Bug: 35.81 - 26.37% browser_translations_perf_es_en.js total-translation-time / browser_translations_perf_es_en.js words-per-second + 4 more (Linux, OSX) regression on Thu January 16 2025
Status: RESOLVED
Priority: --
Resolution: WONTFIX
Created: 2025-01-21 09:59:14+00:00
Resolved: 2025-01-21 13:40:03+00:00

Perfherder has detected a mozperftest performance regression from push [1aa0f6d15f0fe0f9ba6ebd69f09ba0a337b21a63](https://hg.mozilla.org/integration/autoland/pushloghtml?changeset=1aa0f6d15f0fe0f9ba6ebd69f09ba0a337b21a63). 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)** |  
|--|--|--|--|--| 
| [36%](https://treeherder.mozilla.org/perfherder/graphs?timerange=1209600&series=autoland,5196542,1,15)  | browser_translations_perf_es_en.js total-translation-time | linux1804-64-shippable |  | 5.92 -> 8.04 | 
| [35%](https://treeherder.mozilla.org/perfherder/graphs?timerange=1209600&series=autoland,5196552,1,15)  | browser_translations_perf_es_en.js total-translation-time | macosx1015-64-shippable-qr |  | 6.08 -> 8.23 | 
| [27%](https://treeherder.mozilla.org/perfherder/graphs?timerange=1209600&series=autoland,5196550,1,15)  | browser_translations_perf_es_en.js tokens-per-second | macosx1015-64-shippable-qr |  | 1,820.09 -> 1,334.57 | 
| [27%](https://treeherder.mozilla.org/perfherder/graphs?timerange=1209600&series=autoland,5196549,1,15)  | browser_translations_perf_es_en.js words-per-second | macosx1015-64-shippable-qr |  | 1,152.54 -> 845.09 | 
| [26%](https://treeherder.mozilla.org/perfherder/graphs?timerange=1209600&series=autoland,5196540,1,15)  | browser_translations_perf_es_en.js tokens-per-second | linux1804-64-shippable |  | 1,853.26 -> 1,364.56 | 
| [26%](https://treeherder.mozilla.org/perfherder/graphs?timerange=1209600&series=autoland,5196539,1,15)  | browser_translations_perf_es_en.js words-per-second | linux1804-64-shippable |  | 1,173.54 -> 864.08 | 
### Improvements:

| **Ratio** | **Test** | **Platform** | **Options** | **Absolute values (old vs new)** |  
|--|--|--|--|--| 
| [4%](https://treeherder.mozilla.org/perfherder/graphs?timerange=1209600&series=autoland,5196538,1,15)  | browser_translations_perf_es_en.js engine-init-time | linux1804-64-shippable |  | 360.19 -> 345.50 | 


Details of the alert can be found in the [alert summary](https://treeherder.mozilla.org/perfherder/alerts?id=43376), 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 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.

You can run all of these tests on try with `./mach try perf --alert 43376`

The following [documentation link](https://firefox-source-docs.mozilla.org/testing/perfdocs/mach-try-perf.html#running-alert-tests) provides more information about this command.

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

If you have any questions, please do not hesitate to reach out to bacasandrei@mozilla.com.