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Subject: Re: hashing in QS

Author: Gerd Isenberg

Date: 12:53:00 10/20/04

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On October 20, 2004 at 03:39:31, Gian-Carlo Pascutto wrote:

>On October 20, 2004 at 02:27:19, martin fierz wrote:
>
>>so i want to store the move itself in the hashtable instead of the moveindex
>>now, as probably everybody is doing.
>
>Naah.
>
>>the question i have is this: should i stick
>>with two separate tables for QS and main search? or should i just use a single
>>big table (seems more sensible to me). or should i do no hashing at all in QS?
>>any opinions on this?
>
>One table vs two tables seems like a clear case for one table to me (what would
>two tables gain, except less efficiency?).

hmm... probably reducing latency and/or tlb-misses.
I guess that is specially an issue with a shared table in a multi-threaded
environment. Remember Vincent's huge "latencies" with huge tables >= 512MByte.
If you use that only in main search > 0, it doesn't matter so much.

For qsearch a small (a few 100K) thread-local allways replace table may have
some advantages - at least in my dumb program ;-)

Gerd


>
>To hash or not to hash, that must be *tested*.
>
>--
>GCP



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