pgsql-server/src/backend/commands analyze.c

CVSROOT:    /cvsroot
Module name:    pgsql-server
Changes by:    tgl@postgresql.org    02/08/10 20:08:48

Modified files:
    src/backend/commands: analyze.c

Log message:
    Now that we allow ANALYZE to run inside a transaction block, the locks
    it takes could be held for quite awhile after the analyze step completes.
    Rethink locking of pg_statistic in light of this fact.  The original
    scheme took an exclusive lock on pg_statistic, which was okay when the
    lock could be expected to be released shortly, but that doesn't hold
    anymore.  Back off to a normal writer's lock (RowExclusiveLock).  This
    allows concurrent ANALYZE of nonoverlapping sets of tables, at the price
    that concurrent ANALYZEs of the same table may fail with 'tuple
    concurrently updated'.