Bug: Intermittent browser/base/content/test/performance/browser_startup_mainthreadio.js | no main thread IO when we expected some during before opening first browser window: C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner (ProfD:) -
Status: RESOLVED
Priority: P5
Resolution: DUPLICATE
Created: 2021-09-01 04:21:44+00:00
Resolved: 2022-08-15 12:17:57+00:00

**Filed by:** malexandru [at] mozilla.com
**Parsed log:** https://treeherder.mozilla.org/logviewer?job_id=350128269&repo=autoland
**Full log:** https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/Ubms1mYnR3uah7mdTPYamw/runs/0/artifacts/public/logs/live_backing.log

---
```
[task 2021-09-01T02:51:11.793Z] 02:51:11     INFO - TEST-START | browser/base/content/test/performance/browser_startup_mainthreadio.js
[task 2021-09-01T02:51:11.837Z] 02:51:11     INFO - TEST-INFO | started process screenshot
[task 2021-09-01T02:51:11.908Z] 02:51:11     INFO - TEST-INFO | screenshot: exit 0
[task 2021-09-01T02:51:11.915Z] 02:51:11     INFO - Buffered messages logged at 02:51:11
[task 2021-09-01T02:51:11.915Z] 02:51:11     INFO - Entering test bound 
[task 2021-09-01T02:51:11.916Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | The IO interposer should be enabled in builds that are not RELEASE_OR_BETA - 
[task 2021-09-01T02:51:11.920Z] 02:51:11     INFO - known main thread IO paths during before profile selection:
[task 2021-09-01T02:51:11.920Z] 02:51:11     INFO -   Z:\task_163046331524447\AppData\Roaming\Mozilla\Firefox\Crash Reports\InstallTime20* - condition: true, stat: 1, read: 1, write: 2, close: 1, listedPath: UAppData:Crash Reports/InstallTime20*
[task 2021-09-01T02:51:11.920Z] 02:51:11     INFO -   Z:\task_163046331524447\AppData\Roaming\Mozilla\Firefox\Crash Reports\LastCrash - condition: true, stat: 1, read: 1, listedPath: UAppData:Crash Reports/LastCrash
[task 2021-09-01T02:51:11.920Z] 02:51:11     INFO -   Z:\task_163046331524447\AppData\Roaming\Mozilla\Firefox\profiles.ini - condition: true, ignoreIfUnused: true, read: 1, stat: 1, listedPath: UAppData:profiles.ini
[task 2021-09-01T02:51:11.920Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner - condition: true, stat: 1, listedPath: ProfD:
[task 2021-09-01T02:51:11.920Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\compatibility.ini - write: 18, close: 1, listedPath: ProfLD:compatibility.ini
[task 2021-09-01T02:51:11.920Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\parent.lock - condition: true, stat: 1, listedPath: ProfD:parent.lock
[task 2021-09-01T02:51:11.920Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\minidumps - condition: true, stat: 1, listedPath: ProfD:minidumps
[task 2021-09-01T02:51:11.920Z] 02:51:11     INFO -   Z:\task_163046331524447\build\application\firefox\browser\defaults\preferences - condition: true, stat: 1, listedPath: XCurProcD:defaults/preferences
[task 2021-09-01T02:51:11.920Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\startupCache\scriptCache-child-current.bin - condition: true, stat: 1, listedPath: ProfLDS:startupCache/scriptCache-child-current.bin
[task 2021-09-01T02:51:11.920Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\startupCache\scriptCache-child.bin - condition: true, stat: 1, listedPath: ProfLDS:startupCache/scriptCache-child.bin
[task 2021-09-01T02:51:11.921Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\startupCache\scriptCache-current.bin - condition: true, stat: 1, listedPath: ProfLDS:startupCache/scriptCache-current.bin
[task 2021-09-01T02:51:11.921Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\startupCache\scriptCache.bin - condition: true, stat: 1, listedPath: ProfLDS:startupCache/scriptCache.bin
[task 2021-09-01T02:51:11.921Z] 02:51:11     INFO -   Z:\task_163046331524447\build\application\firefox\defaults\pref\channel-prefs.js - stat: 1, read: 1, close: 1, listedPath: PrfDef:channel-prefs.js
[task 2021-09-01T02:51:11.921Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\prefs.js - stat: 1, read: 1, close: 1, listedPath: PrefD:prefs.js
[task 2021-09-01T02:51:11.921Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\user.js - stat: 1, read: 1, close: 1, listedPath: PrefD:user.js
[task 2021-09-01T02:51:11.921Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\xulstore\data.mdb - condition: true, read: 1, write: 1, listedPath: ProfD:xulstore/data.mdb
[task 2021-09-01T02:51:11.921Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\AppData\Roaming\Mozilla\Firefox\Crash Reports\InstallTime20210901010303
[task 2021-09-01T02:51:11.922Z] 02:51:11     INFO - (PoisonIOInterposer) read - Z:\task_163046331524447\AppData\Roaming\Mozilla\Firefox\Crash Reports\InstallTime20210901010303
[task 2021-09-01T02:51:11.923Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\AppData\Roaming\Mozilla\Firefox\Crash Reports\LastCrash
[task 2021-09-01T02:51:11.923Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\AppData\Roaming\Mozilla\Firefox\profiles.ini
[task 2021-09-01T02:51:11.924Z] 02:51:11     INFO - (PoisonIOInterposer) stat - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner
[task 2021-09-01T02:51:11.924Z] 02:51:11     INFO - (PoisonIOInterposer) stat - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\parent.lock
[task 2021-09-01T02:51:11.925Z] 02:51:11     INFO - (PoisonIOInterposer) stat - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\minidumps
[task 2021-09-01T02:51:11.925Z] 02:51:11     INFO - (PoisonIOInterposer) write - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\compatibility.ini
[task 2021-09-01T02:51:11.926Z] 02:51:11     INFO - (PoisonIOInterposer) write - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\compatibility.ini
[task 2021-09-01T02:51:11.926Z] 02:51:11     INFO - (PoisonIOInterposer) write - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\compatibility.ini
[task 2021-09-01T02:51:11.927Z] 02:51:11     INFO - (PoisonIOInterposer) write - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\compatibility.ini
[task 2021-09-01T02:51:11.927Z] 02:51:11     INFO - (PoisonIOInterposer) write - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\compatibility.ini
[task 2021-09-01T02:51:11.928Z] 02:51:11     INFO - (PoisonIOInterposer) write - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\compatibility.ini
[task 2021-09-01T02:51:11.928Z] 02:51:11     INFO - (PoisonIOInterposer) write - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\compatibility.ini
[task 2021-09-01T02:51:11.929Z] 02:51:11     INFO - (PoisonIOInterposer) write - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\compatibility.ini
[task 2021-09-01T02:51:11.929Z] 02:51:11     INFO - (PoisonIOInterposer) write - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\compatibility.ini
[task 2021-09-01T02:51:11.930Z] 02:51:11     INFO - (PoisonIOInterposer) read - Z:\task_163046331524447\build\application\firefox\defaults\pref\channel-prefs.js
[task 2021-09-01T02:51:11.930Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\build\application\firefox\browser\defaults\preferences
[task 2021-09-01T02:51:11.931Z] 02:51:11     INFO - (PoisonIOInterposer) read - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\prefs.js
[task 2021-09-01T02:51:11.931Z] 02:51:11     INFO - (PoisonIOInterposer) read - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\user.js
[task 2021-09-01T02:51:11.932Z] 02:51:11     INFO - (PoisonIOInterposer) stat - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\startupCache\scriptCache-child.bin
[task 2021-09-01T02:51:11.933Z] 02:51:11     INFO - (PoisonIOInterposer) stat - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\startupCache\scriptCache-child-current.bin
[task 2021-09-01T02:51:11.933Z] 02:51:11     INFO - (PoisonIOInterposer) stat - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\startupCache\scriptCache.bin
[task 2021-09-01T02:51:11.934Z] 02:51:11     INFO - (PoisonIOInterposer) stat - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\startupCache\scriptCache-current.bin
[task 2021-09-01T02:51:11.935Z] 02:51:11     INFO - (PoisonIOInterposer) read - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\xulstore\data.mdb
[task 2021-09-01T02:51:11.935Z] 02:51:11     INFO - (PoisonIOInterposer) write - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\xulstore\data.mdb
[task 2021-09-01T02:51:11.936Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | stat on Z:\task_163046331524447\AppData\Roaming\Mozilla\Firefox\Crash Reports\InstallTime20* as many times as expected before profile selection - 
<...>
[task 2021-09-01T02:51:11.959Z] 02:51:11     INFO - known main thread IO paths during before opening first browser window:
[task 2021-09-01T02:51:11.959Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner - condition: true, stat: 1, listedPath: ProfD:
[task 2021-09-01T02:51:11.959Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite-journal - condition: true, stat: 3, write: 4, listedPath: ProfD:cookies.sqlite-journal
[task 2021-09-01T02:51:11.960Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite - condition: true, stat: 2, read: 3, write: 1, listedPath: ProfD:cookies.sqlite
[task 2021-09-01T02:51:11.960Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite-wal - condition: true, stat: 2, listedPath: ProfD:cookies.sqlite-wal
[task 2021-09-01T02:51:11.960Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\extensions - ignoreIfUnused: true, condition: true, stat: 1, listedPath: ProfD:extensions
[task 2021-09-01T02:51:11.960Z] 02:51:11     INFO -   Z:\task_163046331524447\AppData\Roaming\Mozilla\Firefox - ignoreIfUnused: true, condition: true, stat: 1, listedPath: UAppData:
[task 2021-09-01T02:51:11.960Z] 02:51:11     INFO -   Z:\task_163046331524447\build\application\firefox\browser\features\doh-rollout@mozilla.org.xpi - stat: 3, close: 2, listedPath: XREAppFeat:doh-rollout@mozilla.org.xpi
[task 2021-09-01T02:51:11.960Z] 02:51:11     INFO -   Z:\task_163046331524447\build\application\firefox\browser\features\formautofill@mozilla.org.xpi - stat: 3, close: 2, listedPath: XREAppFeat:formautofill@mozilla.org.xpi
[task 2021-09-01T02:51:11.960Z] 02:51:11     INFO -   Z:\task_163046331524447\build\application\firefox\browser\features\pictureinpicture@mozilla.org.xpi - stat: 3, close: 2, listedPath: XREAppFeat:pictureinpicture@mozilla.org.xpi
[task 2021-09-01T02:51:11.960Z] 02:51:11     INFO -   Z:\task_163046331524447\build\application\firefox\browser\features\screenshots@mozilla.org.xpi - stat: 3, close: 2, listedPath: XREAppFeat:screenshots@mozilla.org.xpi
[task 2021-09-01T02:51:11.960Z] 02:51:11     INFO -   Z:\task_163046331524447\build\application\firefox\browser\features\webcompat-reporter@mozilla.org.xpi - stat: 3, close: 2, listedPath: XREAppFeat:webcompat-reporter@mozilla.org.xpi
[task 2021-09-01T02:51:11.960Z] 02:51:11     INFO -   Z:\task_163046331524447\build\application\firefox\browser\features\webcompat@mozilla.org.xpi - stat: 3, close: 2, listedPath: XREAppFeat:webcompat@mozilla.org.xpi
[task 2021-09-01T02:51:11.961Z] 02:51:11     INFO - (PoisonIOInterposer) stat - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\extensions
[task 2021-09-01T02:51:11.961Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\build\application\firefox\browser\features\doh-rollout@mozilla.org.xpi
[task 2021-09-01T02:51:11.962Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\build\application\firefox\browser\features\formautofill@mozilla.org.xpi
[task 2021-09-01T02:51:11.962Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\build\application\firefox\browser\features\pictureinpicture@mozilla.org.xpi
[task 2021-09-01T02:51:11.963Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\build\application\firefox\browser\features\screenshots@mozilla.org.xpi
[task 2021-09-01T02:51:11.964Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\build\application\firefox\browser\features\webcompat-reporter@mozilla.org.xpi
[task 2021-09-01T02:51:11.964Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\build\application\firefox\browser\features\webcompat@mozilla.org.xpi
[task 2021-09-01T02:51:11.965Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\build\application\firefox\browser\features\doh-rollout@mozilla.org.xpi
[task 2021-09-01T02:51:11.965Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\build\application\firefox\browser\features\formautofill@mozilla.org.xpi
[task 2021-09-01T02:51:11.966Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\build\application\firefox\browser\features\pictureinpicture@mozilla.org.xpi
[task 2021-09-01T02:51:11.966Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\build\application\firefox\browser\features\screenshots@mozilla.org.xpi
[task 2021-09-01T02:51:11.967Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\build\application\firefox\browser\features\webcompat-reporter@mozilla.org.xpi
[task 2021-09-01T02:51:11.967Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\build\application\firefox\browser\features\webcompat@mozilla.org.xpi
[task 2021-09-01T02:51:11.968Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | stat on C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner allowed 1 more times before opening first browser window - 
[task 2021-09-01T02:51:11.968Z] 02:51:11     INFO - Buffered messages finished
[task 2021-09-01T02:51:11.969Z] 02:51:11     INFO - TEST-UNEXPECTED-FAIL | browser/base/content/test/performance/browser_startup_mainthreadio.js | no main thread IO when we expected some during before opening first browser window: C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner (ProfD:) - 
[task 2021-09-01T02:51:11.969Z] 02:51:11     INFO - Stack trace:
[task 2021-09-01T02:51:11.970Z] 02:51:11     INFO - chrome://mochikit/content/browser-test.js:test_ok:1336
[task 2021-09-01T02:51:11.970Z] 02:51:11     INFO - chrome://mochitests/content/browser/browser/base/content/test/performance/browser_startup_mainthreadio.js:null:870
[task 2021-09-01T02:51:11.970Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | stat on C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite-journal allowed 3 more times before opening first browser window - 
[task 2021-09-01T02:51:11.971Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | write on C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite-journal allowed 4 more times before opening first browser window - 
[task 2021-09-01T02:51:11.971Z] 02:51:11     INFO - Not taking screenshot here: see the one that was previously logged
[task 2021-09-01T02:51:11.973Z] 02:51:11     INFO - TEST-UNEXPECTED-FAIL | browser/base/content/test/performance/browser_startup_mainthreadio.js | no main thread IO when we expected some during before opening first browser window: C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite-journal (ProfD:cookies.sqlite-journal) - 
[task 2021-09-01T02:51:11.973Z] 02:51:11     INFO - Stack trace:
[task 2021-09-01T02:51:11.973Z] 02:51:11     INFO - chrome://mochikit/content/browser-test.js:test_ok:1336
[task 2021-09-01T02:51:11.973Z] 02:51:11     INFO - chrome://mochitests/content/browser/browser/base/content/test/performance/browser_startup_mainthreadio.js:null:870
[task 2021-09-01T02:51:11.973Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | stat on C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite allowed 2 more times before opening first browser window - 
[task 2021-09-01T02:51:11.974Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | read on C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite allowed 3 more times before opening first browser window - 
[task 2021-09-01T02:51:11.975Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | write on C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite allowed 1 more times before opening first browser window - 
[task 2021-09-01T02:51:11.975Z] 02:51:11     INFO - Not taking screenshot here: see the one that was previously logged
[task 2021-09-01T02:51:11.976Z] 02:51:11     INFO - TEST-UNEXPECTED-FAIL | browser/base/content/test/performance/browser_startup_mainthreadio.js | no main thread IO when we expected some during before opening first browser window: C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite (ProfD:cookies.sqlite) - 
[task 2021-09-01T02:51:11.976Z] 02:51:11     INFO - Stack trace:
[task 2021-09-01T02:51:11.976Z] 02:51:11     INFO - chrome://mochikit/content/browser-test.js:test_ok:1336
[task 2021-09-01T02:51:11.976Z] 02:51:11     INFO - chrome://mochitests/content/browser/browser/base/content/test/performance/browser_startup_mainthreadio.js:null:870
[task 2021-09-01T02:51:11.977Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | stat on C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite-wal allowed 2 more times before opening first browser window - 
[task 2021-09-01T02:51:11.977Z] 02:51:11     INFO - Not taking screenshot here: see the one that was previously logged
[task 2021-09-01T02:51:11.979Z] 02:51:11     INFO - TEST-UNEXPECTED-FAIL | browser/base/content/test/performance/browser_startup_mainthreadio.js | no main thread IO when we expected some during before opening first browser window: C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite-wal (ProfD:cookies.sqlite-wal) - 
[task 2021-09-01T02:51:11.979Z] 02:51:11     INFO - Stack trace:
[task 2021-09-01T02:51:11.979Z] 02:51:11     INFO - chrome://mochikit/content/browser-test.js:test_ok:1336
[task 2021-09-01T02:51:11.979Z] 02:51:11     INFO - chrome://mochitests/content/browser/browser/base/content/test/performance/browser_startup_mainthreadio.js:null:870
[task 2021-09-01T02:51:11.980Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | stat on C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\extensions as many times as expected before opening first browser window - 
[task 2021-09-01T02:51:11.980Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | stat on Z:\task_163046331524447\AppData\Roaming\Mozilla\Firefox allowed 1 more times before opening first browser window - 
[task 2021-09-01T02:51:11.981Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | stat on Z:\task_163046331524447\build\application\firefox\browser\features\doh-rollout@mozilla.org.xpi allowed 1 more times before opening first browser window - 
[task 2021-09-01T02:51:11.982Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | close on Z:\task_163046331524447\build\application\firefox\browser\features\doh-rollout@mozilla.org.xpi allowed 2 more times before opening first browser window - 
[task 2021-09-01T02:51:11.983Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | stat on Z:\task_163046331524447\build\application\firefox\browser\features\formautofill@mozilla.org.xpi allowed 1 more times before opening first browser window - 
[task 2021-09-01T02:51:11.983Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | close on Z:\task_163046331524447\build\application\firefox\browser\features\formautofill@mozilla.org.xpi allowed 2 more times before opening first browser window - 
[task 2021-09-01T02:51:11.984Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | stat on Z:\task_163046331524447\build\application\firefox\browser\features\pictureinpicture@mozilla.org.xpi allowed 1 more times before opening first browser window - 
[task 2021-09-01T02:51:11.985Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | close on Z:\task_163046331524447\build\application\firefox\browser\features\pictureinpicture@mozilla.org.xpi allowed 2 more times before opening first browser window - 
[task 2021-09-01T02:51:11.985Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | stat on Z:\task_163046331524447\build\application\firefox\browser\features\screenshots@mozilla.org.xpi allowed 1 more times before opening first browser window - 
[task 2021-09-01T02:51:11.986Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | close on Z:\task_163046331524447\build\application\firefox\browser\features\screenshots@mozilla.org.xpi allowed 2 more times before opening first browser window - 
[task 2021-09-01T02:51:11.987Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | stat on Z:\task_163046331524447\build\application\firefox\browser\features\webcompat-reporter@mozilla.org.xpi allowed 1 more times before opening first browser window - 
[task 2021-09-01T02:51:11.988Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | close on Z:\task_163046331524447\build\application\firefox\browser\features\webcompat-reporter@mozilla.org.xpi allowed 2 more times before opening first browser window - 
[task 2021-09-01T02:51:11.989Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | stat on Z:\task_163046331524447\build\application\firefox\browser\features\webcompat@mozilla.org.xpi allowed 1 more times before opening first browser window - 
[task 2021-09-01T02:51:11.990Z] 02:51:11     INFO - TEST-PASS | browser/base/content/test/performance/browser_startup_mainthreadio.js | close on Z:\task_163046331524447\build\application\firefox\browser\features\webcompat@mozilla.org.xpi allowed 2 more times before opening first browser window - 
[task 2021-09-01T02:51:11.992Z] 02:51:11     INFO - known main thread IO paths during before first paint:
[task 2021-09-01T02:51:11.992Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Mozilla\updates\D69A426EEFD7468 - condition: true, stat: 1, listedPath: OldUpdRootD:
[task 2021-09-01T02:51:11.992Z] 02:51:11     INFO -   C:\ProgramData\Mozilla\updates\D69A426EEFD7468\updates\0\update.status - condition: true, stat: 1, listedPath: UpdRootD:updates/0/update.status
[task 2021-09-01T02:51:11.992Z] 02:51:11     INFO -   Z:\task_163046331524447\build\application\firefox\distribution\distribution.ini - condition: true, stat: 1, listedPath: XREAppDist:distribution.ini
[task 2021-09-01T02:51:11.992Z] 02:51:11     INFO -   *Fonts\StaticCache.dat - condition: true, ignoreIfUnused: true, read: 1, listedPath: *Fonts/StaticCache.dat
[task 2021-09-01T02:51:11.992Z] 02:51:11     INFO -   C:\Windows\system32\spool\drivers\color\* - condition: true, read: 1, listedPath: SysD:spool/drivers/color/*
[task 2021-09-01T02:51:11.992Z] 02:51:11     INFO -   Z:\task_163046331524447\AppData\Roaming\Mozilla\Firefox - ignoreIfUnused: true, condition: true, stat: 1, listedPath: UAppData:
[task 2021-09-01T02:51:11.992Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\d3d11layers.guard - ignoreIfUnused: true, stat: 1, listedPath: ProfD:d3d11layers.guard
[task 2021-09-01T02:51:11.992Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\glcontext.guard - ignoreIfUnused: true, stat: 1, listedPath: ProfD:glcontext.guard
[task 2021-09-01T02:51:11.992Z] 02:51:11     INFO -   C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\wmfvpxvideo.guard - ignoreIfUnused: true, stat: 1, listedPath: ProfD:wmfvpxvideo.guard
[task 2021-09-01T02:51:11.993Z] 02:51:11     INFO - (PoisonIOInterposer) stat - C:\Users\task_163046331524447\AppData\Local\Mozilla\updates\D69A426EEFD7468
[task 2021-09-01T02:51:11.993Z] 02:51:11     INFO - (PoisonIOInterposer) stat - C:\ProgramData\Mozilla\updates\D69A426EEFD7468\updates\0\update.status
[task 2021-09-01T02:51:11.994Z] 02:51:11     INFO - (PoisonIOInterposer) stat - Z:\task_163046331524447\build\application\firefox\distribution\distribution.ini
[task 2021-09-01T02:51:11.994Z] 02:51:11     INFO - Not taking screenshot here: see the one that was previously logged
[task 2021-09-01T02:51:11.995Z] 02:51:11     INFO - TEST-UNEXPECTED-FAIL | browser/base/content/test/performance/browser_startup_mainthreadio.js | unexpected stat on C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite before first paint - 
[task 2021-09-01T02:51:11.995Z] 02:51:11     INFO - Stack trace:
[task 2021-09-01T02:51:11.995Z] 02:51:11     INFO -   Connection::initialize
[task 2021-09-01T02:51:11.995Z] 02:51:11     INFO -   Task CookiePersistentStorage::InitDBConn
[task 2021-09-01T02:51:11.995Z] 02:51:11     INFO -   XREMain::XRE_main
[task 2021-09-01T02:51:11.996Z] 02:51:11     INFO - (PoisonIOInterposer) stat - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite
[task 2021-09-01T02:51:11.996Z] 02:51:11     INFO - Not taking screenshot here: see the one that was previously logged
[task 2021-09-01T02:51:11.997Z] 02:51:11     INFO - TEST-UNEXPECTED-FAIL | browser/base/content/test/performance/browser_startup_mainthreadio.js | unexpected read on C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite before first paint - 
[task 2021-09-01T02:51:11.997Z] 02:51:11     INFO - Stack trace:
[task 2021-09-01T02:51:11.997Z] 02:51:11     INFO -   Connection::initialize
[task 2021-09-01T02:51:11.997Z] 02:51:11     INFO -   Task CookiePersistentStorage::InitDBConn
[task 2021-09-01T02:51:11.997Z] 02:51:11     INFO -   XREMain::XRE_main
[task 2021-09-01T02:51:11.998Z] 02:51:11     INFO - (PoisonIOInterposer) read - C:\Users\task_163046331524447\AppData\Local\Temp\tmpb5mlgb1a.mozrunner\cookies.sqlite
```