Fix excessive memory consumption in the new sort pre-reading code.
LogicalTapeRewind() should not allocate large read buffer, if the tape
is completely empty. The calling code relies on that, for its
calculation of how much memory to allocate for the read buffers. That
lead to massive overallocation of memory, if maxTapes was high, but
only a few tapes were actually used.
Reported by Tomas Vondra
Discussion: <7303da46-daf7-9c68-3cc1-9f83235cf37e@2ndquadrant.com>
Branch
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master
Details
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http://git.postgresql.org/pg/commitdiff/b56fb691b0033f9b86e0552bd5adfd485f05eef6
Modified Files
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src/backend/utils/sort/logtape.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
