CPU spikes & jerky playback of audio or video content

[Tbird761]

I've been having a problem with the flash plugin this year.  I'm not sure when it started exactly, but I'm certain that this wasn't happening during 2011.

When at a site that uses Flash for video+audio (Youtube and similar) or even audio-only playback (Turntable, Pandora, etc), I find that the flash plugin causes spikes of 100% CPU usage (on one core) and that the video or audio will pause for a moment during those spikes.  The disruption is typically in the 100-500ms range.

Frequency of the spikes seems to vary over time.  It's fairly typical to experience a situation where it starts off bad and the frequency of disruption lessens over the course of 30 minutes until there are no disruptions at all.  If you keep using playback, it'll work its way into being bad again.  You're likely to start using the flash plugin at any point on that sine wave of disruption intensity.  It might start working well but slowly get worse, it might start bad and slowly get better, it might start at a tolerable level and work its way worse or better depending on if you're on the rising or falling side of the cycle.

Whatever it is, it isn't my Windows install.  I switched from an AMD FX-8120 to an Intel 3930K about a month ago and this problem persisted through new hardware and a fresh install of Windows using the latest device drivers for everything.  I've even tested different browsers in case it was an issue with only the non-IE plugin or with my specific browser (Opera).  The issue happens in Chrome, IE9, Opera, and FF on my system.  I've also tested both with and without hardware acceleration, but there is no difference.

I have to wonder if there are any known issues with particular sound cards (Xonar STX), unusual video configurations (dual Radeon 6970s in crossfire), or peripherals.  Perhaps with output sampling rates (96 KHz) or security software like MSE?

Anyhow, I mention this here in the hope of either raising awareness of a problem or finding answers if this is a known issue.  It's silly that playing back audio would be a challenge in 2012 with good equipment.  There is sure to be a logical explanation that can help lead me to a resolution.  Thank you.

[chris.campbell]

You definitely have a system that should be able to handle simple video.  Could you try disabling hardware acceleration to see if we can start narrowing down possibilities?

How do I disable or enable hardware acceleration?

[Tbird761]

Hello; it's good to hear from you.  I did try hardware acceleration on and off and found the problem to be present in both cases.

[chris.campbell]

Ok, next let's test out both of these videos.  Do you see performance issues with either one?

Test 1

Test 2

[Tbird761]

Everything is behaving tonight, but as I mentioned the problem comes and goes.  It's also worth noting that the HTML5 link didn't seem to trigger Youtube to send a page with an HTML5 video tag.  I still ended up with Flash.

[chris.campbell]

Interesting, what browser were you using when the html5 player reverted to Flash?

[Tbird761]

I was using Opera 11.64.

[Guest]

Hey Tbird, I was asking the guys about this jerky playback bug here:

https://bugbase.adobe.com/index.cfm?event=bug&id=3155813

It turns out this problem is very likely found in mainly computers with single-core CPUs or low-power mutiple-core CPUs. What type of CPU model is on your computer?

My advice to everyone who has this jerky or choppy or stuttering playback on Flash Player 11.2 is to downgrade back to Flash Player 11.1 for now until the Adobe guys can fix this problem which seems to be with the multi-threaded decoding engine introduced in Flash Player 11.1. Make sure you uninstall Flash Player 11.2 completely before installing Flash Player 11.1.

You can get Flash Player 11.1 in this zip file archive from the link below. Just make sure you look for the right setup folder with the right setup program file in zip file archive  (For example, if you got Windows 64-bit OS, then look for win64 (or x64 for windows ). If you got windows 32-bit OS, then look for win32 (or x86 for windows)

http://fpdownload.macromedia.com/get/flashplayer/installers/archive/fp_11.1.102.63_archive.zip

[Tbird761]

Thank you for commenting, hikerKS.  In my particular case I'm using an Intel Core i7-3930K.  It's a 6-core CPU so that shouldn't be an issue in my case, but perhaps others may benefit.

[Guest]

hmm, see if you can look into your BIOS settings on your computer motherboard and see if there's a way to disable certain cores. If not, then that's fine. Well, threaded programming involves multiple processes working and sharing data simultaneously and synchronized at work as one process which one of the most difficult and trickiest types of programming. So far, it seems Flash Player 11.2's multi-threaded decoding engine works well in 2-core cpus. According the specs of your CPU, Core i7-3930K has 6-cores, but can run 12 thread processes at the same time. Since the thread processes in the multi-threaded decoding engine doesn't work well with 1 single core CPU, especially with the Intel CPU's hyper-threading technology, then the thread processes from the decoding engine is not working very well simultaneously being segmented across 6 cores and with the 12 thread processes created by hyper-threading technology segmenting the code and may be creating conflicts with the thread processes already designed into the flash player 11.2's multi-threaded decoding engine. Basically, flash player 11.2's video decoding engine is making thread processes, and your Intel CPU hyper-threading technology hardware is adding more thread processes on top of the original thread processes making the synchronicity of the flash player's thread processes put out of sync.

Oh yeah, if you get to the BIOS settings, TBird, see if you can disable hyper-threading technology for your CPU which might help.

[Tbird761]

Last night flash playback was being choppy again even though the first time I responded it was behaving.  It was doing that 100% CPU spike thing every second or so while watching an Amazon streaming video.

[Guest]

Tbird, out of curiosity, did you try what I suggested, which was disabling the hyper-threading technology for the CPU in the BIOS settings of your computer, and then test flash player 11.2 to see what happens because you could report this by adding notes on the bug report on the link below: By the way, keep an eye on this bug thread, because the developers of flash said they might have a fix for this problem with a new public test build. So keep an eye out on this bug report for possible updates: https://bugbase.adobe.com/index.cfm?event=bug&id=3155813

[hkudo]

Tbird,

I  am curious your test result with disabling hyper-threading as hikerKS asking above. Please try it out and let us know how it looks.

thanks,

Hitomi

[Tbird761]

I can disable HT as a diagnostic, but turning off one of the primary performance features of my CPU is hardly a solution.

[hkudo]

Yes, I know it won't be a solution but it will help us to know if this issue is related to CPU HT feature or not. Flash Player team couldn't have reproduced this problem internally so we appreciate your help very much.

thanks,

Hitomi

[Tbird761]

HT has been disabled.  Time will tell. 

[Guest]

TBird, they don't want you to just only disable HT. After disabling HT, they want you to also test the Flash Player 11.2 by playing flash videos on it to see if the HT in your CPU causes conflict with the video decoding engine in Flash Player 11.2. In other words, TBird, you managed to reproduce a software bug the Adobe people couldn't reproduce, and they want your test results from the video playback on your computer to give to the Adobe Flash Player software developers to analyze it, investigate the source of the software bug and hopefully fix it.

[Tbird761]

Please remember that my issue comes and goes.  I can't simply play the videos any time I want and see if the problem is gone.  I say time will tell because I quite honestly have to wait and see if I notice the issue happening again.  If/when I do, I'll run the test videos.

I'll also point out that my original post mentions that I first experienced this issue on an AMD FX-8120.  Being an AMD processor, it of course doesn't have HT.

[Guest]

You're right. There is no Intel hyper-threading technology in AMD processors, but hyper-threading (or HT) is just a name for Intel's multi-threading technology. The main problem being investigated is if these CPUs (especially CPUs with multi-threading technology hardware) conflicts with the multi-threaded processes in Flash Player 11.2's multi-threaded video decoding engine. Your AMD FX-8120 processor actually has multi-threading technology when I looked at the specs, and so in your AMD FX-8120 computer, disable anything in the MD FX-8120 computer's BIOS that says threading or multi-threading or CMT (AMD's abbreviation for their Clustered-based Multithreading Technology) or Clustered-based Multithreading Technology. Then try testing the videos again on your AMD computer.

[Guest]

Hello forum,

Chris Campbell can you please tell me what is the difference of the two test videos. The "test 1" video is choppy and cpu spikes to 100% while the test 2 plays fine. Thank you.

[Guest]

if you look carefully at the link for the "test 1" video, it says html5 and when you click on that link and right-click on the video, there's a menu that pops up for html5 player. Basically, the "test 1" video is not using the Adobe Flash player, but Youtube's own video player programmed with html5 technology. So "test 1" is using html5 and no flash player, and test 2 video uses flash player. That's why the "test 1" video is choppy which means you're gonna have to talk to youtube.com to fix that choppy playback issue on the youtube's own html5 player. In the meantime, you can just change the url for the "test 1" video by removing the segment "&html5=True" to play "test 1" video with Flash Player.