Re: Why would writes to pgsql_tmp bottleneck at 1mb/s?

> Maybe I'm not an idiot (really!) even with almost 2GB of maintenance_mem, PG
> still writes to pgsql_tmp no faster than 2MB/s. I think there may be an
> artificial bottleneck there. Question is, PostgreSQL, OS or hardware?

I'm curious: what is your cpu usage while this is happening? I've
noticed similar slow index creation behaviour, but I did not make any
connection to pgsql_temp (because it was not on a separate partition).
I was indexing an oid field of a 700GB table and it took about four
days on a 1.2GHz UltraSparcIII (solaris 9, 8GB core). I noticed that
the one CPU that was pegged at near 100%, leading me to believe it
was CPU bound. Odd thing is that the same operation on a 2GHz Pentium
IV box (Linux) on the same data took about a day. Truss showed that
a great majority of that time was in userland.

-Aaron