Filed by: rmaries [at] mozilla.com
Parsed log: https://treeherder.mozilla.org/logviewer.html#?job_id=297154008&repo=autoland
Full log: https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/cMW4zHyIQvuaqyOkDW0C2Q/runs/0/artifacts/public/logs/live_backing.log
Reftest URL: https://hg.mozilla.org/mozilla-central/raw-file/tip/layout/tools/reftest/reftest-analyzer.xhtml#logurl=https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/cMW4zHyIQvuaqyOkDW0C2Q/runs/0/artifacts/public/logs/live_backing.log&only_show_unexpected=1

[task 2020-04-10T15:24:23.350Z] 15:24:23 INFO - REFTEST TEST-START | layout/reftests/selection/splitText-normalize.html == layout/reftests/selection/splitText-normalize-ref.html
[task 2020-04-10T15:25:09.783Z] 15:25:09 INFO - [Child 16874, Main Thread] WARNING: could not set real-time limit at process startup: file /builds/worker/checkouts/gecko/dom/ipc/ContentChild.cpp, line 1678
[task 2020-04-10T15:25:10.004Z] 15:25:10 INFO - [Child 16883, Main Thread] WARNING: could not set real-time limit at process startup: file /builds/worker/checkouts/gecko/dom/ipc/ContentChild.cpp, line 1678
[task 2020-04-10T15:25:10.080Z] 15:25:10 INFO - Maximum number of clients reachedAssertion failure: mCompositorDisplay (Failed to create compositor display!), at /builds/worker/checkouts/gecko/gfx/thebes/gfxPlatformGtk.cpp:100
[task 2020-04-10T15:25:10.232Z] 15:25:10 INFO - Initializing stack-fixing for the first stack frame, this may take a while...
[task 2020-04-10T15:25:42.746Z] 15:25:42 INFO - #01: gfxPlatform::Init() [hg:hg.mozilla.org/integration/autoland:gfx/thebes/gfxPlatform.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:1010]
[task 2020-04-10T15:25:42.747Z] 15:25:42 INFO - #02: gfxPlatform::InitChild(mozilla::gfx::ContentDeviceData const&) [hg:hg.mozilla.org/integration/autoland:gfx/thebes/gfxPlatform.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:523]
[task 2020-04-10T15:25:42.753Z] 15:25:42 INFO - #03: mozilla::dom::ContentChild::RecvSetXPCOMProcessAttributes(mozilla::dom::XPCOMInitData const&, mozilla::dom::ipc::StructuredCloneData const&, nsTArray<LookAndFeelInt>&&, nsTArray<mozilla::dom::SystemFontListEntry>&&, mozilla::Maybe<base::FileDescriptor> const&, unsigned long const&) [hg:hg.mozilla.org/integration/autoland:dom/ipc/ContentChild.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:632]
[task 2020-04-10T15:25:42.753Z] 15:25:42 INFO - #04: mozilla::dom::PContentChild::OnMessageReceived(IPC::Message const&) [s3:gecko-generated-sources:fc833f85c9eb05f0c972a253052a05d2f533c620501ec4e74eec0858ef2ef0ed1adc3f90f7c435d98e56c69be82aac82a9d55a2c296121793434084d22edb33f/ipc/ipdl/PContentChild.cpp::10861]
[task 2020-04-10T15:25:42.754Z] 15:25:42 INFO - #05: mozilla::ipc::MessageChannel::DispatchAsyncMessage(mozilla::ipc::ActorLifecycleProxy*, IPC::Message const&) [hg:hg.mozilla.org/integration/autoland:ipc/glue/MessageChannel.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:2188]
[task 2020-04-10T15:25:42.755Z] 15:25:42 INFO - #06: mozilla::ipc::MessageChannel::DispatchMessage(IPC::Message&&) [hg:hg.mozilla.org/integration/autoland:ipc/glue/MessageChannel.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:2114]
[task 2020-04-10T15:25:42.755Z] 15:25:42 INFO - #07: mozilla::ipc::MessageChannel::RunMessage(mozilla::ipc::MessageChannel::MessageTask&) [hg:hg.mozilla.org/integration/autoland:ipc/glue/MessageChannel.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:0]
[task 2020-04-10T15:25:42.756Z] 15:25:42 INFO - #08: mozilla::ipc::MessageChannel::MessageTask::Run() [hg:hg.mozilla.org/integration/autoland:ipc/glue/MessageChannel.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:1992]
[task 2020-04-10T15:25:42.757Z] 15:25:42 INFO - #09: nsThread::ProcessNextEvent(bool, bool*) [hg:hg.mozilla.org/integration/autoland:xpcom/threads/nsThread.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:1200]
[task 2020-04-10T15:25:42.758Z] 15:25:42 INFO - #10: NS_ProcessNextEvent(nsIThread*, bool) [hg:hg.mozilla.org/integration/autoland:xpcom/threads/nsThreadUtils.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:481]
[task 2020-04-10T15:25:42.759Z] 15:25:42 INFO - #11: mozilla::ipc::MessagePump::Run(base::MessagePump::Delegate*) [hg:hg.mozilla.org/integration/autoland:ipc/glue/MessagePump.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:0]
[task 2020-04-10T15:25:42.760Z] 15:25:42 INFO - #12: MessageLoop::RunInternal() [hg:hg.mozilla.org/integration/autoland:ipc/chromium/src/base/message_loop.cc:b3f620eef719eaf7dbf753cc2df911c4edf03f19:315]
[task 2020-04-10T15:25:42.761Z] 15:25:42 INFO - #13: MessageLoop::Run() [hg:hg.mozilla.org/integration/autoland:ipc/chromium/src/base/message_loop.cc:b3f620eef719eaf7dbf753cc2df911c4edf03f19:291]
[task 2020-04-10T15:25:42.762Z] 15:25:42 INFO - #14: nsBaseAppShell::Run() [hg:hg.mozilla.org/integration/autoland:widget/nsBaseAppShell.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:139]
[task 2020-04-10T15:25:42.763Z] 15:25:42 INFO - #15: XRE_RunAppShell() [hg:hg.mozilla.org/integration/autoland:toolkit/xre/nsEmbedFunctions.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:909]
[task 2020-04-10T15:25:42.764Z] 15:25:42 INFO - #16: mozilla::ipc::MessagePumpForChildProcess::Run(base::MessagePump::Delegate*) [hg:hg.mozilla.org/integration/autoland:ipc/glue/MessagePump.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:237]
[task 2020-04-10T15:25:42.764Z] 15:25:42 INFO - #17: MessageLoop::RunInternal() [hg:hg.mozilla.org/integration/autoland:ipc/chromium/src/base/message_loop.cc:b3f620eef719eaf7dbf753cc2df911c4edf03f19:315]
[task 2020-04-10T15:25:42.765Z] 15:25:42 INFO - #18: MessageLoop::Run() [hg:hg.mozilla.org/integration/autoland:ipc/chromium/src/base/message_loop.cc:b3f620eef719eaf7dbf753cc2df911c4edf03f19:291]
[task 2020-04-10T15:25:42.766Z] 15:25:42 INFO - #19: XRE_InitChildProcess(int, char**, XREChildData const*) [hg:hg.mozilla.org/integration/autoland:toolkit/xre/nsEmbedFunctions.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:740]
[task 2020-04-10T15:25:42.828Z] 15:25:42 INFO - #20: content_process_main(mozilla::Bootstrap*, int, char**) [hg:hg.mozilla.org/integration/autoland:ipc/contentproc/plugin-container.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:57]
[task 2020-04-10T15:25:42.829Z] 15:25:42 INFO - #21: main [hg:hg.mozilla.org/integration/autoland:browser/app/nsBrowserApp.cpp:b3f620eef719eaf7dbf753cc2df911c4edf03f19:303]
[task 2020-04-10T15:25:42.830Z] 15:25:42 INFO - fix-stacks error: failed to read breakpad symbols dir /builds/worker/workspace/build/symbols/libc.so.6 for /lib/x86_64-linux-gnu/libc.so.6
[task 2020-04-10T15:25:42.831Z] 15:25:42 INFO - fix-stacks note: this is expected and harmless for system libraries on debug automation runs
[task 2020-04-10T15:25:42.831Z] 15:25:42 INFO - #22: __libc_start_main [/lib/x86_64-linux-gnu/libc.so.6 + 0x21b97]
[task 2020-04-10T15:25:42.835Z] 15:25:42 INFO - #23: ??? [/builds/worker/workspace/build/application/firefox/firefox-bin + 0xfa89]

R/B https://treeherder.mozilla.org/#/jobs?repo=autoland&group_state=expanded&searchStr=linux%2C18.04%2Cx64%2Cquantumrender%2Cdebug%2Creftests%2Cwith%2Cfission%2Cenabled%2Ctest-linux1804-64-qr%2Fdebug-reftest-fis-e10s-6%2Cr-fis%28r6%29&tochange=0d461e1746403eb791ee5d3069dd5ea81a301eb0&fromchange=7502fc7d616a153f13516aafaa33acdb621222d2&selectedJob=296925801

https://wiki.mozilla.org/Bug_Triage#Intermittent_Test_Failure_Cleanup
For more information, please visit auto_nag documentation.

New occurrence: https://treeherder.mozilla.org/logviewer.html#?job_id=304889988&repo=try

https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=305072819&repo=mozilla-central&lineNumber=10849

The recent failures started when the mochitest cross-origin variant got turned on in bug 1647720. Unfortunately, it doesn't fail always at the same test.

(In reply to Sebastian Hengst [:aryx] (needinfo on intermittent or backout) from comment #11)

The recent failures started when the mochitest cross-origin variant got turned on in bug 1647720. Unfortunately, it doesn't fail always at the same test.

I assume, it is just a coincidence. There seem to be a leak of X (window) handles in the test environment on linux. I would not expect this to have much relevance for real life usage of Firefox, though. Edwin, what do you think?

Failures here got classified with bug 1645828, Jens can you assign someone to take a look?

There are 15 failures in the last 7 days on linux1804-64 debug.

Recent failure log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=314424152&repo=mozilla-central&lineNumber=11497

[task 2020-08-30T23:27:35.731Z] 23:27:35 INFO - TEST-START | http://mochi.test:8888/tests/dom/tests/mochitest/dom-level1-core/test_hc_nodeelementnodetype.html
[task 2020-08-30T23:27:35.917Z] 23:27:35 INFO - GECKO(5440) | [Child 13893, Main Thread] WARNING: Extra shutdown CC: 'i < NORMAL_SHUTDOWN_COLLECTIONS', file /builds/worker/checkouts/gecko/xpcom/base/nsCycleCollector.cpp, line 3359
[task 2020-08-30T23:27:35.965Z] 23:27:35 INFO - GECKO(5440) | [Child 13893, Main Thread] WARNING: NS_ENSURE_TRUE(Preferences::InitStaticMembers()) failed: file /builds/worker/checkouts/gecko/modules/libpref/Preferences.cpp, line 4286
[task 2020-08-30T23:27:36.024Z] 23:27:36 INFO - GECKO(5440) | [14001, Unnamed thread 7f009c25d5e0] WARNING: XPCOM objects created/destroyed from static ctor/dtor: file /builds/worker/checkouts/gecko/xpcom/base/nsTraceRefcnt.cpp, line 202
[task 2020-08-30T23:27:36.025Z] 23:27:36 INFO - GECKO(5440) | ### XPCOM_MEM_BLOAT_LOG defined -- logging bloat/leaks to /tmp/tmpvVVMhp.mozrunner/runtests_leaks.log
[task 2020-08-30T23:27:36.026Z] 23:27:36 INFO - GECKO(5440) | [14001, Unnamed thread 7f009c25d5e0] WARNING: XPCOM objects created/destroyed from static ctor/dtor: file /builds/worker/checkouts/gecko/xpcom/base/nsTraceRefcnt.cpp, line 202
[task 2020-08-30T23:27:36.027Z] 23:27:36 INFO - GECKO(5440) | [14001, Main Thread] WARNING: XPCOM_MEM_BLOAT_LOG is set, disabling native allocations.: file /builds/worker/checkouts/gecko/tools/profiler/core/platform.cpp, line 246
[task 2020-08-30T23:27:36.028Z] 23:27:36 INFO - GECKO(5440) | Maximum number of clients reachedUnable to init server: Could not connect: Connection refused
[task 2020-08-30T23:27:36.028Z] 23:27:36 INFO - GECKO(5440) | (/builds/worker/workspace/build/application/firefox/firefox-bin:14001): Gtk-WARNING **: 23:27:36.016: cannot open display: :0
[task 2020-08-30T23:27:36.029Z] 23:27:36 INFO - GECKO(5440) | nsStringStats
[task 2020-08-30T23:27:36.029Z] 23:27:36 INFO - GECKO(5440) | => mAllocCount: 169
[task 2020-08-30T23:27:36.030Z] 23:27:36 INFO - GECKO(5440) | => mReallocCount: 0
[task 2020-08-30T23:27:36.031Z] 23:27:36 INFO - GECKO(5440) | => mFreeCount: 8 -- LEAKED 161 !!!
[task 2020-08-30T23:27:36.031Z] 23:27:36 INFO - GECKO(5440) | => mShareCount: 352
[task 2020-08-30T23:27:36.032Z] 23:27:36 INFO - GECKO(5440) | => mAdoptCount: 0
[task 2020-08-30T23:27:36.032Z] 23:27:36 INFO - GECKO(5440) | => mAdoptFreeCount: 0
[task 2020-08-30T23:27:36.032Z] 23:27:36 INFO - GECKO(5440) | => Process ID: 14001, Thread ID: 139640620722048
[task 2020-08-30T23:27:36.053Z] 23:27:36 INFO - GECKO(5440) | [Parent 5440, Gecko_IOThread] WARNING: FileDescriptorSet destroyed with unconsumed descriptors: file /builds/worker/checkouts/gecko/ipc/chromium/src/chrome/common/file_descriptor_set_posix.cc, line 19
[task 2020-08-30T23:27:36.053Z] 23:27:36 INFO - GECKO(5440) | [Parent 5440, Gecko_IOThread] WARNING: FileDescriptorSet destroyed with unconsumed descriptors: file /builds/worker/checkouts/gecko/ipc/chromium/src/chrome/common/file_descriptor_set_posix.cc, line 19
[task 2020-08-30T23:27:36.053Z] 23:27:36 INFO - GECKO(5440) | [Parent 5440, Gecko_IOThread] WARNING: FileDescriptorSet destroyed with unconsumed descriptors: file /builds/worker/checkouts/gecko/ipc/chromium/src/chrome/common/file_descriptor_set_posix.cc, line 19
[task 2020-08-30T23:27:36.054Z] 23:27:36 INFO - GECKO(5440) | [Parent 5440, Gecko_IOThread] WARNING: FileDescriptorSet destroyed with unconsumed descriptors: file /builds/worker/checkouts/gecko/ipc/chromium/src/chrome/common/file_descriptor_set_posix.cc, line 19
[task 2020-08-30T23:27:36.055Z] 23:27:36 INFO - GECKO(5440) | [Parent 5440, Gecko_IOThread] WARNING: FileDescriptorSet destroyed with unconsumed descriptors: file /builds/worker/checkouts/gecko/ipc/chromium/src/chrome/common/file_descriptor_set_posix.cc, line 19
[task 2020-08-30T23:27:36.056Z] 23:27:36 INFO - GECKO(5440) | [Parent 5440, Gecko_IOThread] WARNING: FileDescriptorSet destroyed with unconsumed descriptors: file /builds/worker/checkouts/gecko/ipc/chromium/src/chrome/common/file_descriptor_set_posix.cc, line 19
[task 2020-08-30T23:27:36.057Z] 23:27:36 INFO - GECKO(5440) | [Parent 5440, Main Thread] WARNING: content process pid = 14001 crashed without leaving a minidump behind: file /builds/worker/checkouts/gecko/dom/ipc/ContentParent.cpp, line 3701
[task 2020-08-30T23:27:36.061Z] 23:27:36 ERROR - GECKO(5440) | A content process crashed and MOZ_CRASHREPORTER_SHUTDOWN is set, shutting down
[task 2020-08-30T23:27:36.390Z] 23:27:36 INFO - GECKO(5440) | [Parent 5440, URL Classifier] WARNING: 'NS_FAILED(rv)', file /builds/worker/checkouts/gecko/netwerk/url-classifier/AsyncUrlChannelClassifier.cpp, line 250
[task 2020-08-30T23:27:36.390Z] 23:27:36 INFO - GECKO(5440) | [Parent 5440, URL Classifier] WARNING: 'NS_FAILED(rv)', file /builds/worker/checkouts/gecko/netwerk/url-classifier/AsyncUrlChannelClassifier.cpp, line 250

[task 2020-08-30T23:27:36.423Z] 23:27:36 INFO - GECKO(5440) | [Parent 5440, URL Classifier] WARNING: 'NS_FAILED(rv)', file /builds/worker/checkouts/gecko/netwerk/url-classifier/AsyncUrlChannelClassifier.cpp, line 250
[task 2020-08-30T23:27:36.423Z] 23:27:36 INFO - GECKO(5440) | [Parent 5440, URL Classifier] WARNING: 'NS_FAILED(rv)', file /builds/worker/checkouts/gecko/netwerk/url-classifier/AsyncUrlChannelClassifier.cpp, line 250
[task 2020-08-30T23:27:36.424Z] 23:27:36 INFO - GECKO(5440) | [Parent 5440, URL Classifier] WARNING: 'NS_FAILED(rv)', file /builds/worker/checkouts/gecko/netwerk/url-classifier/AsyncUrlChannelClassifier.cpp, line 250
[task 2020-08-30T23:27:36.489Z] 23:27:36 INFO - GECKO(5440) | [Parent 5440, Main Thread] WARNING: Received load event on unbridged BrowserParent!: file /builds/worker/checkouts/gecko/dom/ipc/BrowserParent.cpp, line 3968
[task 2020-08-30T23:27:36.489Z] 23:27:36 INFO - GECKO(5440) | [Parent 5440, Main Thread] WARNING: Received load event on unbridged BrowserParent!: file /builds/worker/checkouts/gecko/dom/ipc/BrowserParent.cpp, line 3968
[task 2020-08-30T23:27:36.489Z] 23:27:36 INFO - GECKO(5440) | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-08-30T23:27:36.504Z] 23:27:36 INFO - GECKO(5440) | [Child 13920, Main Thread] WARNING: NS_ENSURE_TRUE(window) failed: file /builds/worker/checkouts/gecko/dom/script/ScriptLoader.cpp, line 1344
[task 2020-08-30T23:27:36.505Z] 23:27:36 INFO - GECKO(5440) | [Child 13920, Main Thread] WARNING: NS_ENSURE_TRUE(window) failed: file /builds/worker/checkouts/gecko/dom/script/ScriptLoader.cpp, line 1344
[task 2020-08-30T23:27:36.525Z] 23:27:36 INFO - GECKO(5440) | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-08-30T23:27:36.585Z] 23:27:36 INFO - GECKO(5440) | [Parent 5440, Main Thread] WARNING: NS_ENSURE_SUCCESS(rv, rv) failed with result 0x80040111 (NS_ERROR_NOT_AVAILABLE): file /builds/worker/checkouts/gecko/netwerk/cache/nsApplicationCacheService.cpp, line 161
[task 2020-08-30T23:27:36.629Z] 23:27:36 INFO - GECKO(5440) | [2020-08-30T23:27:36Z WARN xulstore::persist] tried to remove key that isn't in the store
[task 2020-08-30T23:27:36.630Z] 23:27:36 INFO - GECKO(5440) | [2020-08-30T23:27:36Z WARN xulstore::persist] tried to remove key that isn't in the store
[task 2020-08-30T23:27:36.725Z] 23:27:36 INFO - GECKO(5440) | [Child 13920, Main Thread] WARNING: Extra shutdown CC: 'i < NORMAL_SHUTDOWN_COLLECTIONS', file /builds/worker/checkouts/gecko/xpcom/base/nsCycleCollector.cpp, line 3359
[task 2020-08-30T23:27:36.746Z] 23:27:36 INFO - GECKO(5440) | [Child 13920, Main Thread] WARNING: NS_ENSURE_TRUE(Preferences::InitStaticMembers()) failed: file /builds/worker/checkouts/gecko/modules/libpref/Preferences.cpp, line 4286
[task 2020-08-30T23:27:36.814Z] 23:27:36 INFO - GECKO(5440) | [Child 5705, Main Thread] WARNING: Extra shutdown CC: 'i < NORMAL_SHUTDOWN_COLLECTIONS', file /builds/worker/checkouts/gecko/xpcom/base/nsCycleCollector.cpp, line 3359
[task 2020-08-30T23:27:36.870Z] 23:27:36 INFO - GECKO(5440) | [Child 5619, Main Thread] WARNING: Extra shutdown CC: 'i < NORMAL_SHUTDOWN_COLLECTIONS', file /builds/worker/checkouts/gecko/xpcom/base/nsCycleCollector.cpp, line 3359
[task 2020-08-30T23:27:36.870Z] 23:27:36 INFO - GECKO(5440) | [Child 5705, Main Thread] WARNING: NS_ENSURE_TRUE(Preferences::InitStaticMembers()) failed: file /builds/worker/checkouts/gecko/modules/libpref/Preferences.cpp, line 4286
[task 2020-08-30T23:27:36.890Z] 23:27:36 INFO - GECKO(5440) | [Child 5619, Main Thread] WARNING: NS_ENSURE_TRUE(Preferences::InitStaticMembers()) failed: file /builds/worker/checkouts/gecko/modules/libpref/Preferences.cpp, line 4286
[task 2020-08-30T23:27:37.361Z] 23:27:37 INFO - GECKO(5440) | [Child 13947, Main Thread] WARNING: Extra shutdown CC: 'i < NORMAL_SHUTDOWN_COLLECTIONS', file /builds/worker/checkouts/gecko/xpcom/base/nsCycleCollector.cpp, line 3359
[task 2020-08-30T23:27:37.361Z] 23:27:37 INFO - GECKO(5440) | [Child 13974, Main Thread] WARNING: Extra shutdown CC: 'i < NORMAL_SHUTDOWN_COLLECTIONS', file /builds/worker/checkouts/gecko/xpcom/base/nsCycleCollector.cpp, line 3359
[task 2020-08-30T23:27:37.402Z] 23:27:37 INFO - GECKO(5440) | [Child 13974, Main Thread] WARNING: NS_ENSURE_TRUE(Preferences::InitStaticMembers()) failed: file /builds/worker/checkouts/gecko/modules/libpref/Preferences.cpp, line 4286
[task 2020-08-30T23:27:37.402Z] 23:27:37 INFO - GECKO(5440) | [Child 13947, Main Thread] WARNING: NS_ENSURE_TRUE(Preferences::InitStaticMembers()) failed: file /builds/worker/checkouts/gecko/modules/libpref/Preferences.cpp, line 4286
[task 2020-08-30T23:27:37.692Z] 23:27:37 INFO - GECKO(5440) | [Child 5682, Main Thread] WARNING: Extra shutdown CC: 'i < NORMAL_SHUTDOWN_COLLECTIONS', file /builds/worker/checkouts/gecko/xpcom/base/nsCycleCollector.cpp, line 3359
[task 2020-08-30T23:27:37.728Z] 23:27:37 INFO - GECKO(5440) | [Child 5682, Main Thread] WARNING: NS_ENSURE_TRUE(Preferences::InitStaticMembers()) failed: file /builds/worker/checkouts/gecko/modules/libpref/Preferences.cpp, line 4286
[task 2020-08-30T23:27:37.926Z] 23:27:37 INFO - GECKO(5440) | 1598830057913 Marionette TRACE Received observer notification xpcom-will-shutdown
[task 2020-08-30T23:27:37.926Z] 23:27:37 INFO - GECKO(5440) | 1598830057913 Marionette INFO Stopped listening on port 2828
[task 2020-08-30T23:27:37.926Z] 23:27:37 INFO - GECKO(5440) | 1598830057913 Marionette DEBUG Marionette stopped listening
[task 2020-08-30T23:27:38.024Z] 23:27:38 INFO - GECKO(5440) | [Parent 5440, Main Thread] WARNING: NS_ENSURE_SUCCESS(rv, rv) failed with result 0x80004005 (NS_ERROR_FAILURE): file /builds/worker/checkouts/gecko/js/xpconnect/loader/mozJSComponentLoader.cpp, line 228
[task 2020-08-30T23:27:38.025Z] 23:27:38 INFO - GECKO(5440) | [Parent 5440, Main Thread] WARNING: NS_ENSURE_SUCCESS(rv, rv) failed with result 0x80004005 (NS_ERROR_FAILURE): file /builds/worker/checkouts/gecko/js/xpconnect/loader/mozJSComponentLoader.cpp, line 256
[task 2020-08-30T23:27:39.267Z] 23:27:39 INFO - GECKO(5440) | [Parent 5440, Main Thread] WARNING: Extra shutdown CC: 'i < NORMAL_SHUTDOWN_COLLECTIONS', file /builds/worker/checkouts/gecko/xpcom/base/nsCycleCollector.cpp, line 3359
[task 2020-08-30T23:27:39.501Z] 23:27:39 INFO - GECKO(5440) | [Parent 5440, Main Thread] WARNING: NS_ENSURE_TRUE(Preferences::InitStaticMembers()) failed: file /builds/worker/checkouts/gecko/modules/libpref/Preferences.cpp, line 4286
[task 2020-08-30T23:27:39.566Z] 23:27:39 INFO - TEST-INFO | Main app process: exit 0

Bug 1635451 will probably solve this problem, so work should be expected there.

These have a high failure frequency rate, 15 out of 16 runs failed: https://treeherder.mozilla.org/#/jobs?repo=mozilla-central&resultStatus=pending%2Crunning%2Csuccess%2Ctestfailed%2Cbusted%2Cexception&searchStr=Linux%2C18.04%2Cx64%2Cdebug%2CMochitests%2Cwith%2Ccross-origin%2Cand%2Cfission%2Cenabled%2Ctest-linux1804-64%2Fdebug-mochitest-plain-fis-xorig-e10s%2C8&revision=e00579f0f7354760631f6dc8f1d6ba9a31a59b51&selectedTaskRun=D77_2_hNQwGAVxNLTk2sXg.0

They were first classified on this merge https://treeherder.mozilla.org/#/jobs?repo=mozilla-central&selectedTaskRun=TmACxLHTRdmO9NAyKUouRw.0&searchStr=linux%2C18.04%2Cx64%2Cdebug%2Cmochitests%2Cwith%2Ccross-origin%2Cand%2Cfission%2Cenabled%2Ctest-linux1804-64%2Fdebug-mochitest-plain-fis-xorig-e10s%2C3&revision=1415430432706ec6b8c7590cda9b8ca87397e7a7

Real failure rate is now show here as the failures were classified with different bugs ( Bug 1658172, Bug 1655017, Bug 1560096, etc) since they first showed up.

(In reply to Jens Stutte [:jstutte] (REO for FF 81) from comment #16)

There seem to be a leak of X (window) handles in the test environment on linux. I would not expect this to have much relevance for real life usage of Firefox, though.

Are there indications that we're truly leaking connections to the X server (or have live content processes that should have exited), or is this just an artifact of the test suite causing usage patterns that wouldn't happen normally? And is it possible to work around this by increasing the connection limit? (I assume we control the X server config, whether it's Xvfb or using real hardware.)

(In reply to Jed Davis [:jld] ⟨⏰|UTC-6⟩ ⟦he/him⟧ from comment #23)

And is it possible to work around this by increasing the connection limit? (I assume we control the X server config, whether it's Xvfb or using real hardware.)

So we did that in bug 1638183, setting it to 2048. (As for Xvfb, I was wondering if the failing runs might have been using it instead of the normal X server, because it probably doesn't read all of the normal config files by default. But the code that runs it sends its output/error to an xvfb.log artifact, which exists in a failing run but is empty, and the Maximum number of clients reached (which I assume is from the X server) goes to the main log file. So that may not be relevant.)

But… the latest failing run in comment #22 has 582 launched child process lines, so even if all of those processes were alive at the same time (which is questionable), and each one has 2 connections to the X server (the normal number is 1, but see bug 1635451 comment #2), that wouldn't add up to 2048. Which suggests that either the config change isn't working, or there's a real leak of X server connections (which normally is very unlikely, but we're doing enough unusual things with graphics that it's not out of the question).

The summary (title) of this bug is incorrect. The assertion cannot be triggered because the code has been removed in bug 1657315 .

The following error:

Maximum number of clients reachedUnable to init server: Could not connect: Connection refused

... seems to already be tracked at bug 1658172.

(In reply to Jed Davis [:jld] ⟨⏰|UTC-6⟩ ⟦he/him⟧ from comment #24)

and each one has 2 connections to the X server

This is false now (and has been for the past month), thanks to bug 1657315; I observe only 1 connection per content process.

(In reply to Rob Wu [:robwu] from comment #25)

The summary (title) of this bug is incorrect. The assertion cannot be triggered because the code has been removed in bug 1657315 .

The following error:

Maximum number of clients reachedUnable to init server: Could not connect: Connection refused

... seems to already be tracked at bug 1658172.

Can we close as a duplicate?

(In reply to Andreea Pavel [:apavel] from comment #28)

(In reply to Rob Wu [:robwu] from comment #25)

The summary (title) of this bug is incorrect. The assertion cannot be triggered because the code has been removed in bug 1657315 .

The following error:

Maximum number of clients reachedUnable to init server: Could not connect: Connection refused

... seems to already be tracked at bug 1658172.

Can we close as a duplicate?

I'd say yes. Although actually fixed by bug 1657315, I suggest to mark it as a duplicate of bug 1658172 since some failures are still (incorrectly) attributed to this bug.