Logical Tape Set: lazily allocate read buffer.
The write buffer was already lazily-allocated, so this is more
symmetric. It also means that a freshly-rewound tape (whether for
reading or writing) is not consuming memory for the buffer.
Discussion: https://postgr.es/m/97c46a59c27f3c38e486ca170fcbc618d97ab049.camel%40j-davis.com
Branch
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master
Details
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https://git.postgresql.org/pg/commitdiff/7fdd919ae7550f478e7ae4031f7f439278cf2282
Modified Files
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src/backend/utils/sort/logtape.c | 43 +++++++++++++++++++++++++++++++++-------
1 file changed, 36 insertions(+), 7 deletions(-)