Firefox and chrome chewing CPU since updates

[Peter Teuben]

On 07/01/2012 01:32 AM, 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.
>
>

I find that chrome is also often eating a lot of my CPU cycles (talk 
about green computing!),
but more than often it's because certain tabs that I have open use flash 
or some other
method to chew away at the CPU. If you open chrome on a simple html page 
that doesn't do flashy
things, you should find it to be much much better behaving.

Another CPU black hole is thunderbird, not because it's thunderbird, but 
if you have
several accounts and tag them to check your account(s), there is going 
to be a lot of
IO on small files. that's a killer for your CPU as the I/O will block 
your CPU.

I also found picasa to be pretty bad, as this can also be configured to 
pay attention to
your disk (for new files).   dropbox is another potential client for 
this. All in all, with our
modern desktops that watch out for us, it kills performance. I used to 
be able to
compile a particular package i develop in 3 minutes, now i wait for 8 
minutes till it's done.

One task I found useful to run (apart from xload) is iotop (you need to 
be root for this),
maybe there are other good programs for this, but you'd be surprised.

One thing I've now had several times is that for totally unclear reasons 
the load on my
system climbs to well over 10,and for several minutes I loose complete 
control of the
desktop. The mouse will generally move, but it won't change focus or 
allow me to do anything.
Extremely frustrating.  By several times I'd say this is once or twice a 
week.


peter