We may do it a bit fast, but let's try to finish that. Okay, great. So, you remember the last class? This is the goal. We were talking about larger planets, planets, diagrams and so on. Okay, so I'll give you back the rule. The rule was that the leading order in large end, the theory without fundamental matter, the only adjoints, receives contributions only from playground diagrams, genus G diagrams. More precisely, the rule was that graphs of genus G awaited by relative factor 1 over n to the power 2g. Okay, and the second rule was that an index, every hole, every index, fundamental index loop, was awaited by a factor of 1 over n, rather than 1 over n squared. Okay, so adding extra handles to the surface, or adding extra holes to the surface are both sub-dominant in the 1 over n expansion. Okay, now, of course, the whole 1 over n expansion is very interesting, but to be able to have any chance of doing that, you have to be able to solve a theory of leading order in the large end. We had many examples of theory of leading solving a theory of leading order in the large end, matrix integral, matrix quantum mechanics. But now we're in 1 plus 1 dimensions, and we want to know whether we can get a non-trivial theory of theory, and solve it in the large end limit. This problem was addressed by Doge. You know, Doge is a great theoretical system. Doge went through a fantastically creative period between 1970 and 1984, each opening 30 papers, but just individually outside of me. Each paper, you know, you wrote a problem to it. And, but in the 13th one. So, okay. So, you may have heard of the main loop of renormalization that they created. Many, many things that, and this little paper is a little gem. It's a kind of paper you could write in three days if you are there. As you can see, there's nothing to it today. So, it's so nice. Okay, so what I thought, was to study the problem. Okay? Study the model of cyber, slash, side, trace, okay? Okay? So, what's this model? The model is a model of fermions. Okay? Okay. Now, he allowed for these fermions to have a certain number of limits. Okay? So, first of these fermions were in the fundamental, in the fundamental, in the fundamental, in the fundamental representation. We generalized adding flavors a little later, but now, there's only one. Okay? So, the question about this model is, what is it? Physics. Now, suppose you were to treat this in free-field theory. In free-field theory, what would the answer be? Meaning, you know, keeping this action truncated to quadratic. Okay? So, at quadratic level, you would get you would get the quadratic part of the algorithm. But the quadratic part of the algorithm, of the algorithm itself, as we have seen before, has no degrees of right. Right? We argue this in one of the dimensions. The gauge field has no degrees of right. Okay? In general, we saw that in d-dimensions, d-2 is propagated. So, it's a freedom. So, at quadratic level, you would say that there's no propagated degrees of freedom. But, if you looked at this, you would just get free fermions. And free fermions have fermions in them. So, you would think that there would be one or an A-dependent if you got it. A-dependent, if you got it. And for me, I think it is a freedom. If you were going to do free fermions, you would get the spectrum of the theory. It would be a Hilbert space made up of a Fox space of any fermions. And then perhaps corrected to something. This is totally the wrong answer. Actually, that is the wrong answer we can see quite intuitively that there's still four dimensions but it's harder to see this intuitively, classically. But we'll come to that later. But now what we want to do is to just work in the large area. And try to see if we can just solve this theory without any intuition. It's just mathematics itself. And try to get in the spectrum. Okay? So, how are we doing this? So, first thing that both of us are analyzing this this model is to set a gauge. First, I'm going to define the location. So we're going to do two dimensions. We've got two coordinates. So let's say the dimension is a diamond space. Okay?  Yes. This whole thing is a problem. This D slash is D plus X squared. So this is what makes it an interactive thing. There are interactions between as you say it's a question. Okay? Now, we work in like-on coordinates. So X plus minus is X plus minus D. And with the lower X so suppose we take the momentum for instance, plus minus that is equal to right, is equal to let me switch to this dimension. So he calls this X. What I call the X is called X1. What I call D is called X0. Okay? X plus X1 plus nothing. But the P plus minus is equal to minus P0. Where P0, P lower 0 is minus of P upper 0. The metric this is plus minus so is this but this P0 is lower important. Which makes if you write in terms of P upper 0 to be P1, P upper 1 minus plus B. The H field in the class is equal to A1 plus minus A0. And now the point is this. What we didn't do is to try to solve the path integral of the theory. Now the theory, we're working in a particular gauge. And the gauge that we chose for this problem was the gauge A plus and A minus A minus equals A plus the path integral of the gauge theory. We made sense of the path integral. At least maybe we needed to insert an delta function. That fixed gauge. But associated with that delta function was a path integral. And the determinant when C bar times C times what A meant here was the transformation. The thing that you said to 0 is A minus. So we need to know how A minus transforms. This C So the general rule was that we got some condition. That condition is a matrix condition. Under a gauge transformation it transforms in some way involving some gauge transformation. The general rule was that the path integral of the determinant of this expression multiplied by C bar and replace lambda times the determinant of this. So how does A minus change under a gauge transformation? So the change in A minus is L minus lambda plus I minus the change in a gauge transformation. The covariate variable of the gauge transformation parameter. Okay. Do you remember this is happening when we have inserted a path integral of delta of A minus? So A minus in particular is 0. Okay. You do your path integral along with the delta function. It tells you that A minus is C. Do you remember the gauge? Yes. And therefore the full path integral of the determinant is just C bar delta minus C or the determinant of the operator D minus. Now the important point for this path integral of the determinant is that it does not involve angular side. It does not involve the gauge fields or the fermionic fields at all. Is this specific or is this gauge for this gauge? I will contrast this to what I have to learn. I will do that in a moment. But because it does not involve angular or the fermions at all, the path integral over C just gives you some overrun number. Does not affect any computation or correlation functions anything like that. And if we are interested in the path integral up to an undefined normalization, we can just forget it. So this is one of the great things about this gauge or any such gauge. Any gauge in which you set is particularly important to me. There are no ghosts in that gauge. Now what? You want to make life as simple as you can.  It looks like a lot of notches. But let me read what your question is. You can ask the question, why is this a particularly useful thing? As you might know, this gauge is rarely used in analysis of four-dimensional equations. However, this gauge is extremely useful in analysis of four-dimensional equations. And you can ask why? And that is for the following reason.   Now in two dimensions, there are only two possible mu's and mu's. If you set one of them to zero, the commutative term vanishes. And therefore, the f mu nu squared, the self-interaction of the gauge becomes effectively quadratic. This would not be true with any other gauge. Because if you have, let's say, three a's, you set one of them to zero, you can still get the commutative of the other two. So doing this is extremely advantageous in this dimension. Now you can ask, everything I said, both the lack of funny-poke as well as the kidding of self-interactions would have been true of, let's say, a zero is equal to zero for a one equal to zero. You can ask, why do I choose the set lack of future? This is because it retains boosting variance. That is, as you know, under a bool, under a bool, a minus, let's say, transforms to minus, that's right. Are you familiar with this? I'm saying something more, let's do it. Let's recall the Lorentz transformations. The Lorentz transformations are x zero prime, which is particularly significant. x zero prime is equal to cos theta x zero plus sin h beta and x one prime is equal to cos beta x one plus sin h beta x zero. You know this notation. Beta is 10 meters. You're familiar with this, right? Yeah. But it doesn't matter. Now, let's see what this means for x zero plus x one for x zero plus x one prime. How does that work? Well, we will get x zero is equal to x zero plus x one into x zero plus x x zero into cos theta plus sin h plus x one So then, 0 plus 1 into cos plus sin h. What is cos plus sin h? What is x? Simply, if you have x zero minus x one prime is equal to x zero minus x one So, the great thing about these light comb coordinates components is that they transform homogenous families. If you work in 0 and 1, you get a mixture of 0 and 1. If you work in the light comb coordinates, you just rescale the light comb. X plus stretches out and X minus stretches in. So, the light transformation as after any object in the same way with similar structure. So, this is true for X 0 and X plus and X minus such a true for X plus and X minus. And therefore, this gauge A minus equal to 0 is boosted by A. So, A minus equal to 0 in 1 light strain. That is equivalent to setting A minus equal to 0 in any other light strain. So, you retain more of the symmetries of the problem by doing this, than you would by setting A 0, A 1 to 0, which is always in the day, about the distance. One good reason actually that I have stressed something please in front of the couple. Doesn't matter. Now, if you caution you about not being careful. And the caution is that look, we have not been very careful about equipment because setting A minus equal to 0 does not completely fix gauge. It does not fix those gauge transformations that are functions only of X plus. Because under the gauge transformation, A minus changes at A minus or something. At A minus, any function of X plus is same function of only X plus. Therefore, any gauge transformations function only of X plus. It is not fixed by this gauge. This is the residue of gauge transformations. And if you try to fix that residue of gauge transformations, light will get quite complicated. Now, how? You see, doing complicated problems in physics is basically not. So, the thought has a good taste to ignore the problem. Just proceed and see what you are capable of. After 500, this way goes inside it may be a problem. People have already filled in the details. Don't work just to buy everything is done. We are going to follow it. Forget this. Forget this unfinished gauge intelligence. Small thing. Usually, if ignoring something matters, you will see it in your condition. You will see an inheritance. And you will see we run into some assumptions. So, what we are going to do is we follow just those solution paper, not try to worry too much outside of this. Follow our nose and see where we are going.  If the unfinished gauge intelligence is really bad by the way, it would show itself in the propagator not being important. It is that with main problem of the gauge intelligence. Main problem of the gauge intelligence. So, unless we run into problems with the inertiality, non-invertiality of the propagator. Okay? We gauge of not worry about things too much. It is a hit and miss approach that can sometimes hit you badly. If it works, it works very well. Okay? Fine. By the way, we do the same thing in the range gauge. We ignore unfinished gauge and variance, at least in the gradient space. Usually, quantum field queries are so complicated that they have to think through a very last subtlety and try to solve a quantum field. It is a realistic and unfeasible task. What is feasible may be put on the machine. And, you know, that is part one of the truth. This is not an addition. You proceed. It makes sense. Okay. Okay. So, you know, in that spirit, we fix this gauge intelligence. Now, once we fix this gauge, as we said, there are no self-interactions in the range gauge. Okay? Um, there are... Has it ever become purely non-interactive? No. It is what you said. There is a side bar, side e. Interactions. So, there are interactions. But, the theory is much simplified. Diagrammatic. So, we make all the diagrams this multitude. Okay? So, let's try to imagine a particular result. The example that we look at was not quite observable. The thing that we will try to compute in this case, to start with, is the propagator of the effort being fixed. Okay? Now, see, in an arbitrary gauge, what kind of a diagram should come up? All right. We will continue. We should be worried only about plane and radius. Okay? We don't want the gauge to be still. Don't talk to me like that. Now, an arbitrary gauge is what we could have planned for all categories. We could, for instance, have worked with this. Where there is a new fermion group. We could have worked with graph numbers. We are very interested in leading order and target. We are not going to allow new index groups. The feminine main index groups. Because there is a press button. Okay? So, we are not going to allow any new fermion to pop up. Anywhere on the side of the graph. Such graph, such graph.  Just some of these main index groups.  Compute. Now, you start with the new way. Okay? But what special about our gauge? Special about our gauge is that no gauge goes on set. So, in our gauge, what graphs can be? This, a graph like this, such as the green circle by something like this. Well, right by diagrams. But these are quite similar to that. Okay? Now, we encountered this class of diagrams before. In somebody's mind, is where we can come. Well, in English theory, except, the large end limit of the scalar theory in three dimensions. Remember, we solved that. And we found that, not exactly this, it was like, like this. But very similar classes of diagrams were invented. Okay? And we used the same method to solve that problem that we're going to use here. Actually, that we used two or three different methods. You can use the same term. Yeah, I'm just going to look at the diagram. You see, all of these graphs, whatever they do, are a sum to give you a self-energy connection for the fermi. Now, any graph here that is separated by a fermion line x, or something else, that just is taken care of with the geometric product. So, the self-energy is just all graphs that cannot be cut by cutting a single fermion line. So, what are we interested in? Something else? All such, we'll get out of this. Okay? So, sigma is the self-energy. I'm going to write down the answer first, without any eyes that might be the sense. Okay? Then I'll just look at the order here. Okay? Okay, you can look at it. Okay? So, sigma is what? You see, all such graphs have the feature that there is an overline end-of-the-pink thing. And inside is whatever you want. If you look at the set of all such graphs, you see, all the sum of the graphs that contribute to the self-energy, every one of them has an overline guide here. Because if it didn't, then there would be a way of cutting through this. And inside is whatever you want. But inside being whatever you want means that this is the exact propagator. The propagator along with the self-energy. You've got the sky for all outside. And here we could have all kinds of things there. Each of these by itself is arbitrary. So, it's the self-energy collection. So, it's free propagator, self-energy, free propagator, self-energy, free propagator, self-energy. What is that? That's the exact propagator. Let me say this again. What is the self-energy collection? It's the term that you add to the effective action. The quadratic term that you add to the effective action. The exact propagator is what you get when you invert the quadratic term including the bare part plus the self-energy. Exactly. So, if now I'm going to write down an equation and you tell me this takes action. Let's know the momentum of this R to follow that is coming from the equation. And let's call this the momentum that goes in here and then the momentum that goes in here here is sigma of P. So, sigma of P of course will be true because I mean a matrix in the speed of this is going to be what's added to the quadratic term for the following argument. So, what is sigma of P? Well, here that is an interaction matrix but the only non-zero a was a lower class or a a upper minus so that comes with a gamma minus is this propagator. This propagator is what? Let's look at f mu into square because a minus is the only so a plus is the only non-zero guy l minus a plus so the only propagator in gauge field is a plus 6 is only 1 gauge field left in a gauge. What is this propagator? 1 over 3 minus. 1 over 3 minus square after some i's and minus s we will try to explain. So, this guy is one of what b minus k minus square. What about this? This is the fermion propagator. The fermion propagator but in tuning signal and therefore this is i p i k slash plus n. What does k have to be k to be anything? Plus minus sign some i's some factors which have to be a little careful about getting explained but that at the end is horse cook. This is the equation. Is this totally? Sir, just one thing I have to understand what is this gamma minus and I will learn another one. There is a gamma minus here there is an interaction here there is an interaction. Gamma minus is the vertex. You see let's look at this. See what do the interaction will take some time. The interaction will take some time for gamma minus. Another way of saying this is the verbeno is contracting this at this but with all interactions that gives us the same that property and we are contracting this in this.  Why? Is the a propagator as an exact signal that connected? No, not just exact signal because you can have this because that is done by one operator. So the larger limit as in this game bear the exact a propagator. It is the same as a bear propagator. The exact psi propagator is not the same as the exact psi propagator. And that is our best a propagator. But it is what it is. These are the two that have to overcome one thing. Is this clear? Yes, I am making. Actually the thing that is written around this equation is through what is called the equation. I will give this to you as an exercise. You take the path you are going to take and then sort of in the bank we need a very similar to that that we used to play the equation. You write on a schindler writing equation for the property I will give you the give this to you as an exercise. Okay. There is a claim there which is this thing that does not stop. But even diagrammatically you see it. Is this clear? Yes. Is this equation clear? So now we are going to take this equation and process it. Okay. So we are going to take this equation and process it. How are we going to do that? Well what we are going to do is the following.  Is to multiply this guy here the sigma here or whatever it is is sum 2 cross 2 matrix. We don't yet know what it is matrix structure is but it can be written in terms of linear combinations. Unfortunately that's not for us. Linear combinations of comma matrices as well as identity. Okay. So whatever it is we improve the identity of the part at the end. We improve the gamma matrix part of the k and we use multiply and divide by such an object to make the denominator simple to get all the matrix structure in the numerator. But now whatever matrix structure we have is sandwiched into the gamma matrices. Now gamma minus square is what can be written. Okay. Exactly. Exactly. Gamma mu and gamma mu are more. It will be 2 give me a name. Now let's you can do it by what you know the simplest way is to just use what J mu nu is in plus minus matrices. In plus minus matrices the metric G plus plus is equal to 0 G minus 0 G plus minus. Okay. So anyway so gamma minus square is 0. If there was a term here of the identity that's 0 of course. If there was a term here gamma minus we know the 0 would be a term here of the gamma plus. Because then gamma plus and gamma minus is now 0. And then that would give us an answer proportional to the left over gamma minus. So do you see that we have argued that whatever sigma is it is all sigma is equal to something that's got little sigma and gamma minus. Because whatever this matrix is the right hand side is proportional to gamma minus and there is no left hand side. Okay. So we started by expressing ignorance about the matrix structure of sigma. But we end up I know the matrix structure of sigma. It's proportional just to gamma. Is this clear? Is this clear? Yes. This matrix equation can now be turned into a scalar equation an equation that's to the coefficient. This little sigma. Okay. So what is the equation turned into? Now I'm writing down all factors of i and so on today and we'll see that i is sigma. Okay. Let me use this. So i gamma is equal to what I think put there one by k squared over k minus integral sigma. Just this and k minus m squared minus k minus and here is purely proportional to what term here is purely proportional to gamma. Okay. The term here purely proportional to gamma minus k plus. That's the sky problem.  Are you understanding? Because you should contract its k mu gamma mu with a g mu mu. It's not proportional gamma minus k plus. We've got another gamma minus. So whatever k plus here gets shifted by this sigma. Okay. In fact, I think it's an idea. So it gets shifted by I take sigma. Okay. And therefore wherever you had k plus, let's write this and let's write this as minus k plus plus. It says that k plus gets shifted by a sigma. And you can ask where does it get shifted by 2 sigma? Does it get shifted by 2 sigma? So what is this? Basically, what is this? Let me check because it's 2 heat glass shifted by sigma. That's somehow to some reason it's very self-active. Okay. So up to such things you see that this is just the shift. Okay. Now when you may when you do the plus minus on top you do the strict denominator numerator this just becomes m squared minus k squared ordinarily. But k squared is a factor of 2 is needed because our square root 2 is okay. But k plus was shifted by sigma. So you get this time. The i epsilon will be discussed extensively. Is that then you have the numerator. But in the numerator only the term proportional to gamma plus contribute. Okay. That did not include our new sigma because that was k minus. Sorry. It did not include k plus because that's proportional to gamma minus. So the only thing that survived was the k minus. And therefore you see there are some factors of two you see that we that this that this 2 pi squared 2 pi squared So this is the integral equation. Now we the integral equation just for the a single single component just check Okay. Okay. So that's I'm sorry actually. Hopefully this discussion on Friday we try to go a little extra maybe. We complete this discussion. Oh sorry sorry about that. I've booked the room by the way booked for I'm sorry to say that actually it's going to be in the US. Yes it is. Let's go. Okay.


Hi everyone. I'm Xin Yang. I'm a technologist from the CEO office of Dell EMC Working on open-stack contributions. I'm a core reviewer in Cender and Manila. I am Jay Bryant And I'm the Cinder subject matter expert from IBM And I'm Sean McGinnis from Dell EMC and I'm the current PTL of the Cinder project Okay So we're going to go through Give an update today of the work that was done in the Newton release I'm assuming since you're here everyone probably knows but Cinder is the block storage service of open-stack. It provides the software API abstraction to be able to manage storage no matter what type of actual Storage device you're using on the back end. So what happened in Newton? We're going to go over our back-end drivers Every release we have different vendors adding support for storage devices Talk about some of the features like async messaging replication Some of these are newer things some are Kind of ongoing work that we've been probably talking about on every update for the last few summits But just things that have been an ongoing effort to get functionality added in Things like active active high-bill ability and then we're going to talk a little bit about our clients We have OS brick our Cinder client and extensions for being able to to do more direct Non-nova more standalone Cinder functionality with a client So every release we get more and more support for different back-ends They just keep coming in every release. So we've got have quite an extensive list now In the last in Newton we were able to add the list here. I won't go through all the names Some of these are just individual devices some are multiple different protocols And a few of these vendors are existing Cinder They've been involved in Cinder and just adding support for our new models So with the addition of these as of the Newton release, I believe this is updated as for our for our final Our final deadline of all the drivers These should be all of the back-ends available in Newton So hopefully if you're using if you're standing up a new cloud or you have existing infrastructure that you're using You your vendor of choice is on this list or if you're looking to deploy a greenfield deployment You can take a look here and see what your options are I do call out a few of here that are Have an asterisk next to him the the LVM driver is the official reference driver of Cinder So if you are a developer working for a storage company, that's thinking about adding a Cinder driver That is the really the best place where we direct people to take a look and see How that driver needs to be implemented? Depending on the type of storage you have there's there's some slight differences So I've highlighted the NFS driver and the sef driver here just because of the type of that Protocol technology things are done slightly different. So if your storage Is a little closer in line to those you can take a look at those drivers as well as good references to see how to implement that functionality so speaking of drivers in Newton we tried to do a little work to make sure that Not only are the drivers consistent and Have third-party CI so that we have some guarantee of at least some basic reliability functionality we added a additional interface checks for all of our drivers to make sure that you Every once in a while we ran across a driver where we added the driver, but didn't find out till later that some piece of it was missing So we have a little more Kind of compliance checking for those drivers just to make sure make sure it's automated make sure that nothing can get in Without us noticing So it's not on it's not up to us or to someone doing the review to notice that we have that as part of the checks that happen when that code is submitted and make sure that we find out right away if There's something missing We also kind of changed our policy around Drivers To give a little background For the last several releases. We've required that in order to have a driver in the cinder tree That vendor or that whoever supporting that driver needs to have third-party CI running You know what that means is anytime any patch is submitted to against cinder whether it's touching that driver code or something completely unrelated That needs to kick off a set of tests run by that vendor against the actual storage device and Make sure that everything passes We do event, you know once in a while catch cases where something that seems completely unrelated Makes a change that ends up breaking a driver So third-party CI is a way to make sure that we catch that right away and don't let that in So with the policy of requiring that what we had done in the past is if a vendor is Unable or unwilling to run third-party CI anymore. We used to remove them from the cinder tree pretty much immediately and There's a set of tags at each project an open stack Says or states to declares that they follow and and one of those takes is follows deprecation And and the deprecation policy for open stack is that any functionality that exists in a project needs to be marked as deprecated for one release Before it can be actually removed in the next release so You know that these aren't necessarily a feature of cinder, but you know drivers are a really core piece of the cinder service So just removing a driver immediately for not being able to follow the CI policy Actually wasn't following the intent of that tag saying that we follow our deprecation policy We would just take it out of there and you know if you were an end user and running a cloud on one of these drivers and You weren't aware of this and you ran the upgrade of the packages for the distro You know you could be in a bad spot where suddenly your drivers no longer there So what we did to address that we you know we we don't want to back off on a requirement of for running third-party CI So we still need some way to enforce that well So to make it a little easier transition and being able to follow that deprecation policy We now just set a flag on that driver That that marks it as an unsupported driver and maybe it's supported by the vendor But as far as the cinder community goes the open source community To us that's an unsupported driver We have no way in knowing as a community whether that actually works or not because we don't have the vendor hardware So we now mark it as unsupported. There's a new option that needs to go in cinder.com That you need to explicitly set To enable being able to run an unsupported driver because we want to make it very clear So that it can't be easily overlooked and then you just run into that problem the next upgrade so we flag a driver is unsupported you Need to make that change in cinder.com and this does make it a little easier if that vendor had some issues and we marked them as unsupported and Now they're able to get back involved in the community and start running their ci We can just change that flag and makes it a lot easier rather than having a whole New driver submission or having to revert all those changes So it ends up being a little cleaner a little nicer on the end user definitely if you're using those back ends and Makes us makes it so we still have a way of enforcing our policies So next I will pass off to Jing So when a user performs a volume operation such as create a volume and and if the operation fails The user will get the status but in order to find out why it fails User will have to dig through the logs, which is not convenient So the purpose for this user message feature is to provide the user with detailed failure messages If the operation fails and then present it in the horizon in Newton We have added ability to list show delete messages The message list can be filtered by resource you your ID resource type event ID and so on And we also have our internal API that you can use to generate a message and save it to the database There's no more work needs to be done to add more messages and make them available in horizon So by default the scheduler will always choose a backend with the highest weight in Newton now we have a new option called the Scheduler weight handler by default that this option is set to ordered Host weight handler it will always choose the host on top with the top with the highest weight but if you change it to Stochastic host weight handler. It's going to make a random selection And there's another change in the scheduler that will affect drivers that supports think theme provisioning support and thick provision support in the same pool previously if the driver supports both same provisioning and sick provisioning support and If the user wants to create a sick long the scheduler will use the logic for same provisioning to evaluate Which could potentially lead to over provisioning so this fix is to add a check in a scheduler to To check the volume extra steps One extra specs if the provisioning type is set to thick then the scheduler will use the Free capacity to to see if there is enough space to create a volume So in newton, we have not done any update in replication API Just we just to have a few more drivers that have added the support. They are Caminario netapps CDOT and solid file drivers So we added a generic volume groups construct in newton So what how is that different from the consistency groups construct that is already in sender? Consistency groups in sender currently only support consistent group snapshot so when we are trying to extend that to support replication group we found that there are limitations because Backends have different requirements some back end can support consistent group snapshot Well other back ends they want to be able to replicate a group of volumes While not maintaining the right order consistency So we couldn't use the consistency group construct to support both And also if a application has multiple volumes It will be convenient if we can group them all together so that user can manage manage them together So that's the reason that's the reason why we added generic volume groups And eventually consistent groups will be migrated to use the generic volume groups similar to volume types and extra specs we added group types and group specs To describe a group only admin can create delete and modify a group type Only admin can set key or unset a key for group specs and view the details of the group specs We now have the ability to create delete update show and list groups in order to create a group you will have to specify a group type And also one group can support multiple voting types So other than the group type you also need to specify the voting types That are supported in this group when you create a group if you want to add add existing volumes to a group or remove the remove volumes from the group then you use the group update command To delete a group if the group is not empty you will have to specify the delete volumes flag So that will delete the group as well as all the volumes in that group If you just want to delete the group itself, but keep the volumes around then you'll have to use the group update first To remove those volumes from the group then you can use the group delete to delete the empty group We also added APIs and CIS to create delete show and list the group snapshots So the group snapshot can either be a consistent group snapshot or they can be just a group of Snapshots that does not have consistency the driver That supports consistency groups currently can add that support using group snapshots By using group types. You can differentiate between different types of group snapshots We we can also create a group from source group or create group from a group snapshot As I mentioned earlier, we are going to migrate consistent groups to generic voting groups So it's going to take a while for that transition to be completed Because this change involves some data migrations We'll need to migrate data from one table to another and eventually Drop in the old table So in order to support rolling upgrades We will have to it's going to take at least I think three releases for this to complete We will provide migration scripts for that. So this is a working progress and we're hoping to get this done in Okada We also have planned to implement a replication group Based on generic voting groups. That's also working progress but because Okada is a short very short release cycle, so We're not expecting that to be done in Okada In center, you can manage volumes and manage snapshots but in order to run that command you will have to provide a Identifier for the volume and snapshot Now to get that identifier, you will have to go to the back end to find out. So now we have this New API to list all the manageable volumes and all the manageable snapshots So and if you list them that then you can take a look and decide what are the volumes and snapshots you want to Bring into under Cinder's control in Utah we deprecated the ability to Define the back end storage in the default section in Cinder.conf If you still use this option, then you'll get a warning the recommended the recommended way is to define them in the back end specific section in the Cinder.conf So we also added the ability to retype between encrypted volume types and non-encrypted volume types and we also Have castelan key manager interface now Castelan is Implemented by the Barbican team is a generic key manager interface right now only the Barbican driver is the Recommended I think production ready driver for for castelan We also added API to update backup a backup's name and description And also now we can delete multiple volume metadata keys using one request We added the e-tax in the API course. So this is a performance enhancement We also we can also query volume Query volumes filtered by Glance metadata key value pairs To use this option you will have to use add Glance metadata to query volume filter option In order to enable that We have also removed XML API That was already a deprecated back in Mitaka Now I'll hand over to Jay. Thank you Shane Okay, so the quota related changes this is a little bit different than some of the other items This was actually an item that was a bug that came in when we added the ability to do higher hierarchical quotas nested quotas in Projects so previously if you were using non-nested quotas if a admin wanted to come in and modify those quotas For the projects they'd be able to do that But when we went to the nested model We had problems that if the admin was not a member of the project They were no longer able to modify quotas for nested projects. So Fixed up the code to check if it's an admin user and then allow them to modify quotas for all the projects on that That system as had previously functioned So not so much a new function, but getting nested quotas working more the way that Quotas had previously worked and that's the wrong button We'll just do this there we go Technical difficulties So that the rest of the things I'm going to talk about here are Items that are continued work in progress Items that we've been working on over multiple releases give you a little bit of an update on how that's going Been doing a lot of work with the active active HA code and trying to get the the functionality of the the volume process Setup so that we're able to have You know multiple volume backends running that you can fail over From a control node perspective so that you know if you've got redundancy on your back end storage Obviously, that's good, but we also need control plane redundancy as we're moving into more enterprise type setups So there's the addition of a new cluster entity where you can indicate which volume back end which volume processes Are clustered together as a a failover unit for high availability? And then adding the commands that go with that and able to to be able to see you know What is the current state of? Those those clustered entities, you know what what what option what backends are clustered together And and that sort of thing so that you can manage your high availability highly available environment There we found in the process Gorka's been doing great work on this lots of API race conditions As far as you know in in consistency groups and when doing migration or retyping extending volumes So there you know analysis and changes that went in to help avoid having race conditions in that code Had to add in the ability to do you know remote locks between between the two clusters So with twos locks added that and then start and stop coordination of the volume service and Gorka's got a great Blog post out there that we have linked on on how you can test Active active and give it a try and if you find issues Please let us know so that we can continue to improve and develop that Multi-attach we actually were just talking about this this morning If you're a fan of cinder and Nova, you know, this is something we've been working on for a long time and so we're we're Been working on improving the APIs to be ready on the cinder side so that we can can Attach one volume to two multiple instances Have them access the same volume On the cinder side, we've got a lot of the plumbing there to do it We're cleaning up the plumbing so that the that it's easier to follow the code path And there's less likely to be issues the challenges on the Nova side Depending on what kind of volume connector you have we have to figure out okay some of them There is for each instance that you attach the volume you have a new connection from Nova standpoint So when you're done with that connection you disconnect it and you know you're done with it And you don't have to worry about it But some of the the back ends support shared connections So you have if you have it attached twice you only see one connection on the host But really it's being used by multiple instances and then it gets complicated from a Nova standpoint to know whether When we disconnect well is that the last person using it or not? So we're working around We have a number of proposals We're working with the Nova team to try to find a solution there that will will work and allow us to do Multi-attached so all of these patches are out there under review We're gonna continue talking about them here at this summit and hopefully hopefully That's something that will we'll go in here in In Okada Rolling upgrades So again, this kind of goes along with all the work to be highly available and working well in an enterprise environment Need to deal with the fact that if you want to keep your Cinder environment up and running while you're upgrading to the next release you need to then Insulate the the volume process and all of cinder from changes that are happening to the database in the back end as the upgrade is happening So there's been a a slow process of moving all of our our different Bits of code all the different objects to a versioned object And what that lets us do is take data and and package it up with the functions That that data is used by and then that insulates it from schema changes on the back end database So These are the the portions of code there. We got updated And we will continue to work through that so that we can get to a full support of rolling upgrades added the new version 3.0 of the RPC API, but it's still backwards compatible with with the 2.x versions So this we're really pretty close to having it all done But like with the active active HA set up There's a lot of testing that needs to be done to make sure that it's really really working and that we're not going to push anything out that That could lead to issues in the future Brick so we continue for those of you that aren't familiar with brick This has been an ongoing project to create a library that instead of having attach code in Nova and Cinder We've created the OS brick project, which is a library that then can be accessed By both Nova and Cinder and we only have to change attach code in one location so you know over the last couple of releases we've been moving to that environment and Now in this release we added more connectors so greater support GPFS now has its own connector so each of these connectors Have support in in brick for any of their special options that they need When they they connect up to a host and so these were added So that they could could support their individual functionality In this release and then also we used move to using privset for privileged operations This was to catch up with Nova and and use the same security solution there for this code and That's something to be aware of if you were running on master at the time as the switch happened you could see some Unexpected changes depending on your environment most people this should just be smooth and Not notice the difference, but it's something to be aware of if after your upgrade you see different functionality in your commands that run as root and Then in the python cinder client just for your awareness. We've really kind of talked about most of this before It was just the addition of the commands to support doing the cluster commands for HA active active support the commands for accessing the message user messages for async jobs and Make you aware that the cinder endpoints command has been deprecated So that that keystone related command is no longer is going to be be removed here and then the new Commands for group types group and group snapshots. So With you with the latest cinder client. We got all that rolled up and pushed out and finally Sean mentioned this a little bit earlier the work we've been doing with the standalone python Brick cinder client the ability to use cinder from from an ironic node not to have to have Nova there in the mix added the ability to actually do a volume attach and detach there so Getting closer to to sharing functionality for cinder on ironic nodes And at this point, we'll hand it back over to Sean to talk more about what's coming in Okada Thanks, so as you've probably heard at least hopefully at this summit The schedule is changing slightly for releases. You know, we've had the six-month cadence forever and As we try to restructure how some of our design activities happen That means that the Okada cycle Really only goes until the end of February And now counting holidays things like that We we really don't have a lot of time in the Okada cycle because of that. I Decided for this release. We had enough kind of long-term feature implementation activities going on You know, we have a few bugs outstanding there so Since it really wouldn't have been enough time to to really jump on a big new feature We're trying to make the Okada release for cinder be mostly about bug fix and stability Going through what issues we have out there. How can we fix them? How can we make things better? so For Okada, there really won't be too much new it'll mostly be You know just a better product better more solid service at the end of Okada That doesn't mean that we're not looking at Both finishing the futures that we've already been working on things like active active high availability This has been a long-term process to try to get all of the those changes in place We hope to finish that in Okada rolling upgrades the rolling upgrades are Pretty much complete the only reason we still have any hesitancy to just say yeah this rolling upgrades are good Just we want to improve our automated testing around that make sure that we have everything covered but everything's in place and As we mentioned before the multi-touch activity with Nova changing You know that whole effort just how it Really highlighted some of the issues we had interacting between Nova and cinder We're really hoping that we can do something for that in Okada You know maybe we might end up being one of those that we talk about again at the next summit But we want to iron out how that interaction works and really come up with a solid API solid plan for What's going to work well between Nova and cinder so that we can actually implement this multi-touch support? with a sane API so well Here's a related links, but but on the topic of Upcoming things beyond Okada. I just wanted to say we are discussing that we are seeing What other functionality we need to start thinking about for the pike release and beyond that? We have some ideas as a cinder team But definitely this is a great time great opportunity if if there's some functionality in cinder missing that you need for some to meet your use case Please talk to the team Go on IRC send to the mailing list Track me down We'd love to get any feedback from operators to players. What kind of issues are you running into a cinder? What do you need in that service to be able to to give a good solid storage API for your cloud? so with that I'll ask Jing and Jay come back up on stage and we'll open it up for any Q&A we got it all covered Thank you Yeah, so so the question was if we have a driver with That doesn't currently have consistency group support. What should that driver vendor plan to do? Yeah, I should just use the the new CLI the new API is actually that there is a driver interface for that Just implement the new driver interface Yeah So you can you can you know In your driver, you can use different group types where you can say you can report the consistent group snapshot you could do true and you can You can use that to add the support So you're in your driver you can just Call your special API that create the consistency group snapshot and you can actually support both so You can depend on the type. It's either Consistent or you know the just a group of volumes and groups of snapshots that are not consistent You can support both depending on the type that actually I don't know if we have new vendors or vendors in the room that are considering adding drivers, but You know given how quickly the list is growing. I bet you there's a decent chance of it So we still have the you know something that hasn't changed Here in Newton is you know, we have the list of Expected functionality that every driver has to implement to be included in Cinder. We have not added additional function to that since gosh Probably ice house now You know, but but one of the questions I get internally from all my IBM driver people is What do we need to add? And really, you know, not every back-end supports consistency groups or the other functionality And it's really up to the vendors as to when these new functions are made available in Cinder When they want to implement it and and that's you know, we've got a matrix out right now If you search for it that shows the least how we understand the current state of Drivers and what functions they support, but that's definitely an area that we can Continue to improve on but I would I would ask back to you You know if you add consistency groups for your drivers make sure that that's that's documented and indicated so that we know what each driver Is supporting other questions That's a good question. Thank you. Well, thank you. Thanks very much


Hey guys it's Julia and welcome back to my channel and for today's video I'm going to be talking about some of my favorite TV shows and films from the year of 2017. I have that many to talk about but I'm only bringing up stuff that came out this year or like a new season came out this year as opposed to like older movies I've watched this year so let's get into it. So starting off with films first of course I have it by Stephen King the movie obviously. I'm so used to saying by Stephen King because I always talk about the book but I love the movie so much I have a whole video about it but that movie was just I was it was funny and it was just everything. And my last film like new film that I saw this year was Before I Fall and this is also based off a book it is based off of Before I Fall by Lauren Oliver which is about a girl who lives the same day over and over again after she gets into a car accident. So that's what this is about. I really like the film I thought it was there's definitely some perks and some cons to the film but overall I ended up really enjoying it. Giving a few little bonuses to movies that I just watched this year that didn't come out this year that I loved. Horse Gump, The Shawshank Redemption, so many that were so so good so like I don't know. There was so many and for TV shows which I have more of to talk about. First up if you guys don't know I love the show The Young and the Restless is a daytime soap opera thingy it's on every day for about an hour. I tend to watch it every day or I will just binge it one day. I watch it with my mom and I just love this so sh... I just love that show so much it's filled with so much drama it's just it's a good show it's entertaining like once you start you're you're you're done. Like I've been watching it for years.  I'm still like I'm sitting here waiting for that mid-season we like we just had the mid-season finale so I'm just waiting here like okay where's the rest? Like hurry up January. I want the next half of the season for Riverdale. That show is so good. It's a mystery mostly mystery hot men. I'm there. Next is Stranger Things which of course you guys know I love. I'm gonna link my video up on the screen. I really enjoyed season two I thought it was different from season one obviously but I thought there was some really good things about it and I liked some of the new characters we were introduced to. Sorry cat Rudy say hi okay bye. Next is American Dad which I discovered this year so good so amazing love it actually I don't know if I was watching new episodes but I'm counting it.  I have Bob's Burgards, The Simpsons, Family Guy, all those amazing shows I loved watching this year so this year was a great year for film and TV series just a few more honorable mentions to TV series that didn't come out this year but I still loved Hannibal my favorite show ever I watched it many times oh I forgot to talk about criminal lines those new seasons are on I really enjoy that show obviously it's it's literally my favorite show of all time battling with Hannibal a little bit so yeah so there you guys have it that was my little video about my favorite TV shows and films that I watched in the year of 2017 let me know your thoughts and some of your face in the comments down below and I'll see you all very soon with a new video bye


I have discovered an app that can help you to assess lots of technical analysis indicators for free. The best part is, whether you are into stocks, commodities or indices, this app got 230 options for you. This app is none other than OptaFX, a global poker that offers a wide range of trading options. Today, I am here to spill the beans of these three incredibly powerful technical analysis indicators that have been my secret weapons for optimizing my trades. And how you can use OptaFX to assess these indicators easily. By the time we are done, you will be much more equipped with the knowledge to trade confidently and smartly. Oh, don't miss out on the third indicator. It's a game changer even if you are completely new to the trading scene, because it's so simple yet effective. So make sure you watch this video till the end. Hi everyone, this is Chloe and welcome back to my channel. Have you ever wondered how experienced traders seem to have the sick sense about market trend and price movement? It's like they are having a crystal ball for knowing when to buy low and when to sell high, ensuring they back the profit while minimizing losses. Guess what? It's not magic and luck has nothing to do with it. It's actually about technical analysis. Before we dive into these indicators, let's tackle an important question. Is learning technical analysis really worth it? Well, if you are in it for the long haul, like our investing guru, Warren Buffett, who looks a decade ahead, you might not need it. However, if you are more into short-term trading, buckle up as technical analysis is key to trading success. You see, trading isn't about blindly buying and selling assets, it's about understanding the underlying factors that affect the price movement. And that's where technical analysis comes in. By analyzing historical price movement, chart patterns and various indicators, you gain a deeper understanding of how the market moves and potential turning points. It's like starting the path to project into the future. Imagine being able to spot potential breakout, trends, reversals even before they happen. But it's not just about prediction. Technical analysis empowers you to manage your risk effectively. You will be able to set stop-loss and take profit level based on solid analysis rather than guessing blindly. This level of planning can make a wall of difference in preserving your capital and maximizing your profits. The best part, technical analysis isn't limited to a specific market. Whether you are into stocks, cryptocurrencies, forex or other asset classes, the principles still apply. It's like a universal language spoken by traders worldwide to decode the market's behavior. 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Their support team is there 24-7 to answer all your questions. And handling your money is a breeze at OctaFX. Deposit takes just a minute and withdrawal rolls are under 49 minutes, even faster than your food delivery. So if you're ready to kickstart your trading journey safely, keep the link in the description or scan this QR code to download OctaFX trading app. My promo code, Aligato, allows you to double your deposit for trading. Now let's get back to the video and let's start with the first indicator, MACD, Moving Average Convergence Divergence. Think of MACD as a market detective. It's like having a special tool to help you spot potential trend changes before they are even obvious. There are various ways to use it, but I like to keep it simple by focusing on the color pattern of the histogram. Imagine MACD histogram as a traffic light that has 4 color patterns. Green, light green, red and light red. When it's green, the trend is bullish. Any car can drive through during that time but when it turns red, that means the market is flourished where all the traffic needs to be stopped. But here's the trick. It's not just about identifying bullish or bearish trend. It's about spotting the change in trend direction. Have you ever encountered a situation that you thought that the bullish trend is intact and the prices would just keep on going up? But the moment you enter your trade, the prices start to fall. Or vice versa, have you ever experienced that the moment you decide to cut loss and exit your trade, only to realize that the market has bottom and the price start to go up? All these can amount to painful losses and that's why by using MACD, it can provide you with better insights in terms of the trend reversal. That's why when looking at MACD histogram, instead of focusing on the green or the red, we should focus on the light green and light red portion because they signal a change of trend. How to add MACD into your OctaFX trading app? All you need to do is to click indicator and select MACD. Immediately, you can see that the MACD chart is being added inside your OctaFX app and from this chart, you can see that from red, the histogram is turning into light red and at the same time, the histogram is sloping up. It indicates that the bearish sentiment is about to change. And indeed, right after that, the stock price started to pick up and in this another chart, you can see that at first, the stock price was very bullish and the green bars in the MACD histogram was very tall and very full. But the moment light green bars appear and started to trend downwards, the stock price started to fall. So one easy way to remember how to use MACD is think of the bull and the bear in terms of size. When the bars are all green, the mommy bull is super strong and big and that's when we need to be careful and watch out for potential trend changes. And when the bars become light green, it shows that the mommy bull has retreated and now only left with baby bull. So the baby bull trend in comparison is a lot weaker and this could be a good time to sell and take profits. And it's definitely not the right time to enter bullish trade. On the other hand, when the bars are super red, it shows that mommy bear is super strong and most traders are getting super scared with lots of panic selling. That's when we need to be greedy and prepare for potential bullish reversal. And the moment mommy bear retreats and the light red baby bear comes in, it shows that the market is now less bearish and has momentum to trend upwards. And as you can see right after, the stock price started to go up. Now remember, while MACD can be a very powerful tool, it's one piece of the puzzle that traders use to make more informed decisions. That's why to sharpen our weapon, we need to go into the second indicator. RSI, Relative Strength Index. Your gauge for when a stock is oversold or overbought. It's a number ranging from 0 to 100. When RSI is high, that means close to 100, it suggests that the stock is overbought and ready for a pullback. Picture it like the latest nickel trend. When everyone rush to buy, the prices guy rock it. But eventually when people wise up and demand start to drop, the prices will start to fall. Basic supply and demand isn't it? And this is where a high RSI comes into play, indicating a potential slowdown in buying enthusiasm. So how to add RSI into our OctaFX app? All you have to do is click on indicator and search for RSI. After clicking that, this chart will be added into your app. As you can see from this chart, RSI is now being overbought and right after, the stock prices start to fall. Conversely, when RSI is low, which means close to zero, it's the opposite scenario. Just like sneakers going on sale and nobody's there to buy, eventually the prices fall to the level becomes no-brainer for anyone to buy. And that's when buying started to happen and the snaker price eventually go up. So in this scenario, an oversold RSI hints a possible bounce or recovery, signaling that selling might temper off soon. When prices keep falling and RSI reach an oversold region, prices eventually started to go back up. Now if you think RSI and MACD are super helpful, wait until you see the third indicator. And it's so easy to use that even beginners have no problem spotting the pattern. So here comes the final indicator, Boilinger Band. Imagine that yo-yo that bounce back when it drops too low. Boilinger Band operates similarly that way. The upper band acts as a ceiling. When the prices approach it, they might struggle to go higher and the lower band acts like a floor. When prices approach it, they tend to bounce back. So how to add Boilinger Band into your Octavex? All you need to do is once again click indicator and search for Boilinger Band. As you can see from the chart, when the stock price touches the floor, which is at the lower end of the band, the prices usually trend up. And vice versa, when the prices reach the higher end of the band, the stock price starts to come down. So by using this simple indicator, you can learn how to enter and exit your trades better. And the best part about technical analysis is, you can combine all of them together to make your trades even more effective. When I add all of them into one single app, things become even more holistic. From this chart, the MACD, RSI as well as the Boilinger Band are all telling me that the stock price has almost reached its full bull momentum. And I expected the prices to fall. That's why I won't be entering any bullish trade right now as the risk is a lot higher. Instead, it could be a good time to take some profit off the table. In a nutshell, MACD can help you to see whether a trend might be changing direction. RSI helps to see whether things might be getting too extreme with buying and selling. And the Boilinger Band helps you to focus the stock price movement range ahead. However, it's important to note that all these indicators aren't foolproof. No single indicator can guarantee you 100% accuracy, so the key lies in using them wisely and honing your skillset. On top of these three indicators, there are many other useful technical analysis indicators out there, including Ichimoku Cloud, Moving Averageers, Stoicastic and more. All of them can be found inside OctaFX Trading App and will come in really handy if you know how to combine all of them effectively. So if you want to get started your training journey the smart way and get access to all these free tools and resources provided by OctaFX, all you need to do is to open a free account with them via the link below. If you like today's video, remember to give it a thumbs up and share it with your friends. Do join my Telegram channel so that to get more investment updates as well. Until next time, happy trading, and I will see you in the next video. Aligato!


Felly yw Josephine Phillips, a rwy'n gwnaeth ymdeithasol, sy'n eich bodi ymddydd o'r ffordd o'r ystafellau o'r cymdeithasol, ac mae'n hwnnw i'n ffwrdd o ymddydd a'r wast o'r cymdeithasol. Rwy'n mynd i'n rysgol i Gagri, yr ymddydd o'r cymdeithasol, ac mae'r cymdeithasol yn ymddydd o'r cymdeithasol a'r ymddydd o'r cymdeithasol, a'r gwahanol cymdeithasol a'r cyfwyr ar y cyfwyr. I'm Isabel Goff. I'm CEO and co-founder of Circular and we deliver carbon metrics to the built environment. Just in my orange power, we're trying to turn every house into energy storage. So what that will do is that we empower all the renewables connected to the system and then we can help out the grid when the grid is really struggling with the renewable intermittency. My name is Aiche Dündar. I'm the CEO and co-founder of Soloblw. At Soloblw we are making edible packaging made out of seaweed that also extends shelf life of fresh food. The biggest driver for motivating us to keep going on our start-up journey every single day is the fact that we're going to make a change. As we see every single day that we're doing repairs and iterations, increasingly we know we're going to make a change in the fashion industry and that's definitely the biggest motivator. So what drives us on our start-up journey really is the fact that we're making instant impact, whether that's reducing energy waste or improving the air quality and health and wellbeing of our occupiers and tenants. We're starting to see more and more of the biggest historical polluters in the industry coming to us saying we want to do everything we can to be more sustainable and reduce our impact. So seeing those people step up and want to lead us towards a more sustainable built environment is just so encouraging. The biggest challenge that we're facing at the moment is definitely a lack of carbon data and for us it's the lack of upstream carbon data. So pulling the R&D lever is something that we need to do pretty immediately in order to support innovation. So we are like all the other start-ups so we are facing the challenge of how to attract the right talents and how to get the best product for customers. I started my company in my kitchen. We didn't have everything that we needed, we didn't have the expertise that we needed and we didn't have any big teams so our team grew gradually but all the knowledge that we learned along the way was from other start-ups. That's why Canada Pay Hub is a really good environment for us to be able to brainstorm with other start-ups or even big companies. It's sort of showing the future of where we're going in terms of how it was built and how it was created in such a sustainable way but also it's really exciting that space is being created for these kinds of businesses and these kinds of initiatives. It's really important that what's happened here on the retrofit side of things is showcased and other people can learn from this and hopefully that pushes the industry forward. Ultimately we want to be in the position where this is the norm. It's a great building that's also embraced all the modern technology and also the concept of net zero as well as sustainability and that basically gave us a new level or a good example to say what we should do in terms of retrofit and modern building. Company is based in Cambridge so it makes a lot of sense to be able to pop in and have a desk space there and to brainstorm with other start-ups in the building but at the same time we can invite our clients to show where we work. It's an incredibly lonely journey when you're a start-up and you don't know how to do things so connecting to other like-minded businesses is really incredible but also connecting us to other individuals and industry experts and leaders and business people who can really help bridge that gap into the sector and improve us is really exciting. It is bringing together this community. It's always really useful to have that energy in the same room but also people going for the same mission. Access to capital, access to talented, knowledgeable people and access to potential partnerships is what drives innovation and start-ups. There are funders about two or three years ahead of us holding our hands in terms of fundraising, technology, et cetera and also a lot of good advice from the whole community, a wider community of CSL.


Thank you all very much for having me here today, a little bit different topic I suppose and we've started with so far, but I'd like to talk to you today about continuous flow bad support in the fontan patient objectives today I'd like to talk about a little bit of the anatomy lesson of what the fontan looks like issues we see with the fontan circulation. And then what we kind of describe as fontan failure, we'll go over some experience from Dell Children's, then also talk about what's coming down the pipe, excuse me. Starting off kind of how we get to the fontan circulation we'll use hypoplastic left heart syndrome as an example. I mean that's where we utilize the norwood procedure, and then also deliver pulmonary blood flow via the blade left tussig common shot. Just as a kind of side note there's a great movie to watch if you'd like to something Lord made. It's a great story about the three kind of developers of this process. Vivian Thomas is kind of one of my, you know, kind of heroes, if you will, a guy that self taught and raised himself up to basically invent the procedure and show Dr. Blaylock how to do it. And as we are in hallowed ground here, Dr. Cooley himself participated in that very first surgery. He's in that picture somewhere I'm not sure which character. So moving on, sorry, focus. Going back to the next phase of the kind of a trio of surgeries, the Glenn circulation is set up by attaching the SBC to the pulmonary artery, further offloading the ventricle and advancing the patient to the next phase, then next phase with final variation of the hyperphysically tart syndrome surgery pathway is the total cable pulmonary connection or the IBC is eventually connected to the pulmonary artery with the Glenn procedure separating running in parallel those surgeries there, the those circuitries they're providing a fully oxygenated patient. So this procedure so the fontan procedure was originally described by Dr. Fontan in Paris in 1971, later refined and described by Kutcher in Argentina and 73. This is a paliation for the functional or an anatomical single ventricle. Some of those examples are hypoplastic left heart syndrome, tricuspid atresia pulmonary atresia intact ventricular septum son of the original procedure was really focused on tricuspid atresia described the process as connecting the right atrial appendage to the pulmonary artery the thought was behind this was the contractile function of the right atrium augment flow through this process. What was discovered over time and Dr. Frazier and I have personally done many of the fontan conversions if you will. The right atrial distention thrombus formation in that and eventually leading to a rhythm is really landed this procedure to many problems. Later on developed was the inter cardiac fontan where the baffle was placed within the common atrium where the IBC was then baffle through to the SVC that was connected to the pulmonary artery. This later became known as the total cable pulmonary connection which developed later and the one we use most commonly now is the extra cardiac fontan using a PTFE graph from the IBC to the pulmonary artery. The benefit of this it kind of remove the suture lines in the right atrium and maybe made much more kind of a continual pathway there. So a little bit about fontan mechanics that kind of cause some of our problems here if you think about the normal heart ejecting from the LV coming across through the aorta delivering pressure and flow to the systemic circulation passing through the pulmonary beds, and then eventually coming to the right atrium and pressure of, you know, two to eight relatively low coming through the right ventricle pressurizing and being Val. Going through the valve pathway, you increase your pressure to the pulmonary arteries to that, you know, 18 ish pressure, then therefore providing a gradient from the pulmonary artery or cross along to once again a low pressure left atrium, and then starting to cycle over again. With the fontan circulation, you're creating a situation where you're increasing your central venous pressure to that pulmonary artery pressure required once again to create that gradient across your lungs. And this is kind of the the net of all the problems of the fontan circulation required, but can cause problems. What are all the problems. The complications we see in the fontan circulation. The one most noting mind you this isn't all fontans but is a good chunk of these patients. And when we're talking about circulatory support to transplant this is some of the things we definitely see in this population. You're losing interopathy where that lymphatic leak into the gut due to higher than normal venous pressures in in the environment of a low pressure lymph system pours off that fluid into into those organ systems, those proteins being albumin coagulation factors in you know, and then of course immune compromise and then leading to poor healing. So an exacerbation of many problems. Guess what this happens in the lung. So, so the cells back on itself coagulopathy is due to factor loss growth delay albumin one of the primary carriers transport mechanisms for calcium for bone density, and then of course immune compromise, and then leading to poor healing. So, an exacerbation of many problems. So what this happens in the lungs to so plastic bronchitis. So that once again that spillage of protein rich lymph into the airways causes developing of thick cast and the limit of the airway. This can lead to severe I mean this is blocking of the airways progressively so severe hypoxia X fees this is a that word. And also potentially I even leading to death. These can typically or sometimes be removed from bronchoscopy, or even patients can cough these up. Now if you cough that up I might just be I don't know if I could pass through that. Other problems we see with these patients once again do the higher venous pressures we have fontan associated liver disease so lymphatic overflow and congestion of the liver as well. It can lead to esophageal varices societies, fibrosis and cirrhosis of the liver. And once again because of the poor sense system disease of the liver we can have coagulation abnormalities. You can kind of see kind of some recurrent themes of feedback mechanisms that cause some of these problems so the fontan failure can kind of be described in two different pathways the circulatory failure where we have these elevated pvrs and mind you all these are much of these patients end up being on high levels of phosphodescase five inhibitors and the subgenophils that the dialyphils and even both sent in to get those pvr and the resistance down through the lungs. Hydrostatic pressures, the pressures within the fontan circulation are very variable to standing and laying and so on and so forth obstructions within the circuit itself these are not straightforward surgeries. There can be a lot of energy loss, especially in the, the extra cardiac or the inter cardiac fontan where the atrial wall can be very modular and change shapes. Some, sometimes there's a lot of stasis when these, in these circuits, and with this we have potential progressive cyanosis and the development of auto pulmonary collateral. So on the other end of things, not the circuit or the plumbing of the process, the pump itself can become a problem. Many of these patients, especially in the hyperplastic left heart syndrome pathway. We're using a systemic RV RV to create the higher pressures that an LV would be accustomed to. This is not a long term strategy and we almost always see some kind of dysfunction in these LVs long term. We have developed some of the low cardiac output, we can develop cyanosis in this. And of course, with low cardiac output develop endorphin dysfunction they can lead to other problems so you can see there's kind of feedback mechanisms here that we can't really get around. The one thing we can do or try to do is fix this problem. And we can do that with mechanical circulatory support. We share kind of our, some of our experience Dell Children's Hospital in Austin, and keep our kind of motto in in check. Our last two four years we are excuse me two years we've done four patients, all of them single ventricle for our continuous flow devices. We had an 11 year old with a herotexilla and balanced AB canal. We poured a heart where in 19 year old extra cardiac fontan with a heart where 12 year old with a extra cardiac on time with the heart and three. And then now we currently still have on a 13 year old with extra cardiac fontan awaiting transplant. All the previous patients have been transplanted successfully. I'm going to go over the first patient real quick, because she was unique. So we had a 11 year old with heterotaxi unbalanced AB canal. She had a fontan in 2019 about 10 years after that she came to us with worsening heart failure during her stage you kind of be evaluating worked up for transplant, but she had a cardiac arrest. It was a great deal. We had really hard time getting access. She had scar and every vessel in her body. So they're very prolonged CPR event she did get on successfully onto ECMO. We did take her to CT to kind of check some of the boxes make sure okay, we did see some sub acute cerebral infarcts, but nothing that kind of really indicated that it was a no go. We even woke her up on ECMO to make sure we could get some level of neurologic exam. Another challenge. We actually implanted this from the right atrium to the aorta. We did this for a few different reasons. One, I just say we had 120 minutes of CPR. So the chest was really beat up a lot of hemorrhaging in there already should have been on ECMO for seven days. And also the fact that this is all these patients are 345 time redo sternotomies. So the scar level the adhesion level within this chest was immense and everything was bleeding. So to dig out the ventricle to implant this in a normal fashion was was really not an option. So that was one problem. Also part of the problem is because of this heterotaxi and the unusual kind of structure and architecture of the aorta or excuse me AB valve, we really couldn't fit something into a apex on this relatively small heart. So the choice was to go through the right atrium to the ascending area. This is kind of in a unique way because we didn't do it on bypass. We were already on ECMO so utilize our bypass pump on standby as kind of a dairy mechanism so my colleague Tiffany Rob wrote this up nicely last year. So the rest of our patients we did implant in what the relatively normal pathway, we did put the pump in the systemic ventricle. What the systemic ventricle was a right ventricle, which is full of heavy tribulation, kind of a perfect night is for one pump occlusion, and also for thrombus within that ventricle, low heart failure patient, low cardiac output patient, a lot of the ventricle, we had to be very careful to kind of make sure we didn't have any to make our excuse me thrombus within there. So the second problem we see in these patients is we're going to put the aortic anastomosis, this whole ascending order has been mutilated.  So you have to find a place to fit this graph so that's a challenge as well. So also challenge you to see this, see with these patients, for example, our patients three and four aortic insufficiency of that unacceptable you just create a feedback loop within the heart and within the bad is unacceptable anything other than mild, we have to address. You can address that with aortic valve repair, aortic valve replacement, or you can even just close the aortic valve LBOT that definitely increases the risk of thrombus formation. The problem with this once again like I just said, this aortic root this ascending area is a God awful mess so we have to think about what that looks like it to skeletonize the aortic outflow track to be able to do a aortic repair, which causes another level of a hemostatic problems, and also just the different tissues so we think about that and time on bypass. So what did we do, we employed a park stitch for two of these patients so that's a central stitch proximal nodules or Antias, I was kind of like saying or Antias is fun. So what this does is due to this large amount of AI during diastole, it brings those that center portion of the valve together and makes it competent so that the the aortic insufficiency is solved, and it also allows some level of opening of the aortic tractors to wash the valve out and allow some flow in there reducing potential thrombus around that outflow. So we employ that in two of our patients. So how do you know where you end up being on RPMs and flow in these patients. So typically, especially described in the adult population, you do a ramp study. So you do this using echocardiography, you observe the septum position so moving left or right depending on the offloading of the LV, LV size to understand if you're properly offloading. How often is the already valve opening determining the pressures across that area right valve and increase RV pressures if you're not offloading the LV properly, then it backs up into your RV you're going to have problems with that. Only one ventricle. There's no septum blow gap for position, very little reference on what size ventricles are going to be proper, and you very well may have a park stitch in place so you can observe that area valve opening properly. So, we took these kids to the cat club. So wanting to make sure that we had therapeutic anticoagulation in place and anti or platelet inhibition properly want to make sure there's no thrombus within the LVOT that we're going to mobilize. So we had a lot of realization between these changes we had to make sure and kind of sit on our hands in a little bit and let them let things stabilize with the very kind of compliance of the Venus system. These changes take a little while to kind of get to where they're going to end up being so we started by lowering the RPMs of the devices until the AV valve opens or every every beat or looking at the AV valve research increases. So all these values and documented them and trend them throughout the process looking at the bad settings. Pulsatility index on so forth, looking at pressures along the fontan circuit, and also looking at saturations and then actually looking at those structures and seeing how they react to these changes. So these are the 20 results to be very straightforward and honest so this is our hardware patient we weren't able to kind of stimulating circumstances with our first patient weren't able to do a ramps a second hardware patient. We ramp them all the way from 2400 to 2900. I don't know if you notice though, pretty flat lines, we really didn't see any exciting changes that we could dial this into the similar things with our heart mate three patients. You can see the CVP or the fontan pressure stayed pretty much flat. The capillary wedge pressure your left atrial pressure stayed pretty flat, and we didn't get a huge bump out of any saturations as well. So our fourth patient very similar process. So one thing we kind of had to go by was that AV valve regurg since also we can really look at the aortic valve so we looked at the aortic AV valve regurg and then dial back just appropriate to keep that in check. So sometimes we have to always think about kind of these feedback loops. So we have this relatively fixed PBR in these patients. Like I said they are on pulmonary vascular resistance reduction meds. We can't be too aggressive to overflow the pulmonary system and create pulmonary edema in by going faster and faster and kind of sucking the fontan dry, if you will, we increase those Venus pressures and cause more problems and always have to think about what's downstream from all this. So we have higher Venus pressures by increasing the flow of the bad we can't decompress the lymph system as well. If you remember the thoracic duct dumps right into the inominate vein, which if we're pressurizing that valving system can't work properly and decompress the the lymph system. So where is the sweet spot of the QPQS with these with these bags.  There's not perfect place to be the key points that we found in these patients to get them in that sweet spot, make sure we're offloading the AV valve regurg ample cardiac output to maintain an end organ function, primarily renal make sure and balance their volume volume or volume status and also get to make sure we get quality nutrition in there, and also that we're not overflowing the lungs. So the good news is, hopefully there are some things down, down in the future that will help us with this, the group of chop has reported successful use of total artificial heart and failing fontan circulation. And this is quite the undertaking those of you participated in these. But that does solve the problem there's a pump and there are valves on the side of the circulation now, the taste care of this but this is definitely a one way pathway to transplant. So in the lab there's still some work that's very exciting stuff there's some centrifugal pump systems that kind of decompress the SVC and IVC circulations and and push into the pulmonary circulations. So far so good but they came across a few problems that were nicely defined by the road fell group that has been working on this I remember seeing the first presentation, I think in like 2002. So, this group has been working on this long and hard. One thing they really define in their processes and their research was that you have to have a passive system as well. So if the system, the pumped mechanism or the artificial portion of this fails for any reason, you still have to have open pathway and passive pathway for your blood flow. We're coming out coming down the road, but I'm excited to be here to be talking about this because I know for a fact that there's some of this work going on right here in the Texas Medical Center. So hopefully we can see some advancing of some of this as well. I encourage you to come visit us in Austin sometime we're growing in a fantastic program. I'd like to give a big thank you to Texas or and this is exciting that we're at a 60th anniversary of Texas our Institute and 50th anniversary of TTI perfume. What I learned here and what I was exposed here, and I see a lot of really familiar faces that learned me brought me to where I am today. So thank you all very much.