1482052 - Add more sources to custom damp test for the debugger

Status: RESOLVED FIXED

(DevTools :: Debugger, enhancement, P3)

Description

[Yulia Startsev [:yulia] OOO until July 2026]

We recently introduced Lazy scripts to the debugger server, but we have not seen an impact on DAMP that we expected. This is likely due to the fact that none of our example tests have a sufficient number of files being loaded. We should add a large number of sources to the custom test and compare the results of this test to the revision before the lazy scripts landed in bug #1434305

Comment 1

[Yulia Startsev [:yulia] OOO until July 2026]

Attachment: Bug 1482052 - add talos test with many files for the debugger; r=ochameau

We do not have a test case in talos that has many files to be loaded on start. This change adds 100
files, each around 1000 lines long.

Comment 2

[Alexandre Poirot [:ochameau]]

* Instead of having 100 distinct files (and increasing m-c repo size),
can we have only one and trick the engine by using query strings like this:
  <script type="text/javascript" src="./js/test.js?id=1"></script>
  <script type="text/javascript" src="./js/test.js?id=2"></script>
  <script type="text/javascript" src="./js/test.js?id=3"></script>
  ...

* Can you attach links to perfherder compare pages?

* index.html would be more readable with `\n` after each `</script>`

* main.js and main.js.map have been renamed for some reason

Comment 3

[Yulia Startsev [:yulia] OOO until July 2026]

Changes have been made!

Before the lazy script work: https://treeherder.mozilla.org/#/jobs?repo=try&revision=11c3ececa5aa7ccbb731be8d771ff05d4ae09676


After the lazy script work: https://treeherder.mozilla.org/#/jobs?repo=try&revision=ca3fbe8b24c19b1cfa5cc0a9542ebf1377041306

Comparison between before and after: https://treeherder.mozilla.org/perf.html#/comparesubtest?originalProject=try&originalRevision=11c3ececa5aa7ccbb731be8d771ff05d4ae09676&newProject=try&newRevision=ca3fbe8b24c19b1cfa5cc0a9542ebf1377041306&originalSignature=f79b6a4f1f8f53326d3056f6c8008c0ff4de0a94&newSignature=f79b6a4f1f8f53326d3056f6c8008c0ff4de0a94&framework=1


Recent central: https://treeherder.mozilla.org/#/jobs?repo=try&revision=82853ef52634b1b35d7eeeb08a5ac2dad94b632f

Comparison between before and recent central: https://treeherder.mozilla.org/perf.html#/comparesubtest?originalProject=try&originalRevision=11c3ececa5aa7ccbb731be8d771ff05d4ae09676&newProject=try&newRevision=82853ef52634b1b35d7eeeb08a5ac2dad94b632f&originalSignature=f79b6a4f1f8f53326d3056f6c8008c0ff4de0a94&newSignature=f79b6a4f1f8f53326d3056f6c8008c0ff4de0a94&framework=1

Comment 4

[Yulia Startsev [:yulia] OOO until July 2026]

new try run just in case: https://treeherder.mozilla.org/#/jobs?repo=try&revision=e62ff23e57aa296048f22bf4344c3f8ccdfc9131

Comment 5

[Alexandre Poirot [:ochameau]]

console.autocomplete is 2 times slower with this patch.
Could you investigate that?

It is obvious that custom.jsdebugger will be slower.
I can also understand that tests running after debugger will be slightly slower due to GC increase.
But making a 1s test become a 2s one is suspicious.

It would be interesting to request a profile and see if there is any stack traces related to the debugger happening during autocomplete test.
I requested a profile on try run:
  https://treeherder.mozilla.org/#/jobs?repo=try&revision=82853ef52634b1b35d7eeeb08a5ac2dad94b632f&filter-searchStr=damp&selectedJob=193637294
Once it is done, it should be available in:
  Linux x64 Nightly opt -- T-P-e10s(damp)

Also note that on this try run, you can see an intermittent failure:
  PID 2218 | TEST-UNEXPECTED-FAIL | damp | debugger/custom.js: TypeError: source is undefined
  Only failed once on OSX:
  https://treeherder.mozilla.org/logviewer.html#?job_id=193637294&repo=try

Comment 6

[Alexandre Poirot [:ochameau]]

Comment on attachment 8999868 [details]
Bug 1482052 - add talos test with many files for the debugger; r=ochameau

Alexandre Poirot [:ochameau] has approved the revision.

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/9c29ffcfc052
add talos test with many files for the debugger; r=ochameau

Comment 8

[Daniel Varga [:dvarga]]

https://hg.mozilla.org/mozilla-central/rev/9c29ffcfc052

Comment 9

[Pulsebot]

Backout by [e-mail]:
https://hg.mozilla.org/mozilla-central/rev/00a5c0b3923a
Backed out changeset 9c29ffcfc052 for damp test failures a=backout

Comment 10

[Tiberius Oros[:tiberius_oros]]

Backed out changeset 9c29ffcfc052 (bug 1482052) for damp test failures 

Backout: https://hg.mozilla.org/mozilla-central/rev/00a5c0b3923abfcef338f7698c7d73e634395db8

Failure log file: https://treeherder.mozilla.org/logviewer.html#?job_id=195122545&repo=autoland&lineNumber=5083

Comment 11

[Yulia Startsev [:yulia] OOO until July 2026]

Try run for fix: https://treeherder.mozilla.org/#/jobs?repo=try&revision=78ca9cccefec17d0bc092e53416e4c090f8ca08e

Comment 12

[Yulia Startsev [:yulia] OOO until July 2026]

new try run: https://treeherder.mozilla.org/#/jobs?repo=try&revision=f07bd6e04eadd95146f0e0bfe4aaf3df0001a3c7

Comment 13

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/2ab5eba3c686
add talos test with many files for the debugger; r=ochameau

Comment 14

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/2ab5eba3c686