Re: Postgresql performance degrading... how to diagnose the root cause

Hi,
> I don't know that tcp-b does
tpcb.jar is a java implementation of the http://www.tpc.org/tpcb/
benchmark. It is not particularly representative of my workload, but
gives a synthetic, db-agnostic, view of the system performance.
We use it to have quick view to compare differents servers (different
OS, different RDBMS, etc...).

That said, the test wil create tables, load them with data, and perform
some transactions on them.
The point that makes me wonder what happens, is that the test run on my
main database is slow, while the same test run on a database on its own
is quick.
This is the same postgresql cluster (same postgresql.conf), same
tablespace (so same disks), same hardware obviously.

Regarding the server activity, it seems quite flat : iostat shows that
disks are not working much (less than 5%), top shows only one active
core, and load average is well under 1...


>
> http://wiki.postgresql.org/wiki/Show_database_bloat
How do I interpret the output of this query ? Is 1.1 bloat level on a
table alarming, or quite ok ?

Franck