Bug Tracker

Opened 9 years ago

Closed 9 years ago

Last modified 9 years ago

#12269 closed bug (wontfix)

width() and height() significantly slower in 1.8 in WebKit browsers

Reported by: twadzilla Owned by: mikesherov
Priority: blocker Milestone: 1.8.1
Component: css Version: 1.8.0
Keywords: Cc:
Blocked by: Blocking:


jQuery version: 1.8

Browsers affected: Chrome 21-23, Safari 5-6

Browsers not affected: IE, Firefox

Operating systems: Windows XP SP3, Windows 7 x64, Mac OS 10.7

Repro link: http://jsfiddle.net/jkvFN/

Expected result: when applying width() or height() over a large (500+) collection of elements, performance should be roughly equivalent to css().

Actual result: width() and height() perform several orders of magnitude slower than css() in 1.8.0 compared to 1.7.2. A trace in the timeline feature of Chrome seems to indicate a large number of layout/style recalculations happening in curCSS (line 6617).

Change History (8)

comment:1 Changed 9 years ago by mikesherov

Component: unfiledcss
Keywords: needsdocs added
Priority: undecidedhigh
Resolution: worksforme
Status: newclosed

Actually, you should be happy. Change your tests to use jquery 1.7.2, and you'll see just how slow the old methods were. In jquery 1.8, I've significantly sped up certain code paths. As well, .width() as a setter and .css('width') as a setter do different things. .wdith() sets content width, where as .css('width') sets the "width" attribute, which can be content-width if box-sizing is content box, or content-width plus padding plus border if box-sizing is border-box.

Adding needsdocs because we haven't properly publicized this change.

comment:2 Changed 9 years ago by mikesherov

Resolution: worksforme
Status: closedreopened

Actually, maybe I got it backwards here. Sorry for that.

comment:3 Changed 9 years ago by mikesherov

Yeah, this is interesting. I apologize for the hasty reply. I'm investigating now.

comment:4 Changed 9 years ago by mikesherov

Right, so, this is slower in every browser, but more noticeable in webkit. This is due to what I had originally mentioned. It's still true that I've actually sped up some code paths when box-sizing:border-box is true, but also, we've become more precise with .width() vs. .css('width').

Again, .width() accounts for which box-sizing model is being used, and .css('width') does not. As a consequence, we query the box-sizing property when using .width(), which is the cause of the slowdown. Use .css('width') if you'd like to avoid this.

I'll continue to investigate this in the mean time.

comment:5 Changed 9 years ago by mikesherov

Milestone: None1.8.1
Owner: set to mikesherov
Priority: highblocker
Status: reopenedassigned

comment:6 Changed 9 years ago by mikesherov

Resolution: wontfix
Status: assignedclosed

We discussed this at length at the team meeting. We are keeping this behavior, as although it may be slower. If you are not using border-box, use .css('width'). If you need it to be content-width regardless of box-sizing, use .width().

comment:7 Changed 9 years ago by Andrés <[email protected]…>

almost same problem on firefox 14.0.1 so linux ubuntu 12. JQuery 1.8.0 Advertencia: Propiedad desconocida 'box-sizing'. Declaración rechazada.

comment:8 Changed 9 years ago by mikesherov

Keywords: needsdocs removed
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