What is the Flash Player performance bottleneck? Not CPU?

It looks to me that while overall your CPU is, as you put it, barely sweating the probable reason why it is struggling is because the test is fully utilising 1 CPU core and Flash is probably not multi-threaded and cannot use more than 1 CPU for the work that is needed.

If you open up task manager and see that chrome.exe is using 12% of your CPU time which is 1/8 your total CPU power then it is the fact that Flash is not multi-threaded that is the problem.

More CPU cores available does not mean more power is available to any one task, see my answer at How do I calculate clock speed in multi-core processors?

-=EDIT=-

I just tried the test on Firefox and on my quad-core system the cpu usage was at about 48%. I'd assume that it is therefore partially multi-threaded, using a worker (calculation) thread and a rendering thread. I would expect your system to therefore see approximately 23-25% CPU usage on the Chrome.exe process.

Weird, just tried it in Chrome and it is only using the 25% (12% for your system) CPU time I originally expected...

Mokubai

Posted 2011-04-14T05:38:24.433

Reputation: 64 434

Thanks for your post Mokubai. I would have thought that if only one core was being utilised then the usage graph would be high (max?) on one section. Or are the graphs not accurate in that sense? – Simon East – 2011-04-15T00:38:14.507

Also, I tried running the benchmark SWF in the standalone Flash projector (latest 10.2) and the process hovers around 18-22% of total CPU usage during the Ultra test. Perhaps it is using two threads as you said... – Simon East – 2011-04-15T00:53:44.187

1The graphs are not particularly accurate as Windows is in the habit of changing which CPU core is running which task. A program will be rapidly changing where it is running, hence the usage graphs you see. They improved this a bit with Windows 7 and, with games at least, the heaviest working thread gets prioritized onto the first CPU core but there does tend to be a lot of movement. – Mokubai – 2011-04-15T09:06:07.607

Oh OK, I see. Didn't realise that a thread could change cores so frequently, but I suppose it makes sense. So I guess for the best Flash performance you want the fastest CPU clock speed possible, regardless of cores (although Flash might possibly use 2)...? – Simon East – 2011-04-17T11:13:04.210

1are graphics card drivers up to date? – kaykay – 2011-04-14T05:49:53.883

What version of Flash player? – Sathyajith Bhat – 2011-04-14T06:04:44.163

Flash Player 10.2 (latest stable release) and I think I've tried latest ATI Catalyst drivers as well as default Windows 7 drivers, and both seem to offer a similar result. – Simon East – 2011-04-15T01:00:06.743

What is the Flash Player performance bottleneck? Not CPU?

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