Comments on Entropy Overload: Scrolling: Chrome vs Firefox

Given the appearance and rapid development of GPU-...

2010-12-22T09:31:51.691Z

Given the appearance and rapid development of GPU-accelerated rendering, I'm betting whatever finding holds now will not in six months.

In any case, I have the same finding - scrolling in chrome is juddery (particularly on CSS-heavy pages) and less so on FF. However, it's not always CPU-limited; sometimes it's spending just 2% of CPU time (less than FF), and it's still juddery - fairly consistently too, as if there's a frame-rate maximum hardcoded somewhere.

To those that think this doesn't matter: it does to me too. In fact, stuff like this present the most relevant performance benefit chrome has as well, such as switching between tabs or opening and closing them. UI latency matters; chrome's is generally excellent here and the small remaining issue of scrolling may well be addressed by hw-accel some time in the future.

I'm surprised that you haven't tested Oper...

2010-12-21T21:27:50.689Z

I'm surprised that you haven't tested Opera browser -- which IMHO is one of the best browsers, really fast!!

I guess it all boils down to how you scroll. I per...

2010-12-21T07:27:05.870Z

I guess it all boils down to how you scroll. I personally turn off the scroll widget, as it pollutes the middle-click functionality, and rarely scroll with the scrollbar, preferring either keys or mouse wheel, and for those, I can't reproduce your cpu usage spike on any of my machines (a quad-core desktop, a dual-core laptop and an atom netbook).

I tried on the 599+ post mega-thread on 64bit in non-tech.

That said, there is another option that could play a role, it's the "smooth scrolling" or something like that in the OS, which I also turn off along with the rest of the OS transition animations (because I want my menus to popup instantly, not wait for a silly fade-in or animation).

@Jolyon - Graphics card is ATI HD 5870, driver is ...

2010-12-20T20:22:10.491Z

@Jolyon - Graphics card is ATI HD 5870, driver is 2 months old. But the results also bear out on both of my laptops, one a Mac Air (so Nvidia 320M), the other Intel GMA. That's all three most common graphics card chipsets, from high end to lowest end. The CPU is no slouch either, an i7 @ 3.4MHz.

The jerkiness of the scrolling is most noticeable with the middle mouse click scroll widget - the little 4-way scroll icon that pops up, and causes scrolling depending on how far the cursor is from the icon.

It's also highly noticeable on the laptops when scrolling long documents (Google Reader's "infinite" reading list is a good example) with the keyboard.

Again, this isn't about initial rendering speed, bringing up a web page - that is IMO a relatively unimportant statistic, as I find the limiting factor for page load to be bandwidth - but simply scrolling around.

And it's not artificial for me. I tend to always be nervously scrolling around, usually with the middle button, and highlighting text. Chrome just feels "off", "juddery".

Using Chrome+ the utterly artificial scenario of c...

2010-12-20T20:10:42.802Z

Using Chrome+ the utterly artificial scenario of constantly wiggling the scrollbar failed to tip either of my paltry 2 CPU cores over 25% utilisation on a page with a normal/typical amount of content.

On the TRON dedicated talkback page on AICN (with a LARGE amount of content!) the same articifial exercise yielded 50% on each core.

But day to day *actual* real world scrolling has never been noticeably poor on Chrome+ for me.

Maybe Chrome+ is better than Chrome... I doubt it in this area. But I also wonder how your graphics card is set up, latest drivers etc... CPU load related to performance in the graphics domain is more often than not laid at the feet of the driver, not the app (not always, but very often). Plus I seem to recall reading that the latest and greatest GFX hardware is great at 3D but (relatively) is also (or can be) lousy at 2D, since the emphasis at the high end is on gaming.

I can scroll very smoothly in my Chrome. Haven'...

2010-12-20T18:54:52.730Z

I can scroll very smoothly in my Chrome. Haven't noticed any difference in my Chrome and Firefox. Mostly chrome beats Firefox in terms of rendering speed IMO. I can even enable GPU acceleration to speed things up in Chrome.

You could probably start an instance of Chrome, lo...

2010-12-20T18:54:48.234Z

You could probably start an instance of Chrome, load the web page and read the entire article in the time it takes Firefox just to start up :)