Thread: pgsql: Incorporate a couple of recent tuplesort.c improvements into

Log Message:
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Incorporate a couple of recent tuplesort.c improvements into tuplestore.c.
In particular, ensure that enlargement of the memtuples[] array doesn't
fall foul of MaxAllocSize when work_mem is very large, and don't bother
enlarging it if that would force an immediate switch into 'tape' mode anyway.

Modified Files:
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    pgsql/src/backend/utils/sort:
        tuplestore.c (r1.25 -> r1.26)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/sort/tuplestore.c.diff?r1=1.25&r2=1.26)