aboutsummaryrefslogtreecommitdiff
path: root/src/backend/access/gist/gistxlog.c
diff options
context:
space:
mode:
authorTom Lane <tgl@sss.pgh.pa.us>2006-03-21 19:49:15 +0000
committerTom Lane <tgl@sss.pgh.pa.us>2006-03-21 19:49:15 +0000
commita3f0b3d68f9a5357a3f72b40a45bcc714a9e0649 (patch)
treef9a5603f10b89badd1f7de5af3bfc16865224ea2 /src/backend/access/gist/gistxlog.c
parent570b726533fb561bc5a35ba50ea944f139a250d5 (diff)
downloadpostgresql-a3f0b3d68f9a5357a3f72b40a45bcc714a9e0649.tar.gz
postgresql-a3f0b3d68f9a5357a3f72b40a45bcc714a9e0649.zip
Improve performance of our private version of qsort. Per recent testing,
the logic it contained to switch to insertion sort for near-sorted input was in fact a big loss, because it could fairly easily be fooled into applying insertion sort to large subfiles that weren't all that well ordered. Remove that, and instead add a simple check for already-perfectly-sorted input, as per suggestion from Dann Corbit. This adds at worst O(N*lgN) overhead, and usually far less, while sometimes allowing a subfile sort to finish in O(N) time. Preliminary testing says this is an improvement over the basic Bentley & McIlroy code for many nonrandom inputs, and it costs almost nothing when the input is random.
Diffstat (limited to 'src/backend/access/gist/gistxlog.c')
0 files changed, 0 insertions, 0 deletions