1815579 - Investigate janky Tabs Tray in Compose performance

Status: RESOLVED FIXED

(Fenix :: Performance, defect)

Description

[Matt Tighe [:matt-tighe]]

The Tabs Tray conversion in Compose runs noticeably slower than the XML version when many tabs (30+) are open. This was discovered during this investigation.

STR:

1. Open 30+ tabs in a debug build or build with the composeTabsTray otherwise enabled.
2. Scroll up and down continuously.

This will demonstrate the slowness and may even result in a crash with no Logcat entry or system dialog. This crash seems to be caused by hitting a hard memory limit.

Using the profiler @007 and I saw instances where the memory usage would continue to balloon as scrolling happened, until it became 4 or 5 times larger than idle. It would eventually drop down to nominal levels after some inactivity, but this seemed to take ~30 seconds. This memory ballooning seemed to be related to either Bitmap usage or Autosave::triggerSave.

These performance issues should be investigated and resolved before the feature can be released.

Comment 1

[Matt Tighe [:matt-tighe]]

Note that https://bugzilla.mozilla.org/show_bug.cgi?id=1815306#c7 includes a small script for launching a large number of tabs that may be helpful during investigation.

Comment 2

[Noah Bond [:007]]

This is likely due to how the Favicons are being loaded. The initial investigation here should be around the ThumbnailCard Composable which TabListItem and TabGriditem ultimately use.

Comment 3

[BMO Github Automation]

Attachment: [mozilla-mobile/firefox-android] Bug 1815579 - Improve performance of image loading in tab items (#2301)

Comment 4

[Marc Leclair [:mleclair]]

The Performance Impact Calculator has determined this bug's performance impact to be low. If you'd like to request re-triage, you can reset the Performance Impact flag to "?" or needinfo the triage sheriff.

Platforms: Android
Impact on browser: Causes noticeable jank

Comment 5

[BMO Github Automation]

Authored by https://github.com/MozillaNoah
https://github.com/mozilla-mobile/firefox-android/commit/7c16b379f8db19d03f2f902133be6b3226ee8ffd
[main] Bug 1815579 - Improve performance of image loading in tab items