At 01:35 PM 12/12/2006, Daniel van Ham Colchete wrote:
I just made another test with a second Gentoo machine:
<snip>
The results showed no significant change. The conclusion of today's
test would be that there are no improvement at PostgreSQL when using
-march=prescott.
I only see 3 diferences between yesterday's server and today's: the
kernel version (y: 2.6.18, t:2.6.17), the server uses an IDE
harddrive (yesterday was SATA), and the gcc version (3.4.6 -> 4.1.1).
I don't know why yesterday we had improved and today we had not.
SATA HD's, particularly SATA II HD's and _especially_ 10Krpm 150GB
SATA II Raptors are going to have far better performance than older IDE HDs.
Do some raw bonnie++ benches on the two systems. If the numbers from
bonnie++ are close to those obtained during the pgbench runs, then
the HDs are limiting pgbench.
Best would be to use the exact same HD IO subsystem on both boxes,
but that may not be feasible.
In general, it would be helpful if the entire config, HW + OS + pg
stuff, was documented when submitting benchmark results.
(For instance, it would not be outside the realm of plausibility for
Guidos C2D laptop to be HD IO limited and for Micheal's 2.5 GHZ P4 PC
to be CPU limited during pgbench runs.)
Ron Peacetree
