Re: Hash index use presently(?) discouraged since 2005: revive or bury it? - Mailing list pgsql-performance

Merlin Moncure <mmoncure@gmail.com> writes:
> just selects.  update test is also very interesting -- the only test I
> did  for for updates is 'update foo set x=x+1' which was a win for
> btree (20-30% faster typically).  perhaps this isn't algorithm induced
> though -- lack of wal logging could actually hurt time to commit
> because it deserializes i/o.

In 9.1+, you could remove WAL from the comparison by doing the tests on
an unlogged table.

            regards, tom lane