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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2009-07-21 19:53:12 +0000 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2009-07-21 19:53:12 +0000 |
| commit | ab5b4e2f9ede250bd77d09aa8ec60bfeb982fb01 (patch) | |
| tree | 4ca18782a0d367a3b9ae96ed3d1927843bafd60c /src/backend/commands/async.c | |
| parent | f3f45c87d23b800913fb8ea88fe2d713f6b9dd74 (diff) | |
| download | postgresql-ab5b4e2f9ede250bd77d09aa8ec60bfeb982fb01.tar.gz postgresql-ab5b4e2f9ede250bd77d09aa8ec60bfeb982fb01.zip | |
Speed up AllocSetFreeIndex, which is a significant cost in palloc and pfree,
by using a lookup table instead of a naive shift-and-count loop. Based on
code originally posted by Sean Eron Anderson at
http://graphics.stanford.edu/%7eseander/bithacks.html.
Greg Stark did the research and benchmarking to show that this is what
we should use. Jeremy Kerr first noticed that this is a hotspot that
could be optimized, though we ended up not using his suggestion of
platform-specific bit-searching code.
Diffstat (limited to 'src/backend/commands/async.c')
0 files changed, 0 insertions, 0 deletions