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pgsql: Buy back some of the cycles spent in more-expensive hash - Mailing list pgsql-committers

From [email protected] (Tom Lane)
Subject pgsql: Buy back some of the cycles spent in more-expensive hash
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Log Message:
-----------
Buy back some of the cycles spent in more-expensive hash functions by
selecting power-of-2, rather than prime, numbers of buckets in hash joins.
If the hash functions are doing their jobs properly by making all hash bits
equally random, this is good enough, and it saves expensive integer division
and modulus operations.

Modified Files:
--------------
    pgsql/src/backend/executor:
        nodeHash.c (r1.111 -> r1.112)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/executor/nodeHash.c.diff?r1=1.111&r2=1.112)
    pgsql/src/include/executor:
        hashjoin.h (r1.44 -> r1.45)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/executor/hashjoin.h.diff?r1=1.44&r2=1.45)

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