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Date: Mon, 14 Jun 2010 17:46:46 -0400
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To: Dave Airlie <airlied@gmail.com>, Dave Airlie <airlied@redhat.com>,
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Subject: Re: Why is kslowd accumulating so much CPU time?
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On Mon, Jun 14, 2010 at 02:42:44PM -0400, Nick Bowler wrote:
> 
> This sounds exactly like the issue I've been seeing on a T500 laptop, as
> well (GM45 board).  The slowdowns render the system essentially
> unusable, as it can spend a loooong time just moving the mouse cursor a
> few pixels on the screen.  During this time, nothing else on the display
> is updating (glxgears drops to 0fps).  Things generally seem to be
> working fine if I am not moving the mouse, or if I'm not running X.

I saw exactly the same behaviour when using the Ubuntu Karmic
userspace.  Basically, using a 2.6.35-rc2 (+ vt memory corrupter fix)
kernel, the system was essentially unusable.  Interestingly, the
problem went away (with the same kernel) once I updated to Ubuntu
Lucid.  I was going to mention that so that hopefully someone with far
more X.org-fu than I could figure out how much of this is a X server
bug, and how much of this was a kernel bug, but things worked just
*fine* with 2.6.34 kernel.

Occasionally it will happen that the mouse stops tracking, and then I
grumble and curse, and a few seconds later it resolves itself.  I
haven't had time to track it down; but the problem was breathtakingly
easy to reproduce with an Ubuntu Karmic userspace.  :-)

     		       	  	 		    - Ted
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