Firefox and chrome chewing CPU since updates

[Nataraj]

On 07/01/2012 12:33 AM, Nataraj wrote:
> On 06/30/2012 10:32 PM, Paul Smith wrote:
>> So, I was away all week on vacation (during that time my system was
>> halted and unplugged) and when I got back I had 56 or so updates waiting
>> for me (Ubuntu 12.04 64bit) including a kernel update and various other
>> things.
>>
>> I applied these and rebooted.  Now whenever I start a browser, either
>> the default Firefox or Chrome (I use the main/stable version from the
>> dl.google.com repository), it sucks up TONS of CPU.
>>
>> Firefox is usually chewing at least 60% CPU and sometimes jumps to 120%
>> or more (I have an Intel Core2 Quad).  top(1) says my system load is
>> constantly at 1.3 or above.  This is with no extra tabs open and
>> about:blank on the single tab I do have.
>>
>> Chrome is even worse, since it's multi-processing: when I start it there
>> are 3 to 4 chrome processes running each taking between 25% and 45% of a
>> CPU, and my system load goes up to 2.2 or higher, constantly.
>>
>> The browsers seem to WORK just fine; I can surf the web and no problems
>> with internet connections, etc.  Just my system is running like crazy,
>> not doing anything.
>>
>> This was never a problem before these updates.  Has anyone else seen
>> this, or have any idea what's going on?  It's very odd that it's both
>> Firefox and Chrome, I admit, but if I stop them the load goes down and
>> none of my other apps (which, admittedly, I don't use too many different
>> apps--mostly Emacs, rxvt, Evolution, etc.) seem to show this problem.
>>
>> Has anyone else seen this behavior?  I've tried strace on these but see
>> nothing interesting: chrome seems to be hanging on a futex (but not fast
>> enough for the kind of load I'm seeing) and Firefox seems to be failing
>> to read from a socket (but again, not fast enough for the load).
>>
>> This is extremely frustrating.
>>
>>
> Yes.  I saw the same behavior with 10.04.   Chromium, firefox and
> thunderbird were all affected.  I rebooted a second time and the
> situation seems to have improved.  I'm unsure yet whether there is still
> a problem.  It seems that it was either the kernel or the microcode
> update that caused the problem.
>
> Nataraj
>

Maybe this was caused by the leap second issue.  See
http://www.google.com/search?ix=acb&sourceid=chrome&client=ubuntu&channel=cs&ie=UTF-8&q=leap+second+linux

Nataraj