On Wed, Dec 16, 2015 at 4:24 PM, Peter Geoghegan <p...@heroku.com> wrote:
> On Wed, Dec 16, 2015 at 12:28 PM, Robert Haas <robertmh...@gmail.com> > wrote: > >> I seem to be able to produce these sorting patches at a much greater > >> rate than they can be committed, in part because Robert is the only > >> one that ever reviews them, and he is only one person. > > > > I object to that vicious slander. I am at least three people, if not > more! > > I was referring only to the Robert that reviews my sorting patches. :-) > > > Meanwhile, I did some simple benchmarking on your latest patch on my > > MacBook Pro. I did pgbench -i -s 100 and then tried: > > > > create index x on pgbench_accounts (aid); > > create index concurrently x on pgbench_accounts (aid); > > > > The first took about 6.9 seconds. The second took about 11.3 seconds > > patched versus 14.6 seconds unpatched. That's certainly a healthy > > improvement. > > That seems pretty good. It probably doesn't matter, but FWIW it's > likely that your numbers are not as good as mine because this ends up > with a perfect logical/physical correlation, which the quicksort > precheck [1] does very well on when sorting the TIDs (since input is > *perfectly* correlated, as opposed to 99.99% correlated, a case that > does poorly [2]). > > > I have also reviewed the code, and it looks OK to me, so committed. > > Thanks! > > [1] Commit a3f0b3d68f9a5357a3f72b40a45bcc714a9e0649 > [2] http://www.postgresql.org/message-id/54eb580c.2000...@2ndquadrant.com > -- > Peter Geoghegan > > > -- > Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-hackers > My apologies to Peter and all the Roberts, I wasn't able to set up a test fast enough. Glad it got committed.
