165411 - High CPU usage on end of selection change in Composer (HTML/mail)

Status: NEW

(Core :: DOM: Selection, defect, P5)

Description

[Tom Mraz]

Linux trunk 2002082808 - present on much older builds too (f.e. 1.1a and older). 
No problem on Windows.

If you open some large page in composer or enter some large enough (many pages)
bogus text and try to make a large part of it selected by click-drag there is a
period (2-10 seconds on my computer depending on size of the selected text) of
100% CPU usage when you stop selecting. The UI is stalled for that period.

I don't see such high CPU usage when selecting on textareas, in a plain browser
window or in the HTML source view in the Composer.

I think it could be somehow connected to automatic copying of the selection
contents to the X Window clipboard but it's strange that in the browser there is
no such CPU usage spike at all.

Comment 1

[Neo Gigs]

I think the similar problem also occur in Mac OS X version of mozilla 1.7RC1,
never happened in 1.7Beta version of Mac OS X. The CPU keep on go high even when
typing on the Normal editing, no such problem in HTML Source edit.

(In reply to comment #0)
> Linux trunk 2002082808 - present on much older builds too (f.e. 1.1a and older). 
> No problem on Windows.
> 
> If you open some large page in composer or enter some large enough (many pages)
> bogus text and try to make a large part of it selected by click-drag there is a
> period (2-10 seconds on my computer depending on size of the selected text) of
> 100% CPU usage when you stop selecting. The UI is stalled for that period.
> 
> I don't see such high CPU usage when selecting on textareas, in a plain browser
> window or in the HTML source view in the Composer.
> 
> I think it could be somehow connected to automatic copying of the selection
> contents to the X Window clipboard but it's strange that in the browser there is
> no such CPU usage spike at all.

Comment 2

[Wayne Mery (:wsmwk)]

do you still see this?

Comment 3

[Jens Stutte [:jstutte]]

Bulk-downgrade of unassigned, >=5 years untouched DOM/Storage bugs' priority.

If you have reason to believe this is wrong (especially for the severity), please write a comment and ni :jstutte.