Author: Dann Corbit
Date: 14:37:28 06/02/99
Go up one level in this thread
On June 01, 1999 at 21:36:15, Dave Gomboc wrote: >On June 01, 1999 at 21:13:28, Jeremiah Penery wrote: > >>It crashes because you don't have the book files. If you have them, it doesn't >>crash. :) I removed them from my system, and mine does not crash. >I have them, I just had books.bin renamed to books.bin.old, and had read-only on >book.bin so I wouldn't blow it away by accident. :-) Thanks! (But why does the >bench depend on these being present? Yuck!) > >First block is for Dann's latest 16.8 exe on his site (mt=2): > >Total Nodes: 66918014 >Raw nodes per second: 264205 >C.A.P. ratio: 3.302571 >SMP time-to-ply measurement: 3.666667 > >This is for the non-multiprocessor version: > >Total Nodes: 59979081 >Raw nodes per second: 166696 >C.A.P. ratio: 2.083707 >SMP time-to-ply measurement: 5.202899 > >Especially the last item is a bit puzzling, because this is a single-cpu version >of Crafty. Dann? > >The speedup from 1 to 2 processors on whatever position(s) are searched in >"bench" is 1.585, this sounds pretty low to me... The mt version is compiled with /MT, which slows down the code a lot. The single threaded version is much faster with a single cpu than the multi-threaded version. Probably a lot of lazy use of semaphores and critical sections on gated statics or something like that. There really should not be such a huge difference, but there is.
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.