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Re: multi cpus

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William Unruh wrote on 28. February 2015:
>
> On 2015-02-28, john@wexfordpress.com <john@wexfordpress.com> wrote:
>> My computer seems to bog down on certain apps like scribus, swriter etc. Yet when 
>> I check "top" the app in question is using 100% of the cpu. In fact I have three cpus. Is it possible that only one is being used? If so, how do I fix this? 
>> Slackware 14.1.
>
> Most programs can use only one cpu. They are not designed for parallel
> operation.

While some claim they can but don't.

Like the MESS emulator (part of MAME) here. Although I cannot see in the
verbose output whether or not it uses multi-treading, I am sure I compiled
it in. But that is what top tells me about my CPU (2 core AMD):

%Cpu0  : 22.0 us,  6.3 sy, 11.3 ni, 59.3 id,  0.0 wa,  0.0 hi,  1.0 si, 0.0 st
%Cpu1  : 99.7 us,  0.0 sy,  0.0 ni,  0.0 id,  0.0 wa,  0.0 hi,  0.3 si, 0.0 st

  PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+
  COMMAND
16625 user    20   0  424788 295956  33996 R 103.1  7.9   1:20.34 mess.comp

So one core is 0.0 idle, while the other is doing some other things I
have running. If those things wouldn't run now I would have close to
100 idle on the other core: one is working like a slave, the other is doing
nothing.

The mess.comp process uses 103% on ONE core instead of 100%.

Anyway, MESS itself runs very slow, skips 10 frames (that's the maximum I
allow) while running the emulated system (I just tried a Sharp X68000
from 1987) on 30%. I know that even if both CPU cores would be available
for 100% I couldn't get 100% speed for this system. And even if I just
emulate the Nintendo Entertainment System (came to the US in 1985) I
barely just have about 100% speed with no frame skip.
-- 
Andreas

I wish my grass was emo. Then it would cut itself.

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multi cpus "john@wexfordpress.com" <john@wexfordpress.com> - 2015-02-28 06:01 -0800
  Re: multi cpus Pascal Hambourg <boite-a-spam@plouf.fr.eu.org> - 2015-02-28 15:15 +0100
    Re: multi cpus Robert Heller <heller@deepsoft.com> - 2015-02-28 08:52 -0600
    Re: multi cpus Baho Utot <baho-utot@columbus.rr.com> - 2015-02-28 15:51 -0500
  Re: multi cpus Tim Watts <tw_usenet@dionic.net> - 2015-02-28 14:51 +0000
  Re: multi cpus William Unruh <unruh@invalid.ca> - 2015-02-28 18:31 +0000
    Re: multi cpus Robert Heller <heller@deepsoft.com> - 2015-02-28 13:11 -0600
      Re: multi cpus Bobbie Sellers <bliss-sf4ever@dslextreme.com> - 2015-02-28 13:35 -0800
    Re: multi cpus Andreas Kohlbach <feb15.5.ankman@spamgourmet.net> - 2015-02-28 16:31 -0500
    Re: multi cpus Jean-David Beyer <jeandavid8@verizon.net> - 2015-03-05 21:11 -0500
  Re: multi cpus faeychild <faeychild@nomail.afraid.org> - 2015-03-01 12:32 +1100

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