High CPU usage with radeon driver.

Ken Moffat zarniwhoop at ntlworld.com
Sun Feb 8 13:26:32 PST 2015

On Tue, Jan 20, 2015 at 11:49:39PM +0000, Ken Moffat wrote:
> On Tue, Jan 20, 2015 at 11:12:20AM +0900, Michel Dänzer wrote:
> > On 20.01.2015 10:46, Ken Moffat wrote:
> > > 
> > >  Anyway, I'd rather have a lower power usage, or more CPU devoted to
> > > what I want to run, but it would be _nice_ to have the correct
> > > driver using less CPU ;)  Any suggestions, please ?
> > 
> > Depending on what you're doing, using glamor instead of EXA might make a
> > difference.
> > 
> > Other than that, it's hard to say much without seeing profiles from
> > sysprof / perf / oprofile corresponding to specific activities.
> > 
>  Thanks for the reply, Michel.  I've spent most of today's computing
> time trying to work out what was causing the llvm problem with sw
> rasterization - turned out that this build of Mesa-10.2.whichever
> did not have some fixes for llvm-3.5.  Now, I've tried Glamor - on
> the plus side, no 'red' in icewm's CPU window.  But on the negative,
> Xorg.bin CPU% remained at around 52% - not the initial high value,
> but not dropping down later, CPU frequencies remained quite
> high / full power, and alt-tabbing between windows, or autorepeat on
> e.g. cursor when typing, was very slow.
>  I'll see if I can get any useful profile information, but if not,
> thanks anyway.
 Took me a long time to get back to this, but I've just upgraded
this system to the current versions of everything in Xorg.  As well
as the 1.17.0 server that includes the 7.5.0 ati driver.  This
64-bit system was still on 7.4.0 and it looks as if I had not
noticed that the 32-bit system was too.

 With glamor, it works well ;)  Thanks for suggesting that.

 Without glamor, Xorg CPU usage was mostly 30-50% of 1 processor.
I did not measure the power.  With glamor, the CPU % is mostly 3-5%
and system power draw is ticking along at 102-105W in a mostly idle
system.  And no red line at the bottom of the icewm cpu window.  All
is good.

Nanny Ogg usually went to bed early. After all, she was an old lady.
Sometimes she went to bed as early as 6 a.m.

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