Slow poor performance - working set question

User Help for Mozilla Firefox
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Joined: June 11th, 2006, 7:29 pm
Location: New Hampshire, I think

Post Posted November 10th, 2016, 9:39 pm

Using Windows 7 Home Premium SP1
Firefox 49.0.1

I have 12 tabs.
Working set is 1.3 G.
Page fault delta runs between 500 and 6,000 per second, mostly around 1,000 / sec.
Physical memory is 6 G. Task Manager shows 3.5 G in use.
Firefox CPU is running 20% - 40%, mostly around 25%.
There is almost no net traffic.

Response is slow - 1/2 to 1 second scroll-bar response time, sometimes 1.5 second

Is there some Firefox or Windows number I need to adjust?


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Post Posted November 11th, 2016, 6:12 am

Have you tried starting Firefox in Mozilla Safe Mode?
If no improvement using Safe Mode, do you have the same problem if you create a new profile and test it with no extensions or non-default themes installed?
and ... on_Windows

Also see


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Post Posted November 11th, 2016, 10:23 am

(I don't know what "page fault" is, otherwise...)

I'd think it more a CPU issue rather then RAM.
See if you can figure what is using 25%, constantly?

Maybe some Flash ads (or even now, HTML5 ads) in one of your windows?
Might try an ad blocker?
Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv: Gecko/20110420 SeaMonkey/2.0.14 Pinball CopyURL+ FetchTextURL FlashGot NoScript

Posts: 54
Joined: June 11th, 2006, 7:29 pm
Location: New Hampshire, I think

Post Posted November 11th, 2016, 3:13 pm

Thanks all!
In safe mode, performance is better.
I'm looking for which add-ons get in the way. It's a bit challenging, because of a sort of hysteresis in reaction. Good performance in safe mode, slow in non-safe, still slow after I disable extensions.
I've tried with Adblock Plus enabled and disabled. Also Avast Online Security.
Killing tabs reduces load uniformly, i.e. no particular tab is responsible, that I can find so far.
I'll keep plugging.

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