today, and that's even an argument for EA putting out more upgrade pack SBCs this week, just because there's going to be so much fodder there that people are going to be getting, and EA of course are going to want to give people opportunities to turn that into different SBCs. So it's going to be a very interesting week because there's so much fodder available, and there's going to be so much of an emphasis around SBCs crafting, and getting stuff done, and just feeling like you have a lot of cards. It's going to feel like we probably have cards in our unassigned all week because of the reward packs, objective packs, and of course those Qatar, the World Cup red player packs that we have all collected. So I'm going to open these really fast, my 81 times 11 really quick as well, and let's start talking about the Marcula bit too. I know I mentioned it a little bit in this video, but with the demand being for like draft and with the objectives and the friendly modes, maybe there won't be as much of a demand on the market.  We get Modric Brozovic. All right, I can't complain. At least got to walk out of my 81 times 11. Will the market 286s? Let's go. All right, only 181. All right, that's I okay EA. Thank you. Appreciate it. Look, I have a duplicate. What do I have to go do? I don't want to quick sell that. I can go put that into a like draft token upgrade for 82 rated squad W's, you know what I'm saying? So that by the way, no man left behind. Like if you have duplicates like this, don't just quick sell them with so much fodder that is out. Don't quick sell that stuff this week because there is so much that you can do and craft and go and get, especially if EA drop player picks. That would be so much. Yeah, that's just incredible amounts of fodder and so much, you know, so easy to grind and craft. Don't quick sell stuff. Just rinse it back into those cheap SBCs and just work on stuff throughout the week because you'll get a lot of stuff done. But will the market be hurt at all this week because of these objectives? And personally, I think that may happen a little bit, but I still think that especially I like the lower tier side of the market and just everything that people are going to be building teams around right now. There's just a lot of gameplay demand in general people that played weak only you're getting the rewards and they might have gotten some cool cards and player picks and some good packs. And now they're motivated to continue playing the game and they're having fun on FIFA right now. So they're going to go and build teams. That's why I'm still pretty optimistic about a market rise today. I mean, I better be pretty optimistic if I spend over three and a half million coins buying cards on bid and snipes. And, you know, I'm looking at this informed Marquinhos because he is up a little bit after the players that we got yesterday in the mini release. I'm trying to stick with what is hype guys. I'm trying to stick with what is hype. And that is league one, the league one links that are where people are building their teams right now. I noticed this Akimi on bid. I thought it was a pretty cheap price in the low 400. So I went for that. I picked up a couple of Pepe's from the mini release right around. I think it was like 55,000 coins. He's, you know, slowly rising a little bit. And I'm going to try to keep an eye on some of these other cards in the game. But I'm really focusing on what is hype and that is the league one links on this market. So again, what I said in the beginning of the video is still holding through those some of these cards I might not sell before content today. A lot of times when we do our quick flips and we see a bit of a market rise on a Monday, we end up selling those cards around the content time or even before because usually afterwards we see a dip in price. But you know, today that may not be the case if the content is not going to be that great. And some of these winter wild cards, we have to talk about this, this as well. Winter wild cards team two, if you go back a week ago to right now and look at looked at the winter wild cards team one, the Monday, Sunday, Monday, Tuesday time was a really, really low point. And honestly, like the low point for a lot of these cards, Conte's 950. What was he last Monday and Tuesday, 820, 814. And he just kept rising throughout the rest of the week. A lot of the player SBCs that we have coming, they don't look that insane. We have Han, we have the Kenny right back from the Bundesliga. And then I believe we have Fadiga. Like I think these are the only player SBCs that we have leaked right now. And that's one, two, three players that would take us at least through part of the week this week. Maybe there's a couple more out there. Of course, we probably have a few more to be leaked. Maybe a surprise like the whole SBC was, but the leaked SBCs for the players at least, the daily player SBCs, don't look that amazing, right? So that to me could mean that the market could rise pretty well. And maybe some of these winter wild cards from team two, are low ish still today. But then as we head throughout the rest of the week today, or this week, just continue to rise unless we have some sort of panic situation and scenario or EA drop some absolutely insane nutty content that makes people sell cards to go get whatever content that is done, like a gamble pack, a player pick, or again, a loading screen or some leaks. So, you know, it's just, it's a big question mark right now with this market. And I'm trying to stay, you know, I'm trying to stay pretty liquid apart from just being able to do some quick safe, quick flips. I keep searching this Kimmich card, right? Because 580, he was like 660 last night. He's a really rare card. Do I think this is still overpriced for Kimmich? Absolutely. I think that, you know, in two, three weeks time, this guy's probably going to be under 500,000 coins, just because he doesn't have any pace. And with team of the year on the horizon, I think he's going to end up dropping off in price a lot. I do feel like that still some of the winter wild cards from team one are a bit overpriced, like even Joao Felix and Usman Dembele, that stuff that I would be careful with. But I think the time frame that we're in the market that we're in right now is still pretty safe. And I think it will be a good opportunity to just quick flip cards in the next couple of days, if that's the way that you like to trade. But if you're like holding on to cards in your team, because, you know, you're just wanting to see them rise in price and you think the market's going to keep going up, I think those days are numbered. So that's, you know, why I keep talking in these like different dynamics, right? In the short term, I feel like the market is healthy. But in the next two weeks, we got to be really, really careful with cards that we own. Now a quick check and a quick update on the tokens, and I want to make this video too long, of course, but we are up to 22 tokens. Yesterday they dropped it in the New Year's Kickoff SBC. A couple tokens are expiring today on the 2nd of January, of course. So make sure you check this token tracker. I'll drop the link this down below in the description if you don't know where this website is. And it tells you when the tokens expire and where they are in the game, whether it's an SBC or an objective. So make sure you go ahead and check those out there. We are on token number 22. So that means we are only guaranteed three more tokens in objectives, in SBCs, and the like. And if there's going to be any more tokens, they would be through the store, which we're running out of time on store token packs. EA's only dropped one through the moment store and one, I believe, via the, was like a 75,000 coin pack. So we're EA, you got to fix up if you're going to drop drop with some bonus tokens. I don't believe we're getting all 30, especially with only five days left, I believe. Is that it? Is there only five days left of this or four days left of the swaps program? The World Cup Swaps go away in two days. And let me check these really fast. It's getting down to crunch time, guys. It really is. Let's see how much how many time this World Cup Swaps just so long. So these are still here for 11 days. But I'm pretty sure that the tokens are going to stop on the 6th of January. I'm pretty sure that EA tweeted that out. So these are still out for 11 days, which is nice. You have time to decide on what you want to do. I'm going to be putting my remaining tokens into the 83 times 25, getting that done, and hopefully getting some fodder to be able to craft Jarzinio. I'm going to start on my Jarzinio grind this week, because it's just, it's that time, right? I think I might do Payette still, maybe DePaul, probably not. And then maybe I'll do a couple other lower tier SBCs, the cheap ones that have been dropped this week as well. But for me right now, this is just going to be an incredible week to grind, guys. Again, I said in yesterday's video, this is such top tier content from EA. There is so much to do this week. Enjoy it, right? Enjoy it with all the objective gameplay that is there, with all the packs you can earn, working up towards the Winter Wild Cards player packs, whether it's in the cup, whether it's in the daily login, or whether it's just the good packs that are in the draft objectives as well, like working up towards this stuff. Just enjoy this week, because really it's not going to get that much better than what we have right now in this game. So it's going to be a very interesting Monday. I'm excited to break it down with you guys and to just react and to watch it all unfold live on stream today. If you're tuning in to content, tune in to twitch.tv slash the foot account, link down below in the description. We'll be live streaming there at the content drop in a little before and after to kind of see what EA does. And maybe there'll be some leaks today. Maybe EA will surprise us a little bit. I don't know. But I do know we're probably getting upgrade packs. Maybe some other extra upgrade pack goodness. I want an 85 plus double back, because those were good.  People will be happy for that, for that investment. And also, those packs just seemed to be pretty decent on this game. So that's the video for today, guys. If you did enjoy, smash a thumbs up, comment down below if you have any questions and subscribe. If you are new, it's been an eighth foot account, and I'll catch you guys later. Peace out.