{"action":"created","issue":{"url":"https://api.github.com/repos/dart-lang/sdk/issues/25188","labels_url":"https://api.github.com/repos/dart-lang/sdk/issues/25188/labels{/name}","comments_url":"https://api.github.com/repos/dart-lang/sdk/issues/25188/comments","events_url":"https://api.github.com/repos/dart-lang/sdk/issues/25188/events","html_url":"https://github.com/dart-lang/sdk/issues/25188","id":121216632,"number":25188,"title":"Performance issue during the debug process","user":{"login":"krkboasit","id":16207464,"avatar_url":"https://avatars.githubusercontent.com/u/16207464?v=3","gravatar_id":"","url":"https://api.github.com/users/krkboasit","html_url":"https://github.com/krkboasit","followers_url":"https://api.github.com/users/krkboasit/followers","following_url":"https://api.github.com/users/krkboasit/following{/other_user}","gists_url":"https://api.github.com/users/krkboasit/gists{/gist_id}","starred_url":"https://api.github.com/users/krkboasit/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/krkboasit/subscriptions","organizations_url":"https://api.github.com/users/krkboasit/orgs","repos_url":"https://api.github.com/users/krkboasit/repos","events_url":"https://api.github.com/users/krkboasit/events{/privacy}","received_events_url":"https://api.github.com/users/krkboasit/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/dart-lang/sdk/labels/area-dartium","name":"area-dartium","color":"c7def8"},{"url":"https://api.github.com/repos/dart-lang/sdk/labels/vm-debugger","name":"vm-debugger","color":"d4c5f9"}],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":2,"created_at":"2015-12-09T11:32:17Z","updated_at":"2015-12-11T22:12:47Z","closed_at":null,"body":"## Summary:\r\nThere seems to be an issue related to debugging web applications using dartium. \r\nWhen resuming program execution after triggering a break-point, performance becomes significantly worse under specific curcumstances.\r\nWhen execution is resumed by stepping out of the event-function (i.e. we do specifically not click 'resume program'), the application becomes noticeably slower from that point on and forward.\r\nRepeating the process further degrades the perceived performance each time.\r\n\r\n## What steps will reproduce the problem?\r\n1. Create a new project by cloning the link: https://github.com/dart-lang/sample-pop_pop_win.\r\n2. Open lib/src/stage/square_element.dart.\r\n3. Place a break-point at line 82, this should be the closing brace of the onClick() function.\r\n4. Run the application in debug-mode.\r\n5. Click on a balloon.\r\n6. Press F7 or F8 to perform a step into or step over action and out of the debug process.\r\n7. Repeat step 5-6 until the application starts to perform noticeably worse.\r\n8. Remove the break-point and repeat step 5.\r\n\r\n## What is the expected output? What do you see instead?\r\n__Expected:__\r\nThe application will run smoothly throughout the debug process.\r\n\r\n__Actual:__\r\nThe application starts running slower and slower the more times you exit the debug process\r\nby performing a step into or step over action.\r\nThe issue remains even if the break-point is removed.\r\n\r\n\r\n## What version of the product are you using?\r\nDartium dartium-win-full-dev-1.14.0-dev.3.0.0\r\n\r\nWebStorm 11.0.1\r\nDart 14.0-dev.3.0\r\n\r\nOn what operating system?\r\nWindows 7 SP1(64bit)\r\n\r\n## Please provide any additional information below.\r\nThe issue has been reproduced using dartium-win-full-stable-1.13.0.0\r\n\r\nRemoving the break-point will not fix the issue, but restarting the debug process will reset the performance.\r\n\r\nPerformance seems ok if the debug process is exited by pressing F9 to perform the resume action,\r\nhowever this does not reset the performance and exiting the debug process with F7 or F8 afterwards will not have improved performance.\r\n\r\nAdditionally we have observed the application crashing on several occations during this process.\r\n"},"comment":{"url":"https://api.github.com/repos/dart-lang/sdk/issues/comments/164063473","html_url":"https://github.com/dart-lang/sdk/issues/25188#issuecomment-164063473","issue_url":"https://api.github.com/repos/dart-lang/sdk/issues/25188","id":164063473,"user":{"login":"alan-knight","id":3476088,"avatar_url":"https://avatars.githubusercontent.com/u/3476088?v=3","gravatar_id":"","url":"https://api.github.com/users/alan-knight","html_url":"https://github.com/alan-knight","followers_url":"https://api.github.com/users/alan-knight/followers","following_url":"https://api.github.com/users/alan-knight/following{/other_user}","gists_url":"https://api.github.com/users/alan-knight/gists{/gist_id}","starred_url":"https://api.github.com/users/alan-knight/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/alan-knight/subscriptions","organizations_url":"https://api.github.com/users/alan-knight/orgs","repos_url":"https://api.github.com/users/alan-knight/repos","events_url":"https://api.github.com/users/alan-knight/events{/privacy}","received_events_url":"https://api.github.com/users/alan-knight/received_events","type":"User","site_admin":false},"created_at":"2015-12-11T22:12:47Z","updated_at":"2015-12-11T22:12:47Z","body":"This is about the Intellij debugger integration, which is using the deprecated VM debug protocol. This should be replaced with the observatory protocol before long, which would presumably make this obsolete. @jwren @rmacnak-google "}}