adjustTabstrip is slow, due to flushing layout

RESOLVED FIXED in Firefox 55

Status

()

enhancement
P1
normal
RESOLVED FIXED
2 years ago
2 years ago

People

(Reporter: florian, Assigned: dao)

Tracking

(Blocks 2 bugs)

unspecified
Firefox 55
Points:
---
Dependency tree / graph
Bug Flags:
qe-verify -

Firefox Tracking Flags

(firefox55 fixed)

Details

(Whiteboard: [photon-performance])

Attachments

(1 attachment)

Reporter

Description

2 years ago
On a fast last generation macbook, I just had adjustTabstrip cause 37ms of jank (within 700ms of jank while detaching a mozreview tab to a new window). These 37ms are spent flushing layout.

I'm almost sure this layout flush isn't needed, because on one window I had several hundred tabs, so removing one won't change anything to what we do with close tab icons, and the new window had only one tab so we could guess easily without flushing that there was plenty of room.

Could we somehow use overflow/underflow event to replace this code?
Or would get use getBoundsWithoutFlushing to get a rought estimate, and if it's close to the threshold do an actual flush?
Reporter

Updated

2 years ago
See Also: → 1356707
Assignee

Updated

2 years ago
See Also: 1356707
Assignee

Updated

2 years ago
Duplicate of this bug: 1356707
Assignee

Updated

2 years ago
Flags: needinfo?(dao+bmo)
Flags: qe-verify?
Priority: -- → P2
Assignee

Comment 2

2 years ago
(In reply to Florian Quèze [:florian] [:flo] from comment #0)
> Could we somehow use overflow/underflow event to replace this code?

The tab clip width is intentionally larger than the tab minimum width, so we can't replace this code, but we can return early if we're overflowing.
Assignee: nobody → dao+bmo
Status: NEW → ASSIGNED
Flags: needinfo?(dao+bmo)
Assignee

Updated

2 years ago
Flags: qe-verify? → qe-verify-
Priority: P2 → P1
Comment hidden (mozreview-request)
Reporter

Comment 4

2 years ago
mozreview-review
Comment on attachment 8858644 [details]
Bug 1356655 - Let adjustTabstrip return early if the tab strip is overflowing.

https://reviewboard.mozilla.org/r/130612/#review133212

Thanks for looking into this! :-)

::: browser/base/content/tabbrowser.xml:5934
(Diff revision 1)
>  
>        <method name="adjustTabstrip">
>          <body><![CDATA[
> +          // If we're overflowing, tab widths don't change anymore, so we can
> +          // return early to avoid flushing layout.
> +          if (this.getAttribute("overflow") == "true") {

I started looking at the code to try to find the answer to this question, but you probably know it or can find it faster than me: will adjustTabstrip be called again after we remove the 'overflow' attribute?
I assume if we are removing it because we closed just one tab it won't matter, but if we removed plenty of tabs (eg. we triggered removeTabsToTheEndFrom from the third tab), it may change whether we need to display the close buttons.
Assignee

Comment 5

2 years ago
(In reply to Florian Quèze [:florian] [:flo] from comment #4)
> I started looking at the code to try to find the answer to this question,
> but you probably know it or can find it faster than me: will adjustTabstrip
> be called again after we remove the 'overflow' attribute?
> I assume if we are removing it because we closed just one tab it won't
> matter, but if we removed plenty of tabs (eg. we triggered
> removeTabsToTheEndFrom from the third tab), it may change whether we need to
> display the close buttons.

We call adjustTabstrip in _endRemoveTab.
Reporter

Comment 6

2 years ago
mozreview-review
Comment on attachment 8858644 [details]
Bug 1356655 - Let adjustTabstrip return early if the tab strip is overflowing.

https://reviewboard.mozilla.org/r/130612/#review133888
Attachment #8858644 - Flags: review?(florian) → review+

Comment 7

2 years ago
Pushed by dgottwald@mozilla.com:
https://hg.mozilla.org/integration/autoland/rev/7640ebe4a0e2
Let adjustTabstrip return early if the tab strip is overflowing. r=florian

Comment 8

2 years ago
bugherder
https://hg.mozilla.org/mozilla-central/rev/7640ebe4a0e2
Status: ASSIGNED → RESOLVED
Last Resolved: 2 years ago
Resolution: --- → FIXED
Target Milestone: --- → Firefox 55
Iteration: --- → 55.4 - May 1
See Also: → 1354194
Reporter

Updated

2 years ago
See Also: → 1358721
Assignee

Updated

2 years ago
Blocks: 1358721
See Also: 1358721
Reporter

Updated

2 years ago
No longer blocks: photon-performance-triage
Assignee

Updated

2 years ago
Depends on: 1366473
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