Peter Childs <blue.dragon@blueyonder.co.uk> writes:
> 1. Shut it down the database.
> 2. Move data/pg_xlog and data/pg_clog to another drive.
> 3. Symlink data/pg_xlog and data/pg_clog to this other drive.
> 4. Restart the database.
Actually, my recommendation would be to leave pg_clog on the data drive;
it's more of a data file than a log. The reason for putting WAL
(pg_xlog) on a separate drive is that it'w written a lot, and written
perfectly sequentially, and so you can reduce seek overhead a bunch if
writing WAL is the only thing that particular disk head has to do.
Putting pg_clog onto the same drive introduces the seek overhead you
were trying to avoid.
regards, tom lane