Author: Eugene Nalimov
Date: 16:32:59 06/27/99
Go up one level in this thread
K6-3 and Celeron are more "Crafty-friendly" than PII/PII and K6-2, as they have full-speed L2 cache, compared to 1/2-CPU-speed for PII/PIII and bus speed (100MHz, and conflicting with main memory traffic) for K6-2. It looks that Crafty cannot fit into 32Kb of L1 cache, but 128Kb of L2 cache (as in Celeron) or 256Kb (as in K6-3) is enough for Crafty to store the most important code and data. When you are moving to 512Kb the additional capacity is not enough to store *all* data (if I remember it correctly, bitboard data structures are huge), and twice less speed is very noticeable. The only better choice (among x86 CPUs) is Xeon, as it has full-speed L2 cache that can be 2Mb in size, and it's bus speed is 100MHz, comparing to 66Mhz for (non-overclocked) Celeron. I suspect that's the main reason for reported behavior. Crafty is much more memory-speed bound than almost any other chess program, so details of CPU microarchitecture is less important than memory bandwith. Eugene On June 27, 1999 at 18:28:25, Larry Applebaum wrote: >On June 27, 1999 at 17:42:45, Frank Quisinsky wrote: > >>Hello, >> >>in the last week I wrote here that Crafty 16.10 (Corbit Version) make 128.000 >>NPS (01. a4 e5, 02. a5 ..., WinBoard 4.0.2, time 40 moves in 40 minutes, 24/8 MB >>for HT, AMD K6-2 400 MHz). >> >>I testet this under the AMD K6-3 450 MHz and see that Crafty 16.10 make 185.000 >>NPS (Celeron 450 MHz (300) make 188.000 NPS, Pentium III 450 MHz make 180.000). >> >>I think for Pentium optimation is this a good result for AMD. >> >>Thanks Bob for Crafty another and thanks Dann. >> >>Dann, you must Crafty optimize for AMD K6-3 not for Pentium :-)) > >Let me toss my two cents worth in here... > >The Microsoft C compilers only optimize with Intel chips as targets >and then only in a general way. The only way I know of to optimize >for AMD chips is hand-crafted assembler. Any other opinions welcome. > >Larry > >> >>Kind regards >>Frank
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.