Scroll performance

ndixon · Post by **ndixon** » May 13th, 2008, 3:51 am

kindofabuzz wrote:Disable smooth srolling and your problem is pretty much solved. pretty ironic huh?

The Firefox help says:

Use smooth scrolling
Smooth scrolling can be very useful if you read a lot of long pages. Normally, when you press Page Down, the view jumps directly down one page. With smooth scrolling, it slides down smoothly, so you can see how much it scrolls. This makes it easier to resume reading from where you were before.

Smooth scrolling seems to work reasonably well when using Page Up/Page Down; the problem is with mouse-wheel scrolling.

With that in mind, maybe we should have an extra checkbox in the UI to disable smooth mouse scrolling even when smooth scrolling is in effect.

Alternatively, could Firefox time the display updates, and abandon smooth (mouse-)scrolling when updates are too slow?

Faruk · Post by **Faruk** » May 17th, 2008, 3:55 am

Scroll issue continue on Firofox 3.0 RC1

teoli2003 · Post by **teoli2003** » May 17th, 2008, 8:41 am

Faruk, have you read the previous answers? It has been said that the scrolling problem need the new Compositor. And the new Compositor will be developped only *after* the release of Fx 3.

So it is expected that the scrolling problem will not be fixed in Fx 3 RC1, Fx 3 final or even Fx 3.0.x .

Faruk · Post by **Faruk** » May 17th, 2008, 9:53 am

teoli2003 wrote:Faruk, have you read the previous answers? It has been said that the scrolling problem need the new Compositor. And the new Compositor will be developped only *after* the release of Fx 3.

So it is expected that the scrolling problem will not be fixed in Fx 3 RC1, Fx 3 final or even Fx 3.0.x .

Ok i see now and thank you for information.

the_dees · Post by **the_dees** » May 17th, 2008, 12:41 pm

It seems, the Compositor is not even planned for 3.1 but for the big (thus far in the future) Moz2 release. Sad, because it was formerly top priority after 1.9

watervole02 · Post by **watervole02** » May 17th, 2008, 1:29 pm

the_dees wrote:It seems, the Compositor is not even planned for 3.1 but for the big (thus far in the future) Moz2 release. Sad, because it was formerly top priority after 1.9

From what I've read, compositor is a major addition to firefox, so it makes sense that compositor would land in moz2 rather than 1.9.next.

enmusubicci · Post by **enmusubicci** » May 19th, 2008, 1:55 pm

I have high CPU load when scrolling a page with RC1.

I think mostly due to images. For example here: http://sf-fantasy-books.blogspot.com/

The difference is extremely noticeable if I go back between Firefox 2 (works smoothly) and RC1.

Something must have broken in between. Firefox 3 is publicized to have better performance. In my case it has a MUCH worse performance.

suser · Post by **suser** » May 20th, 2008, 3:32 am

teoli2003 wrote:Faruk, have you read the previous answers? It has been said that the scrolling problem need the new Compositor. And the new Compositor will be developped only *after* the release of Fx 3.

So it is expected that the scrolling problem will not be fixed in Fx 3 RC1, Fx 3 final or even Fx 3.0.x .

I cant help, but I find such a reply rather disappointing (I am aware that it wasnt actually your reply). Firefox 3 (as any new version of a product) should bring major additions and improvements over Firefox 2. As far as it seems now however, Firefox 3's Compositor has a far worse performance than Firefox 2's.

Personally I wonder how Firefox 3 came out of (respectively even into) the Beta phase, with such backdraws.

asquithea · Post by **asquithea** » May 20th, 2008, 4:02 am

Bluntly, because the changes fixed many layout issues. Some types of pages got faster, and some (probably more) got slower. The developers accepted the performance hit on the basis that future changes to the layout engine will be faster than the Fx2 code.

suser · Post by **suser** » May 20th, 2008, 6:59 am

Thanks asquithea, even though - to be honest - I have yet to see the big performance improvement of 3 over 2 there are a couple of nice new features I would really like to use. In particular I was excited about the tagging and easy bookmarking (and this although I have never really used bookmarks ever since Netscape 4), the new url bar and a few other new features, however after those news this excitement turned down quite a bit with these news and now I am not sure whether I will upgrade.

I have to admit I dont use Firefox 3 as full-time browser yet, but all my quick tests never showed a real improvement of performance over Firefox 2 (where personally I never complained about performance issues, apart temporary blocking sometimes during a page load - was this resolved in Firefox 3?), on the other hand this issue is something I clearly notice.

Bluefang · Post by **Bluefang** » May 20th, 2008, 9:02 am

Yeah, I haven't noticed much speed improvements in Windows, however little I use it. However the speed improvements in Linux are very noticeable.

Also, page rendering may not be improved, but a lot of speed improvements were make in the JavaScript engine. which may not be immediately apparent if you don't browse a lot of JS heavy sites.

suser · Post by **suser** » May 20th, 2008, 12:16 pm

Bluefang wrote:Yeah, I haven't noticed much speed improvements in Windows, however little I use it. However the speed improvements in Linux are very noticeable.

Good for the Linux folks, but I'd assume Windows is still in the majority. So basically it would seem instead of an improvement, Firefox' performance decreased on Windows. From this, maybe it might be even the better choice to offer a Firefox 3 with a Firefox 2 engine for Windows

.

Bluefang wrote:Also, page rendering may not be improved, but a lot of speed improvements were make in the JavaScript engine. which may not be immediately apparent if you don't browse a lot of JS heavy sites.

I am sorry, once more I cant comment on this, but not only because - as I mentioned - I dont use Firefox 3 full-time but also because my typical sites arent that JavaScriptish, which also never made me complain about Firefox 2's speed.

IMHO it would have been more important to have an improved (or at least equally fast) render process than a possibly faster Javascript processing, each page needs to be rendered but not each uses heavy Javascript code.

I know, my complaints here are rather fruitless

, I guess I am just disappointed .....

Stifu · Post by **Stifu** » May 20th, 2008, 1:05 pm

Those occasional bad scrolling performances aside, I can say Firefox 3 is overall significantly faster for me, on Windows.
And speed aside, I wouldn't want to go back to the Firefox 2 engine, that'd be just too much of a downgrade.

suser · Post by **suser** » May 20th, 2008, 2:06 pm

Stifu wrote:Those occasional bad scrolling performances aside, I can say Firefox 3 is overall significantly faster for me, on Windows.

Well, as I said I am not using Firefox 3 full-time so I cant say it to the fullest extent but my quick adventures didnt give me the wow-effect, maybe because I am not on Vista yet

. The last time I had this was with Opera 9.5, in terms of speed at least.

The weird thing is, I just ran the latest nightly and the scrolling on some sites was much better than yesterday - and I honestly dont think these issues were fixed since yesterday. The bad performance remains however at these sites

http://www.gameswelt.de
http://www.cssmagazine.it

Stifu wrote:And speed aside, I wouldn't want to go back to the Firefox 2 engine, that'd be just too much of a downgrade.

A particular reason why? To be honest I dont notice that much of a difference.

Stifu · Post by **Stifu** » May 20th, 2008, 11:54 pm

suser wrote:
Stifu wrote:And speed aside, I wouldn't want to go back to the Firefox 2 engine, that'd be just too much of a downgrade.

A particular reason why? To be honest I dont notice that much of a difference.

Well, I'm a web developer...
So I don't want to part with full-page zoom, smooth rounded borders, SVG blur, the various CSS fixes and additions (like selectors that support dynamic changes now), and so on.