Open Bug 1626263 Opened 5 years ago Updated 2 years ago

High CPU load while waiting for a page to load (MacOS)

Categories

(Core :: Graphics, defect, P3)

74 Branch
defect

Tracking

()

Performance Impact low
Tracking Status
firefox75 --- wontfix
firefox76 --- wontfix
firefox77 --- wontfix
firefox78 --- wontfix

People

(Reporter: pygy79, Unassigned)

Details

(Keywords: perf:resource-use)

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:74.0) Gecko/20100101 Firefox/74.0

Steps to reproduce:

The CPU load while a tab is loading is surprisingly intensive.

Perhaps the bouncing ball animation?

Given the following NodeJS server that accepts requests but never responds.

require("http").createServer(console.log).listen(3000, e => console.log(e, " or running"))

Open a few tabs pointing to http://localhost:3000 and watch the Firefox CPU usage. Close the tabs and watch again.

Actual results:

High CPU load while the tabs are waiting for a reply, which drops as soon as the tabs are closed.

Expected results:

No noticeable CPU load for such a trivial task.

Whiteboard: [qf]

Bugbug thinks this bug should belong to this component, but please revert this change in case of error.

Component: Untriaged → Widget: Cocoa
Product: Firefox → Core
Component: Widget: Cocoa → Graphics

Can you attach the contents of your about:support as a text file?

Flags: needinfo?(pygy79)
Priority: -- → P3

Would you also please provide a profile during the CPU load? Thanks!
https://developer.mozilla.org/en-US/docs/Mozilla/Performance/Reporting_a_Performance_Problem

Whiteboard: [qf] → [qf:p3:resource]

I'll do that ASAP

I had missed the perf. issues reporting guidelines, thanks for the pointer

Flags: needinfo?(pygy79)

Because this bug's Severity has not been changed from the default since it was filed, and it's Priority is P3 (Backlog,) indicating it has been triaged, the bug's Severity is being updated to S3 (normal.)

Severity: normal → S3
Performance Impact: --- → P3
Whiteboard: [qf:p3:resource]

The bug has a release status flag that shows some version of Firefox is affected, thus it will be considered confirmed.

Status: UNCONFIRMED → NEW
Ever confirmed: true
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