Author: Robert Hyatt
Date: 20:24:23 06/19/02
Go up one level in this thread
On June 19, 2002 at 22:03:07, Brian Richardson wrote: >On June 19, 2002 at 13:08:21, Robert Hyatt wrote: > >>On June 19, 2002 at 10:30:39, Brian Richardson wrote: >> >>>On June 19, 2002 at 00:39:23, Robert Hyatt wrote: >>>>Two points: >>>> >>>>1. The 21264 runs Crafty at > 800K nodes per second using a single processor >>>>at 600mhz. What 32 bit single processor can run crafty that fast? Answer: >>>>zero. >>>> >>> >>>Actually, my AMD 1900MP runs Crafty slightly faster than both the single and 2 >>>cpu Alpha WAC nps test results, albeit at about 1600MHz, not 600. >>> >>>Of course, just having 64bits is not enough. MIPS was 64 bits in Oct 1991, but >>>broad industry support requires other things, like lots of software, etc. >>>Otherwise, Digital might have bought Compaq. >>> >>>That said, I decided to use 64 bit bitboards in Tinker (baed on Crafty) 4 years >>>ago in anticipation of 64 bit Intel processors. I did not figure that Intel >>>would be several years late. >>> >>>Brian >> >> >>Your single-cpu machine breaks 1.2M nodes per second? I haven't seen such >>results from any machine I have run on (32 bit machines anyway, limited to a >>single CPU)... > >I can only go on what you posted earlier, Bob. Nearly 800Knps was the single >cpu system. Either way, the AMD is slightly faster, as I had emailed you >earlier. Note that this was also with v16.19 (no lockless hashing factor). > >Alpha >1 cpu 21264/600mhz: >total positions searched.......... 300 >number right...................... 300 >number wrong...................... 0 >percentage right.................. 100 >percentage wrong.................. 0 >total nodes searched.............. 236973211.0 >average search depth.............. 4.5 >nodes per second.................. 783641 > >2 cpus, 21264/600mhz: >total positions searched.......... 300 >number right...................... 300 >number wrong...................... 0 >percentage right.................. 100 >percentage wrong.................. 0 >total nodes searched.............. 330905102.0 >average search depth.............. 4.5 >nodes per second.................. 1266767 > >AMD 1900+MP >max threads set to 2 >hash table memory = 384M bytes. >pawn hash table memory = 32M bytes. >pondering disabled. >Crafty v16.19 (2 cpus) >test results summary: >total positions searched.......... 300 >number right...................... 300 >number wrong...................... 0 >percentage right.................. 100 >percentage wrong.................. 0 >total nodes searched.............. 19013488028.0 >average search depth.............. 12.2 >nodes per second.................. 1357144 >(run without test xxx n, st=60) > >1 CPU >total positions searched.......... 300 >number right...................... 300 >number wrong...................... 0 >percentage right.................. 100 >percentage wrong.................. 0 >total nodes searched..............4639292700.0 >average search depth.............. 9.7 >nodes per second.................. 960490 >(run with test xxx n=8) I am _totally_ confused now. The alpha did 800K with 1 cpu, 1200K with two. We discovered the "locking" problem and eliminated it, which made the NPS scale like it should later. The 2 cpu = 1.5x faster was a clue in that NPS (for crafty) scales linearly with number of processors, although search overhead makes some of that NPS wasted. For your results, your 1 cpu number is 960K and your two cpu result is 1300K. That doesn't look reasonable. And AMD dual should see the NPS almost exactly double using two cpus. Can you clarify your numbers above or am I mis-reading???
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