Allow repalloc() to give back space when a large chunk is downsized. Up to now, if you resized a large (>8K) palloc chunk down to a smaller size, aset.c made no attempt to return any space to the malloc pool. That's unpleasant if a really large allocation is resized to a significantly smaller size. I think no such cases existed when this code was designed, and I'm not sure whether they're common even yet, but an upcoming fix to encoding conversion will certainly create such cases. Therefore, fix AllocSetRealloc so that it gives realloc() a chance to do something with the block. This doesn't noticeably increase complexity, we mostly just have to change the order in which the cases are considered.
Back-patch to all supported branches. Discussion: https://postgr.es/m/20190816181418.GA898@alvherre.pgsql Discussion: https://postgr.es/m/3614.1569359...@sss.pgh.pa.us Branch ------ REL_11_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/82d0a46ea32d1f666192d197fa993fd9f07adbec Modified Files -------------- src/backend/utils/mmgr/aset.c | 142 +++++++++++++++++++++++------------------- 1 file changed, 77 insertions(+), 65 deletions(-)
