Author: Robert Hyatt
Date: 20:25:04 10/28/03
Go up one level in this thread
On October 28, 2003 at 16:04:46, Matthew Hull wrote: >On October 28, 2003 at 09:48:52, Robert Hyatt wrote: > >>On October 27, 2003 at 21:23:13, Vincent Diepeveen wrote: >> >>>On October 27, 2003 at 20:09:55, Eugene Nalimov wrote: >>> >>>>On October 27, 2003 at 20:00:54, Robert Hyatt wrote: >>>> >>>>>On October 27, 2003 at 19:57:12, Eugene Nalimov wrote: >>>>> >>>>>>On October 27, 2003 at 19:24:10, Peter Skinner wrote: >>>>>> >>>>>>>On October 27, 2003 at 19:06:51, Eugene Nalimov wrote: >>>>>>> >>>>>>>> >>>>>>>>I don't think you should be afraid. 500 CPUs is not enough -- you need >>>>>>>>reasonable good program to run on them. >>>>>>>> >>>>>>>>Thanks, >>>>>>>>Eugene >>>>>>> >>>>>>>I would bet on Crafty with 500 processors. That is for sure. I know it is quite >>>>>>>a capable program :) >>>>>>> >>>>>>>Peter. >>>>>> >>>>>>Efficiently utilizing 500 CPUs is *very* non-trivial task. I believe Bob can do >>>>>>it, but it will be nor quick nor easy. >>>>>> >>>>>>Thanks, >>>>>>Eugene >>>>> >>>>> >>>>>If the NUMA stuff doesn't swamp me. And if your continual updates to the >>>>>endgame tables doesn't swamp me. We _might_ see some progress here. :) >>>>> >>>>>If I can just figure out how to malloc() the hash tables reasonably on your >>>>>NUMA platform, without wrecking everything, that will be a step... >>>> >>>>Ok, just call the memory allocation function exactly where you are calling it >>>>now, and then let the user issue "mt" command before "hash" and "hashp" if (s)he >>>>want good scaling. >>>> >>>>Thanks, >>>>Eugene >>> >>>That's why i'm multiprocessing. All problems solved at once :) >> >> >>And several added. Duplicate code. Duplicate LRU egtb buffers. Threads >>are not necessarily bad here. We're hitting 6.75M+ nodes per second on a quad >>opteron at 1.8ghz. That's not bad. I'll post some output when everything is >>cleaned up and finalized, particularly allocating the hash tables. > > >Is that with the SMP version or with NUMA version? > >MH It is a hybrid. The new SMP version will support NUMA. Eugene has already written windows NUMA support and it will automatically work if you use a NUMA platform with windows. I'll do this on Linux once I have a NUMA box with a Linux kernel to play with. Version 19.5 will have these changes. You won't see any external differences. I just now allocate things like the tree block on a local processor for efficiency. We are working on distributing the Hash table across all processors. Eugene has written something there although I am not sure we are done with it yet... More as it develops. As I had mentioned, I had already done most of this once, already, for the NUMA alpha project I worked on last year. It wasn't very hard to do it a second time, it took a couple of hours. Note that it was not a complete re-write, as I had mentioned previously, in spite of what some thought was required. It isn't _that_ big a deal.
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