Reduce memory consumption for pending invalidation messages.
The existing data structures in inval.c are fairly inefficient for
the common case of a command or subtransaction that registers a small
number of cache invalidation events. While this doesn't matter if we
commit right away, it can build up to a lot of bloat in a transaction
that contains many DDL operations. By making a few more assumptions
about the expected use-case, we can switch to a representation using
densely-packed arrays. Although this eliminates some data-copying,
it doesn't seem to make much difference time-wise. But the space
consumption decreases substantially.
Patch by me; thanks to Nathan Bossart for review.
Discussion: https://postgr.es/m/2380555.1622395376@sss.pgh.pa.us
Branch
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master
Details
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https://git.postgresql.org/pg/commitdiff/3aafc030a53621e91be2e7c1c72b5f3e8b103486
Modified Files
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src/backend/utils/cache/inval.c | 514 ++++++++++++++++++++++------------------
1 file changed, 286 insertions(+), 228 deletions(-)
