On Wed, Nov 18, 2009 at 11:39 PM, Scott Carey <scott@richrelevance.com> wrote:
> Well, that is sort of true for all benchmarks, but I do find that bonnie++
> is the worst of the bunch. I consider it relatively useless compared to
> fio. Its just not a great benchmark for server type load and I find it
> lacking in the ability to simulate real applications.
I agree. My biggest gripe with bonnie actually is that 99% of the
time is spent measuring in sequential tests which is not that
important in the database world. Dedicated wal volume uses ostensibly
sequential io, but it's fairly difficult to outrun a dedicated wal
volume even if it's on a vanilla sata drive.
pgbench is actually a pretty awesome i/o tester assuming you have big
enough scaling factor, because:
a) it's much closer to the environment you will actually run in
b) you get to see what i/o affecting options have on the load
c) you have broad array of options regarding what gets done (select
only, -f, etc)
d) once you build the test database, you can do multiple runs without
rebuilding it
merlin
merlin