We regularly get threads on Flash's performance and stability issues. I've written a blog entry to document the current state and workarounds.

http://duganchen.ca/3d-accelerated-w...dia-and-issues

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Also, VDPAU is only in the 32bit plugin (AFIAK).

My girlfriend plays a crap-ton of Facebook flash games. With acceleration enabled, they always had the overlay bug (Flash image remains on screen even after the webpage is closed). I'll have her give the VDPAU_NVIDIA_NO_OVERLAY=1 a shot.

The 32-bit and 64-bit versions are identical. I can confirm that VDPAU is also in the 64-bit version.

The VDPAU_NO_OVERLAY setting does make things a lot more stable for me.

Also, do make sure that you're running the latest nvidia drivers (280.13 as of this writing). Flash seems to be a large source of Nvidia's bug reports.

I've never had an issue with Flash and the Nvidia drivers (using the last build posted at SBo).

I did install libvdpau prior to installing my drivers and I do have vdpau-video installed with all dependencies as well.

But yeah, I play the Flash games too on Facebook and I have never had issues.

And then you turn never turned on 3D acceleration in Flash. Which is why you never had issues.

Flash's default setup is stable no matter which video drivers you're using (people here have reported crashes with the latest kernels though). It just doesn't perform that well. It's when you enable the disabled-by-default video acceleration feature that you start running into crash bugs.

So far I haven't had any crashes (flash 11, nvidia-280.13) but the acceleration leaves much to be desired. On my AMD X2 2.4Ghz dual core, can watch 1080p flash movie full screen at around 40-50% utilization on both cores via Firefox-5.01, with acceleration turn on that drops to about 25-35% on both cores. If I d/l the flash video file and play in through vdpau on mplayer/gnome-mplayer, I get 20-30% on one core. Also, haven't needed the no overlay setting yet.

No, I have it enabled. No problems.

Athlon II X3 425 here. Flash 11.0.1.152 with the NVidia Drivers 290.10. And all hacks (e.g. VDPAU_NO_OVERLAY) turned off.

Even with 3D acceleration turned on, I can't watch a 720p Crunchyroll video full-screen (or even in a larger window) without the video becoming noticeably jerky. With the video in a normal-sized window embedded in the page, it plays at normal speed. But with a CPU utilization of 43%! (And no, CPU frequency scaling isn't turned on).

This level of performance is completely ridiculous!

I'm going to wait for 11.2 (which has multithreaded decoding) to become stable. If even that doesn't improve things, then I might end up buying a new CPU and motherboard just to watch streaming videos.