Page 1 of 1

"1 core" issue with stockfish 171

Posted: Sun Jun 20, 2010 2:24 am
by JCoit
I'm running Ubuntu 10.04 LTS 64-bit, running Stockfish 1.7.1 JA with xboard and polyglot on an AMD Phenom x4 (quad core cpu). I've specified 4 threads in the ini file that polyglot uses, but Stockfish does not use 4 cores. All other behavior is normal, logs on to FICS, uses the book, wins a lot, etc. Has anyone else experienced this? I watch it using 'top' in the terminal, and also suspected it before verifying it with top because it does not search as deeply as it was on my other, slower, 32-bit windows machine. Sure enough, only 1 core and I can't get it to use any more.

I'll also warn, I'm no linux guru, so maybe I have a system setting incorrect... any ideas on that?

Re: "1 core" issue with stockfish 171

Posted: Sun Jun 20, 2010 6:19 am
by Michel Van den Bergh
Xboard overrides the polyglot.ini file settings for threads. You should specify the number of threads on the command line
with -smpCores.

You can also use the global/engine configuration dialog in the menu to set options.

If you do this there is no need to invoke polyglot directly. You can simply do

xboard -fcp <path to stockfish JA> -fUCI