why does hardware acceleration mode make firefox so slow?

[LAMj]

I tried Firefox HA mode and it just make Firefox dramatically slowed down. The UI rendering is so laggy and the web rendering of youtube when scrolling is considerable laggy too. Firefox renders and scrolls youtube fine when HA is off. IE9 renders youtube normally so can anyone explain the reason Firefox is so horrible at it? Or why bother with HA at all if it doesn't actually render Firefox faster?

[Nylonee]

I had a similar problem after updating my flash player to 64bit. I'm assuming it's just configured to different platforms and works differently accordingly. Never really investigated though. Anybody else?

[+Zlip792 MVC]

Well, it might be due to several reason, I personally also victim of it so I am not gonna defend Firefox but you can do several things to reduce impact of Hardware Acceleration.

1) Update your driver

2) Tweaking settings in about:config

Also can you tell me your addons list, might be some addon making your UI so slow. Firefox improved a lot since FF7 onward. FF13 is quite snappier than any earlier version.

[LAMj]

Well, it might be due to several reason, I personally also victim of it so I am not gonna defend Firefox but you can do several things to reduce impact of Hardware Acceleration.

1) Update your driver

2) Tweaking settings in about:config

Also can you tell me your addons list, might be some addon making your UI so slow. Firefox improved a lot since FF7 onward. FF13 is quite snappier than any earlier version.

My addons are of the usual ones like adblockplus, greasemonkey,firebug,flashgot,User Style Manager, etc. I set my graphic driver to be updated automatically so it shouldn't be a problem. Firefox feels pretty snappy with HA off, so it must be their HA mode that slow it down.

What setting are you refering to in the config?

[Athlonite]

It's because FF HA mode is still young and hasn't matured hence why software mode works much better they've done all they can to make it fast and stable now it's time to try using something other than the CPU alot of browsers that are starting out with GPU acceleration are having problems with either speed or stability or both and like anything new it takes time to become good

[The_Decryptor Veteran]

What hardware are you running and what version of the drivers are you using? Certain cards/drivers have random bugs that Firefox can hit which either slow it down or crash (or cause invalidation issues, etc.)

[LAMj]

I'm running a laptop with C2D T9300 and Nvidia 8600M GS with latest driver 296.10.

[+Zlip792 MVC]

I'm running a laptop with C2D T9300 and Nvidia 8600M GS with latest driver 296.10.

Today there are chances of new driver release, so make sure to update. I personally had issues with 296.10 so I am using currently 301.40 and it is much better than 296.10. Also new driver will be from same branch as 301.40.

Also should I suggest you once try Nightly for a while and tell us whether you feel any difference?

[LAMj]

I was reading the Opera release thread and apparently they are offering both OpenGL and DirectX options. Is it posible that Mozilla could do the same? DirectX seems to be superior at doing HA in IE9 compare to OpenGL in Firefox. Does anyone have a lead on Mozilla HA's developement?

[The_Decryptor Veteran]

Firefox's hardware acceleration already uses DirectX (Has since 4.0), OpenGL isn't used by default because a bunch of cheap cards have either terrible or no support for it.

I've got a GTX 570 with full OpenGL support for the latest version, but Firefox still doesn't use it.

[ArialBlue]

Firefox HWA is terrible because, (research! "lurksearch" {tm})

1. Developers focus on Smart Phone Version
   
2. Developers focus on Panorama, Smooth WebM playback and other things of little value.
   
3. Developers do not have any way to test D3D10 performance for some reason, otherwise they would know it is slow.
   
4. Most Developers use Macs.
   
5. Aside from a developer called Bas, I don't know anyone who talks about Windows HWA.
   
6. Developer's solution to Windows HWA problems is a BLACKLIST.
   
7. Last performance improvement for HWA was Azure in FF7 which does NOTHING for helping YouTube, tab scrolling, etc.
   
8. I also heard that a lot of rendering that is supposed to be accelerated falls back to software for GUI.
   
9. They probably just don't care.
   

[+Zlip792 MVC]

I was reading the Opera release thread and apparently they are offering both OpenGL and DirectX options. Is it posible that Mozilla could do the same? DirectX seems to be superior at doing HA in IE9 compare to OpenGL in Firefox. Does anyone have a lead on Mozilla HA's developement?

Well, Firefox already offer both Hardware Acceleration but Skia backend (OpenGL) can only turned on for canvas hardware acceleration. Azure Content Acceleration will be Nightly (FF15) turned, which is better than Cairo backend but it still uses Cairo as a backend but it is still better.

[Chrysalis]

Firefox HWA is terrible because, (research! "lurksearch" {tm})

1. Developers focus on Smart Phone Version
   
2. Developers focus on Panorama, Smooth WebM playback and other things of little value.
   
3. Developers do not have any way to test D3D10 performance for some reason, otherwise they would know it is slow.
   
4. Most Developers use Macs.
   
5. Aside from a developer called Bas, I don't know anyone who talks about Windows HWA.
   
6. Developer's solution to Windows HWA problems is a BLACKLIST.
   
7. Last performance improvement for HWA was Azure in FF7 which does NOTHING for helping YouTube, tab scrolling, etc.
   
8. I also heard that a lot of rendering that is supposed to be accelerated falls back to software for GUI.
   
9. They probably just don't care.
   

I agree, when I used firefox on a linux recovery disk, it runs so much smoother than the windows version.Also firefox has a page where they classify the various versions, the classification affects how much dev focus it gets. Its notable that the windows version of firefox is not in the top classification.Trying to find the url now with the info but I found this out when looking for why is no 64bit windows version and then discovered because they dont treat windows as that important.Its sad but they consider mobile platforms and even metro as more important than 64bit windows desktop version.http://www.computerworld.com/s/article/9234997/Mozilla_compromises_on_x64_Firefox_after_user_backlashLinux and even mac os (a OS I consider irrelevant on desktop) have 64bit firefox. For whatever reason firefox dev's treat windows as a 2nd class OS.Firefox is probably my most power hungry app, it draws mroe resources from my PC than even some games, right now its using 1.1gig of ram and a 32bit version can only address 2 gig. It also crashes often and slows down a lot, I remain curious if these issues would be resolved with a 64bit version, as now days a browser is not just for web pages, its used as a launcher for apps and multimedia.On the Hw acceleration this is highlighted a lot.Firefox 3 using software rendering runs very smooth, but of course it doesnt support many of today's modern web features. However if disabling hw acceleration in firefox 20 (or any new version) the software mode is slower than it was in firefox 3's day because it now has no focus on it plus features are been added that bog it down. Hardware mode is smooth if the 3d card is moderatly powerful and isnt throttled back. using firefox puts a lot of load on my nvidia card, it hits high temperatures and is often on 3d clocks, it I use an app to force the card to stay in 2d idle mode (which Ie can handle) firefox becomes jerk city, it struggles to even scroll pages like neowin forums. It is extremely power hungry and clearly not very optimised.See this alsohttp://arstechnica.com/information-technology/2012/11/64-bit-firefox-for-windows-should-be-prioritized-not-suspended/Here is the link for dev priority, found it. Windows 64 tier 3. linux 64 tier 1.https://developer.mozilla.org/en-US/docs/Supported_build_configurations