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Up Topic Rybka Support & Discussion / Rybka Discussion / Rybka Mp-scaling implementation
- - By urodets (**) Date 2009-08-14 07:53
I'd like to know how Rybka multiprocessor support works. I  using Linux, so my Rybka is microwined. In task manager I can see a PID's used by Rybka, for example:
PID   USER  PRI NI   VIRT        RES   SCH S CPU% MEM%  TIME+     Command
5064 root   20    0  2151     75532   416  R  100    1.9      28:44.11  /proc/self/exe microwine-internal.exe 5059 4 2048 1 4 1 5059
5065 root   20    0  2151     75692   432  R   99.9  1.9      28:23.23  /proc/self/exe microwine-internal.exe 5059 4 2048 1 4 3 5059
5063 root   20    0  2151     75556   416  R   100   1.9      31:08.41  /proc/self/exe microwine-internal.exe 5059 4 2048 1 4 2 5059
5059 root   20    0  2151     75544   416  R   99.9  1.9      26:31.20  /home/oleg/Rybka3-native

CPU  usage is never getting 100% by all PID's and exchanging between them (100 99.9 99.9 100   99.99 99.9 100 100  and so on).
I tried to change AFFINITY MASK by taskset and get every process running only by one core:
taskset -p 00 5064
taskset -p 01 5065
taskset -p 02 5063
taskset -p 03 5059 ,
where 00, 01 -CPU-cores, respectively.This result in that only 3 cores is used, and one is 0%. changing  AFFINTY MASK to f (all PID's are running by all 4 cores) changing back to 100%. Just curios how the mp support works in Rybka.
Parent - By Vempele (Silver) Date 2009-08-14 08:46 Edited 2009-08-14 09:03

> MASK


You keep using that word. I don't think it means what you think it means.

> taskset -p 00 5064


Setting the affinity mask to NO CPU. Shouldn't there be an error?

>taskset -p 03 5059


Processors #0 and #1.

In conclusion, RTFM. Also, why are you using octal?
- - By urodets (**) Date 2009-08-14 11:23 Edited 2009-08-14 11:26
Yes, you are right i didn't get it right, affinity mask is the bit mask for cpu in hexadecimal. What I want to test is to set single PID to a core1, 2ndRybka PID to core2 and so on.
Parent - - By Vempele (Silver) Date 2009-08-14 12:59
taskset -p 5064 -c 0, I think.
Parent - - By urodets (**) Date 2009-08-14 14:02
does`nt work, I getting
execvp: No such file or directory
failed to execute -c
Parent - - By Vempele (Silver) Date 2009-08-14 14:10
Oops, taskset -cp <core> <pid>
Parent - By urodets (**) Date 2009-08-14 14:27
yes, I figured that, thx.
Up Topic Rybka Support & Discussion / Rybka Discussion / Rybka Mp-scaling implementation

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