Bug: 62.64 - 6.89% google-mail fcp / bing-search SpeedIndex + 2 more (Linux, OSX, Windows) regression on Tue August 8 2023
Status: RESOLVED
Priority: --
Resolution: WONTFIX
Created: 2023-08-14 08:06:27+00:00
Resolved: 2023-10-05 19:35:24+00:00

Perfherder has detected a browsertime performance regression from push [80fde27f01a774b21528e4955162e350e4ee1f23](https://hg.mozilla.org/integration/autoland/pushloghtml?changeset=80fde27f01a774b21528e4955162e350e4ee1f23). As author of one of the patches included in that push, we need your help to address this regression.

### Regressions:

| **Ratio** | **Test** | **Platform** | **Options** | **Absolute values (old vs new)** |  **Performance Profiles** | 
|--|--|--|--|--|--| 
| [63%](https://treeherder.mozilla.org/perfherder/graphs?timerange=1209600&series=autoland,3776837,1,13)  | [google-mail](https://firefox-source-docs.mozilla.org/testing/perfdocs/raptor.html#google-mail-d) fcp | linux1804-64-shippable-qr | cold fission webrender | [324.42](https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/fV8u_BAqQ2OSCvEdGAIDmg/runs/0/artifacts/public/test_info/browsertime-results.tgz) -> [527.63](https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/B90NOyosQb2yc8koU466NQ/runs/0/artifacts/public/test_info/browsertime-results.tgz) | [Before](https://profiler.firefox.com/from-url/https%3A%2F%2Ffirefox-ci-tc.services.mozilla.com%2Fapi%2Fqueue%2Fv1%2Ftask%2FfV8u_BAqQ2OSCvEdGAIDmg%2Fruns%2F0%2Fartifacts%2Fpublic%2Ftest_info%2Fprofile_google-mail.zip)/[After](https://profiler.firefox.com/from-url/https%3A%2F%2Ffirefox-ci-tc.services.mozilla.com%2Fapi%2Fqueue%2Fv1%2Ftask%2FB90NOyosQb2yc8koU466NQ%2Fruns%2F0%2Fartifacts%2Fpublic%2Ftest_info%2Fprofile_google-mail.zip) |
| [59%](https://treeherder.mozilla.org/perfherder/graphs?timerange=1209600&series=autoland,3777757,1,13)  | [google-mail](https://firefox-source-docs.mozilla.org/testing/perfdocs/raptor.html#google-mail-d) fcp | windows10-64-shippable-qr | cold fission webrender | [242.94](https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/BVv-1FiHRcaYKEIlQi0u5A/runs/0/artifacts/public/test_info/browsertime-results.tgz) -> [385.71](https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/F0S6VX8VSm2Zgz9leDjlcw/runs/0/artifacts/public/test_info/browsertime-results.tgz) | [Before](https://profiler.firefox.com/from-url/https%3A%2F%2Ffirefox-ci-tc.services.mozilla.com%2Fapi%2Fqueue%2Fv1%2Ftask%2FBVv-1FiHRcaYKEIlQi0u5A%2Fruns%2F0%2Fartifacts%2Fpublic%2Ftest_info%2Fprofile_google-mail.zip)/[After](https://profiler.firefox.com/from-url/https%3A%2F%2Ffirefox-ci-tc.services.mozilla.com%2Fapi%2Fqueue%2Fv1%2Ftask%2FF0S6VX8VSm2Zgz9leDjlcw%2Fruns%2F0%2Fartifacts%2Fpublic%2Ftest_info%2Fprofile_google-mail.zip) |
| [9%](https://treeherder.mozilla.org/perfherder/graphs?timerange=1209600&series=autoland,4405895,1,13)  | [bing-search](https://firefox-source-docs.mozilla.org/testing/perfdocs/raptor.html#bing-search-d) ContentfulSpeedIndex | macosx1015-64-shippable-qr | bytecode-cached cold fission webrender | [254.94](https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/bz5OcQg0ToeZdiuSLDN07A/runs/0/artifacts/public/test_info/browsertime-results.tgz) -> [278.52](https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/cr0UuI6kS7KaBW-dn3dEPA/runs/0/artifacts/public/test_info/browsertime-results.tgz) | [Before](https://profiler.firefox.com/from-url/https%3A%2F%2Ffirefox-ci-tc.services.mozilla.com%2Fapi%2Fqueue%2Fv1%2Ftask%2Fbz5OcQg0ToeZdiuSLDN07A%2Fruns%2F0%2Fartifacts%2Fpublic%2Ftest_info%2Fprofile_bing-search.zip)/[After](https://profiler.firefox.com/from-url/https%3A%2F%2Ffirefox-ci-tc.services.mozilla.com%2Fapi%2Fqueue%2Fv1%2Ftask%2Fcr0UuI6kS7KaBW-dn3dEPA%2Fruns%2F0%2Fartifacts%2Fpublic%2Ftest_info%2Fprofile_bing-search.zip) |
| [7%](https://treeherder.mozilla.org/perfherder/graphs?timerange=1209600&series=autoland,4405899,1,13)  | [bing-search](https://firefox-source-docs.mozilla.org/testing/perfdocs/raptor.html#bing-search-d) SpeedIndex | macosx1015-64-shippable-qr | bytecode-cached cold fission webrender | [326.73](https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/bz5OcQg0ToeZdiuSLDN07A/runs/0/artifacts/public/test_info/browsertime-results.tgz) -> [349.24](https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/cr0UuI6kS7KaBW-dn3dEPA/runs/0/artifacts/public/test_info/browsertime-results.tgz) | [Before](https://profiler.firefox.com/from-url/https%3A%2F%2Ffirefox-ci-tc.services.mozilla.com%2Fapi%2Fqueue%2Fv1%2Ftask%2Fbz5OcQg0ToeZdiuSLDN07A%2Fruns%2F0%2Fartifacts%2Fpublic%2Ftest_info%2Fprofile_bing-search.zip)/[After](https://profiler.firefox.com/from-url/https%3A%2F%2Ffirefox-ci-tc.services.mozilla.com%2Fapi%2Fqueue%2Fv1%2Ftask%2Fcr0UuI6kS7KaBW-dn3dEPA%2Fruns%2F0%2Fartifacts%2Fpublic%2Ftest_info%2Fprofile_bing-search.zip) |
### Improvements:

| **Ratio** | **Test** | **Platform** | **Options** | **Absolute values (old vs new)** |  **Performance Profiles** | 
|--|--|--|--|--|--| 
| [6%](https://treeherder.mozilla.org/perfherder/graphs?timerange=1209600&series=autoland,4060423,1,13)  | [reddit-billgates-post-1.billg](https://firefox-source-docs.mozilla.org/testing/perfdocs/raptor.html#reddit-billgates-post-1-i) fcp | windows10-64-shippable-qr | cold fission webrender | 215.15 -> 203.25 |  |
| [6%](https://treeherder.mozilla.org/perfherder/graphs?timerange=1209600&series=autoland,4060431,1,13)  | [reddit-billgates-post-1.posts](https://firefox-source-docs.mozilla.org/testing/perfdocs/raptor.html#reddit-billgates-post-1-i) fcp | windows10-64-shippable-qr | cold fission webrender | 215.15 -> 203.25 |  |
| [4%](https://treeherder.mozilla.org/perfherder/graphs?timerange=1209600&series=autoland,4405937,1,13)  | [cnn](https://firefox-source-docs.mozilla.org/testing/perfdocs/raptor.html#cnn-d) fcp | macosx1015-64-shippable-qr | bytecode-cached cold fission webrender | 601.81 -> 575.72 | [Before](https://profiler.firefox.com/from-url/https%3A%2F%2Ffirefox-ci-tc.services.mozilla.com%2Fapi%2Fqueue%2Fv1%2Ftask%2FEqqPDKJCSC2l6kZ3QzmX7g%2Fruns%2F0%2Fartifacts%2Fpublic%2Ftest_info%2Fprofile_cnn.zip)/[After](https://profiler.firefox.com/from-url/https%3A%2F%2Ffirefox-ci-tc.services.mozilla.com%2Fapi%2Fqueue%2Fv1%2Ftask%2FcJk6lJUVTi6tZltJHQ6gZw%2Fruns%2F0%2Fartifacts%2Fpublic%2Ftest_info%2Fprofile_cnn.zip) |
| [4%](https://treeherder.mozilla.org/perfherder/graphs?timerange=1209600&series=autoland,3870002,1,13)  | [twitter](https://firefox-source-docs.mozilla.org/testing/perfdocs/raptor.html#twitter-d) fcp | windows10-64-shippable-qr | cold fission webrender | 153.04 -> 146.44 |  |


Details of the alert can be found in the [alert summary](https://treeherder.mozilla.org/perfherder/alerts?id=39254), including links to graphs and comparisons for each of the affected tests. Please follow our [guide to handling regression bugs](https://wiki.mozilla.org/TestEngineering/Performance/Handling_regression_bugs) and **let us know your plans within 3 business days, or the offending patch(es) may be backed out** in accordance with our [regression policy](https://www.mozilla.org/en-US/about/governance/policies/regressions/).

If you need the profiling jobs you can trigger them yourself from treeherder job view or ask a sheriff to do that for you.

For more information on performance sheriffing please see our [FAQ](https://wiki.mozilla.org/TestEngineering/Performance/FAQ).