Investigate the cause of flakiness in the WebSocket upgrade code path: Test: http/tests/websocket/tests/hybi/upgrade-simple-ws.html The test is a flaky failure on El Capitan and iOS simulator. It is failing and crashing on Windows. Recent failure: <https://build.webkit.org/builders/Apple%20El%20Capitan%20Debug%20WK1%20(Tests)/builds/5721> Flakiness dashboard: <https://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=http%2Ftests%2Fwebsocket%2Ftests%2Fhybi%2Fupgrade-simple-ws.html> --- /Volumes/Data/slave/ios-simulator-9-release-tests-wk2/build/layout-test-results/http/tests/websocket/tests/hybi/upgrade-simple-ws-expected.txt +++ /Volumes/Data/slave/ios-simulator-9-release-tests-wk2/build/layout-test-results/http/tests/websocket/tests/hybi/upgrade-simple-ws-actual.txt @@ -4,8 +4,4 @@ Created a socket to 'wss://127.0.0.1:9323/websocket/tests/hybi/simple'; readyState 0. The 'ws' protocol should be upgraded to 'wss'. If this happens, we will connect properly and the test will succeed. -Connected; readyState 1 -Resolved URL: wss://127.0.0.1:9323/websocket/tests/hybi/simple -Received: 'Hello from Simple WSH.'; readyState 1 -Closed; readyState 3.
About 1 in 1000 times I can get the test to time out, but I'm not seeing other failures. Since this test relies on an external Python server to do its work, we might be running into some flakiness with that dependency.
Will it reproduce when forced to run many copies of itself in parallel?
This seems to be skipped for all platform: https://searchfox.org/wubkat/rev/6ab17cf692e2176ae76cd00a44e48fb608faaf46/LayoutTests/TestExpectations#2536 Should we try to reenable it and run it again since AppleWin port is gone? or at least enable it for the platform where it is working?
Good idea! If you post a PR and modify the test in some minor way, stress test EWS should execute it with multiple iterations.
Just for an update, I tried this in PR and it seems that this test definitely fails across all platform - https://github.com/WebKit/WebKit/pull/21887