what on earth is firefox up to?

[jdow]

On 2012/07/01 00:27, JD wrote:
> On 07/01/2012 12:39 AM, jdow wrote:
>> On 2012/06/30 20:55, JD wrote:
>>> On 06/30/2012 08:17 PM, Tom Horsley wrote:
>>>> Every time I start firefox after recent updates, top
>>>> shows it periodically taking up to 50% of the CPU
>>>> even if I'm just looking at a simple page of plain
>>>> html (no scripts, not even any images) on my local
>>>> web server.
>>>>
>>>> This is ff 13.0.1 on x86_64 fedora 17.
>>>>
>>>> Any clues? Anyone see anything similar?
>>> 50% !!!???
>>> Huh.... consider yourself LUCKY!
>>> On my old unicore amd64 (3.7GHz "equivalent :) :) /smirk/)
>>> it escalates  sometimes to 95% of cpu.
>>
>> top tends to be confusing that way.
>> Note this line from my machine at a time it said FF was at 87.8%:
>> Cpu(s): 13.6%us, 33.7%sy,  0.0%ni, 52.5%id,  0.0%wa,  0.0%hi, 0.2%si, 0.0%st
>>
>> That was really 87.4% of the 13.6% user time that was consumed.
>>
>> {^_^}
> in <kernel source>/include/linux/taskstats.h
> The comment reads:
>          /* cpu "virtual" running time
>           * Uses time intervals seen by the kernel i.e. no adjustment
>           * for kernel's involuntary waits due to virtualization.
>           * Value is cumulative, in nanoseconds, without a corresponding count
>           * and wraps around to zero silently on overflow
>           */

Hm, please define virtualization in this context. I am running a flat
SL6.2 system with no virtual machine in the box at all.

Note that you get 100% if you add up all the values on that line.
There is no way you can get 87.4% cpu usage out of those numbers
without claiming some of the idle time is used by firefox without
attribution.

{^_^}