1334940 - Re-enable SCCACHE for linux64-ccov builds

Status: RESOLVED FIXED

(Testing :: Code Coverage, defect)

Description

[u587052]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:51.0) Gecko/20100101 Firefox/51.0
Build ID: 20170126200443

Steps to reproduce:

Run a build on taskcluster with sccache enabled. For example, see: https://treeherder.mozilla.org/#/jobs?repo=try&revision=8002f88014f819ce34055db8ecf72c0e1ceb2b4a&selectedJob=68153184 (232kB gcno archive)


Actual results:

The produced "gcno" archive is missing most of the "gcno" files, and is undersized.


Expected results:

Build running with sccache should properly track the "gcno" files. When the final "gcno" archive is created as an artifact, it should be around ~75mB

Comment 1

[u587052]

Backstory:
1. linux64-ccov builds were producing incomplete gcno issues
2. Cause was determined to be incorrect sccache interaction: https://bugzilla.mozilla.org/show_bug.cgi?id=1332917#c18
3. sccache is being disabled for linux64-ccov builds: https://bugzilla.mozilla.org/show_bug.cgi?id=1334402

Comment 2

[Marco Castelluccio [:marco]]

Ted, Chris, I think this is pretty important for build times, right? Do you know what kind of improvement would be expected by using sccache?
I've filed https://github.com/mozilla/sccache/issues/258 to add support to sccache.

Comment 3

[(not currently active) Ted Mielczarek]

Somewhere in this ballpark, presumably:
https://treeherder.mozilla.org/perf.html#/graphs?series=mozilla-inbound,1682429,1,2&series=mozilla-inbound,1582370,1,2

The "plain" builds build without sccache (for measuring build system times without the noise introduced by sccache caching). You can see that the "build times opt plain" measurement is fairly consistent, and the "build times opt" measurement (which does use sccache) is quite a bit lower but variable.

Comment 4

[Chris Manchester (limited bugmail, email directly)]

I don't have any more info on this. As long as they only run in a few configurations I don't think the efficiency of these builds would be a big concern from an infrastructure capacity standpoint.

Comment 5

[Gabriel Vîjială [:gabriel-v]]

I'm working on https://github.com/mozilla/sccache/issues/258. 

1. Here's a try build without changing anything:
https://treeherder.mozilla.org/#/jobs?repo=try&revision=6572946785b53fc9959a28183eb6299195d16cfd

2. Here's a try build that just enables sccache, without patching it (to see if the problem is still there):
https://treeherder.mozilla.org/#/jobs?repo=try&revision=f27039c3af59f5524ef9acacb6349951ca8d5c63

3. And here's a try build that uses the patched sccache that I've been working on:
https://treeherder.mozilla.org/#/jobs?repo=try&revision=e8046c858ca85cc80016e5db6520cd08e99d0015

The gcno archives for build #1 and #3 are roughly the same, 75.9mb. I'll update with build #2 once it's done.

Comment 6

[Gabriel Vîjială [:gabriel-v]]

Interesting enough, build #2 produces a gcno archive of roughly the same size as the other ones, 75.9mb, but it's missing some files. Builds #1 and #3 have the same files.

Comment 7

[Gabriel Vîjială [:gabriel-v]]

Attachment: Bug 1334940 - Re-enable SCCACHE for linux64-ccov.

Review commit: https://reviewboard.mozilla.org/r/256876/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/256876/

Comment 8

[Gabriel Vîjială [:gabriel-v]]

try: https://treeherder.mozilla.org/#/jobs?repo=try&revision=f0afde4f5664b28a4be8c9940309f498a83bac2a

Comment 9

[(not currently active) Ted Mielczarek]

Comment on attachment 8991977 [details]
Bug 1334940 - Re-enable SCCACHE for linux64-ccov.

https://reviewboard.mozilla.org/r/256876/#review264400

Thanks for fixing the sccache issue!

Comment 10

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/f41fb72f94b6
Re-enable SCCACHE for linux64-ccov. r=ted

Comment 11

[Eliza Balazs [:ebalazs_]]

https://hg.mozilla.org/mozilla-central/rev/f41fb72f94b6