1485015 - 100.88% sccache requests_not_cacheable (windows2012-64) regression on push 990f081377ee (Tue Aug 21 2018)

Status: RESOLVED INVALID

(Firefox Build System :: General, defect)

Description

[Ionuț Goldan [:igoldan]]

We have detected a build metrics regression from push:

https://hg.mozilla.org/integration/mozilla-inbound/rev/990f081377ee

As author of one of the patches included in that push, we need your help to address this regression.

Regressions:

101%  sccache requests_not_cacheable windows2012-64 pgo taskcluster-c4.4xlarge     3,712.75 -> 7,458.00
  9%  sccache hit rate windows2012-64 pgo taskcluster-c4.4xlarge     1.00 -> 0.91


You can find links to graphs and comparison views for each of the above tests at: https://treeherder.mozilla.org/perf.html#/alerts?id=15171

On the page above you can see an alert for each affected platform as well as a link to a graph showing the history of scores for this test. There is also a link to a treeherder page showing the jobs in a pushlog format.

To learn more about the regressing test(s), please see: https://developer.mozilla.org/en-US/docs/Mozilla/Performance/Automated_Performance_Testing_and_Sheriffing/Build_Metrics

Comment 1

[Mike Hommey [:glandium]]

This is misattributed. The culprit is bug 1484882, and that's not really a regression. The problem is that previously, sccache would die because of too long idle (presumably, while doing the libxul LTO linkage/compilation) and we'd only get partial data for sccache stats.

With bug 1484882, sccache doesn't die idle, and we finally get full stats.