kinto-offline-client.js is being loaded by the blocklist updater, and can cause us to skip a frame

RESOLVED FIXED

Status

enhancement
RESOLVED FIXED
2 years ago
2 years ago

People

(Reporter: mconley, Assigned: leplatrem)

Tracking

unspecified
Points:
---
Dependency tree / graph

Firefox Tracking Flags

(firefox55 fixed)

Details

Attachments

(1 attachment)

Here's a profile I captured: https://perf-html.io/public/20232669f468e741f89f237bc9612ec0c4792596/calltree/?range=127.2570_130.2583~128.8764_128.9363&thread=0

It looks like the blocklist updater is somehow kicking this off.

This is the sort of papercut that can cause us to periodically jank the browser UI, and we should avoid this (or do a better job of hiding it) if at all possible.
Assignee

Comment 1

2 years ago
Indeed, I can confirm: https://dxr.mozilla.org/mozilla-central/rev/722fdbff1efc308a22060e75b603311d23541bb5/toolkit/mozapps/extensions/nsBlocklistService.js#606-608

We could import the module on startup, especially now that it is enabled by default.
Assignee

Updated

2 years ago
Assignee: nobody → mathieu
(In reply to Mathieu Leplatre (:leplatrem) from comment #1)
> Indeed, I can confirm:
> https://dxr.mozilla.org/mozilla-central/rev/
> 722fdbff1efc308a22060e75b603311d23541bb5/toolkit/mozapps/extensions/
> nsBlocklistService.js#606-608
> 
> We could import the module on startup, especially now that it is enabled by
> default.

We usually prefer to move as much as we can off the startup path. This may be another case where we need to run something on the ui thread while it is idle (ie. we would need bug 1353206).
Alternatively, (and I'm likely exposing my ignorance of what Kinto's function is in Firefox, but) is it possible to initialize the module lazily?
Comment hidden (mozreview-request)
Assignee

Comment 5

2 years ago
Mike, 
I submitted a patch that loads the module lazily. Let me know if that works for you :)
Thanks for suggesting this!
Flags: needinfo?(mconley)
Thanks leplatrem - while I did advise the change, I suspect MattN would be a better reviewer here (since I'm both on PTO, and also unfamiliar with this particular component).
Flags: needinfo?(mconley)
Reporter

Updated

2 years ago
Attachment #8859924 - Flags: review?(mconley) → review?(MattN+bmo)

Comment 7

2 years ago
mozreview-review
Comment on attachment 8859924 [details]
Bug 1357116 - Load the blocklist updater module lazily

https://reviewboard.mozilla.org/r/131984/#review136826

Unfortunately this won't help, the "resource://services-common/blocklist-updater.js" module (and all its dependencies) will be imported synchronously when executing BlocklistUpdater.checkVersions().

From looking in the profile in comment 0, it seems accessing anything in Kinto initializes all (or most) of it synchronously. Or at least, it's in resource://services-common/blocklist-clients.js and its dependencies that the time is spent.
Attachment #8859924 - Flags: review-
Attachment #8859924 - Flags: review?(MattN+bmo)
Comment hidden (mozreview-request)
Assignee

Comment 9

2 years ago
Thanks for your precious feedback! I was in the dark here..

I changed several direct imports to lazy module getters. Tests seem to pass locally :)

Is there a way to also lazy load ``Cu.importGlobalProperties(["fetch"]);``?
Flags: needinfo?(florian)
Assignee

Updated

2 years ago
See Also: → 1257565

Comment 10

2 years ago
mozreview-review
Comment on attachment 8859924 [details]
Bug 1357116 - Load the blocklist updater module lazily

https://reviewboard.mozilla.org/r/131984/#review136922

Removing review flag for now as there are several test failures on try.

The nsBlocklistService.js changes won't actually help performance, as the module will be loaded at the first BlocklistUpdater.checkVersions() call, and attempting to load again an already loaded module is cheap. But I don't mind if you keep them.

The rest of the patch looks good to me, thanks! From code inspection I think it fixes the bug (but I haven't tried to test the patch locally). I'm ok with r+'ing these changes, but I'm not officially a reviewer for services/common.

(In reply to Mathieu Leplatre (:leplatrem) from comment #9)

> Is there a way to also lazy load ``Cu.importGlobalProperties(["fetch"]);``?

XPCOMUtils.defineLazyGetter would probably work for that, but it doesn't seem useful. I think importing a global property is cheap.
Attachment #8859924 - Flags: review?(florian)
Comment hidden (mozreview-request)
Assignee

Comment 12

2 years ago
Thanks for the feedback and your help :)

> Removing review flag for now as there are several test failures on try.

Sorry for that, I now fixed the code/tests.

> I'm not officially a reviewer for services/common.

I will request a review from Mark then.
Assignee

Updated

2 years ago
Attachment #8859924 - Flags: review?(mgoodwin)
Assignee

Updated

2 years ago
Blocks: 1257565

Comment 13

2 years ago
mozreview-review
Comment on attachment 8859924 [details]
Bug 1357116 - Load the blocklist updater module lazily

https://reviewboard.mozilla.org/r/131984/#review137362

Looks good to me, but let's wait for Mark's review :-).
Attachment #8859924 - Flags: review?(florian) → review+

Comment 14

2 years ago
mozreview-review
Comment on attachment 8859924 [details]
Bug 1357116 - Load the blocklist updater module lazily

https://reviewboard.mozilla.org/r/131984/#review138492
Attachment #8859924 - Flags: review?(mgoodwin) → review+
Assignee

Updated

2 years ago
Keywords: checkin-needed

Comment 15

2 years ago
Pushed by ryanvm@gmail.com:
https://hg.mozilla.org/integration/autoland/rev/83fe6517d5be
Load the blocklist updater module lazily r=florian,mgoodwin
Keywords: checkin-needed
Backed out for eslint failures in blocklist-clients.js:

https://hg.mozilla.org/integration/autoland/rev/ab3f508d6afd858476d61638b43a71b67f9250f2

Push with failure: https://treeherder.mozilla.org/#/jobs?repo=autoland&revision=83fe6517d5bed5ee65f76618decb29389bfe383c&filter-resultStatus=testfailed&filter-resultStatus=busted&filter-resultStatus=exception&filter-resultStatus=retry&filter-resultStatus=usercancel&filter-resultStatus=runnable
Failure log: https://treeherder.mozilla.org/logviewer.html#?job_id=95997686&repo=autoland

[task 2017-05-02T17:25:43.441953Z] TEST-UNEXPECTED-ERROR | /home/worker/checkouts/gecko/services/common/blocklist-clients.js:22:60 | Multiple spaces found before '"resource://services-common/kinto-offline-client.js"'. (no-multi-spaces)
[task 2017-05-02T17:25:43.442074Z] TEST-UNEXPECTED-ERROR | /home/worker/checkouts/gecko/services/common/blocklist-clients.js:24:60 | Multiple spaces found before '"resource://services-common/kinto-storage-adapter.js"'. (no-multi-spaces)
[task 2017-05-02T17:25:43.442153Z] TEST-UNEXPECTED-ERROR | /home/worker/checkouts/gecko/services/common/blocklist-clients.js:25:60 | Multiple spaces found before '"resource://gre/modules/CanonicalJSON.jsm"'. (no-multi-spaces)
Flags: needinfo?(mathieu)
Comment hidden (mozreview-request)
Comment hidden (mozreview-request)
Assignee

Updated

2 years ago
Flags: needinfo?(mathieu)
Keywords: checkin-needed

Comment 19

2 years ago
Pushed by ryanvm@gmail.com:
https://hg.mozilla.org/integration/autoland/rev/4f511c0a0d70
Load the blocklist updater module lazily r=florian,mgoodwin
Keywords: checkin-needed

Comment 20

2 years ago
bugherder
https://hg.mozilla.org/mozilla-central/rev/4f511c0a0d70
Status: NEW → RESOLVED
Closed: 2 years ago
Resolution: --- → FIXED
Flags: needinfo?(florian)
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