{"action":"created","issue":{"url":"https://api.github.com/repos/aspnet/EntityFramework/issues/5254","repository_url":"https://api.github.com/repos/aspnet/EntityFramework","labels_url":"https://api.github.com/repos/aspnet/EntityFramework/issues/5254/labels{/name}","comments_url":"https://api.github.com/repos/aspnet/EntityFramework/issues/5254/comments","events_url":"https://api.github.com/repos/aspnet/EntityFramework/issues/5254/events","html_url":"https://github.com/aspnet/EntityFramework/issues/5254","id":152618758,"number":5254,"title":"Investigate async query test failure on Linux","user":{"login":"natemcmaster","id":2696087,"avatar_url":"https://avatars.githubusercontent.com/u/2696087?v=3","gravatar_id":"","url":"https://api.github.com/users/natemcmaster","html_url":"https://github.com/natemcmaster","followers_url":"https://api.github.com/users/natemcmaster/followers","following_url":"https://api.github.com/users/natemcmaster/following{/other_user}","gists_url":"https://api.github.com/users/natemcmaster/gists{/gist_id}","starred_url":"https://api.github.com/users/natemcmaster/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/natemcmaster/subscriptions","organizations_url":"https://api.github.com/users/natemcmaster/orgs","repos_url":"https://api.github.com/users/natemcmaster/repos","events_url":"https://api.github.com/users/natemcmaster/events{/privacy}","received_events_url":"https://api.github.com/users/natemcmaster/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/aspnet/EntityFramework/labels/investigation-needed","name":"investigation-needed","color":"0052cc"},{"url":"https://api.github.com/repos/aspnet/EntityFramework/labels/pri0","name":"pri0","color":"e11d21"}],"state":"open","locked":false,"assignee":{"login":"natemcmaster","id":2696087,"avatar_url":"https://avatars.githubusercontent.com/u/2696087?v=3","gravatar_id":"","url":"https://api.github.com/users/natemcmaster","html_url":"https://github.com/natemcmaster","followers_url":"https://api.github.com/users/natemcmaster/followers","following_url":"https://api.github.com/users/natemcmaster/following{/other_user}","gists_url":"https://api.github.com/users/natemcmaster/gists{/gist_id}","starred_url":"https://api.github.com/users/natemcmaster/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/natemcmaster/subscriptions","organizations_url":"https://api.github.com/users/natemcmaster/orgs","repos_url":"https://api.github.com/users/natemcmaster/repos","events_url":"https://api.github.com/users/natemcmaster/events{/privacy}","received_events_url":"https://api.github.com/users/natemcmaster/received_events","type":"User","site_admin":false},"milestone":{"url":"https://api.github.com/repos/aspnet/EntityFramework/milestones/7","html_url":"https://github.com/aspnet/EntityFramework/milestones/1.0.0","labels_url":"https://api.github.com/repos/aspnet/EntityFramework/milestones/7/labels","id":666128,"number":7,"title":"1.0.0","description":"","creator":{"login":"rowanmiller","id":4741851,"avatar_url":"https://avatars.githubusercontent.com/u/4741851?v=3","gravatar_id":"","url":"https://api.github.com/users/rowanmiller","html_url":"https://github.com/rowanmiller","followers_url":"https://api.github.com/users/rowanmiller/followers","following_url":"https://api.github.com/users/rowanmiller/following{/other_user}","gists_url":"https://api.github.com/users/rowanmiller/gists{/gist_id}","starred_url":"https://api.github.com/users/rowanmiller/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/rowanmiller/subscriptions","organizations_url":"https://api.github.com/users/rowanmiller/orgs","repos_url":"https://api.github.com/users/rowanmiller/repos","events_url":"https://api.github.com/users/rowanmiller/events{/privacy}","received_events_url":"https://api.github.com/users/rowanmiller/received_events","type":"User","site_admin":false},"open_issues":84,"closed_issues":197,"state":"open","created_at":"2014-05-21T19:25:32Z","updated_at":"2016-05-19T16:40:41Z","due_on":null,"closed_at":null},"comments":1,"created_at":"2016-05-02T18:56:10Z","updated_at":"2016-05-19T19:47:23Z","closed_at":null,"body":"The test re-enabled in https://github.com/aspnet/EntityFramework/pull/5062 fails on Linux consistently. We should investigate if this is a bug in SqlClient or in our test setup.\r\n\r\n```\r\nCan_use_sequence_end_to_end_from_multiple_contexts_concurrently_async\r\n```"},"comment":{"url":"https://api.github.com/repos/aspnet/EntityFramework/issues/comments/220432284","html_url":"https://github.com/aspnet/EntityFramework/issues/5254#issuecomment-220432284","issue_url":"https://api.github.com/repos/aspnet/EntityFramework/issues/5254","id":220432284,"user":{"login":"natemcmaster","id":2696087,"avatar_url":"https://avatars.githubusercontent.com/u/2696087?v=3","gravatar_id":"","url":"https://api.github.com/users/natemcmaster","html_url":"https://github.com/natemcmaster","followers_url":"https://api.github.com/users/natemcmaster/followers","following_url":"https://api.github.com/users/natemcmaster/following{/other_user}","gists_url":"https://api.github.com/users/natemcmaster/gists{/gist_id}","starred_url":"https://api.github.com/users/natemcmaster/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/natemcmaster/subscriptions","organizations_url":"https://api.github.com/users/natemcmaster/orgs","repos_url":"https://api.github.com/users/natemcmaster/repos","events_url":"https://api.github.com/users/natemcmaster/events{/privacy}","received_events_url":"https://api.github.com/users/natemcmaster/received_events","type":"User","site_admin":false},"created_at":"2016-05-19T19:47:23Z","updated_at":"2016-05-19T19:47:23Z","body":"This may be an issue in SqlClient connection pooling on Linux.\r\n\r\nTest setup:\r\n50 tasks created. Each task opens a connection to SQL Server to request the next sequence value for 20 items. Tasks run concurrently. On Windows, .NET Core and .NET Framework, this test always passes just fine. On Linux, this test is flaky. It fails about 50% of the time on our CI server:\r\n```\r\nSystem.Data.SqlClient.SqlException : A network-related or instance-specific error occurred while\r\n establishing a connection to SQL Server. The server was not found or was not accessible. Verify \r\nthat the instance name is correct and that SQL Server is configured to allow remote connections. \r\n(provider: TCP Provider, error: 40 - Could not open a connection to SQL Server)\r\n```\r\n\r\nHere is the log output for Linux and Windows. Log output represents actual order of execution. Each line identified with the task number.\r\n\r\n[Windows_log.txt](https://github.com/aspnet/EntityFramework/files/273352/Windows_log.txt)\r\n[Linux_log.txt](https://github.com/aspnet/EntityFramework/files/273351/Linux_log.txt)\r\n\r\n\r\nAs you can see in the Windows log, EF only opens about 12 connections at a time. It appears pooling is kicking it to prevent overwhelming the server. \r\n\r\nIn the Linux log, EF tries to open hundreds of connections without waiting for currently open connections to close.\r\n\r\ncc @saurabh500 are there known issues with SqlClient connection pooling on Linux?"}}