Re: SSD + RAID

On Thu, Nov 19, 2009 at 10:01 AM, Merlin Moncure <mmoncure(at)gmail(dot)com> wrote:
> On Wed, Nov 18, 2009 at 11:39 PM, Scott Carey <scott(at)richrelevance(dot)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

Seeing as how pgbench only goes to scaling factor of 4000, are the any
plans on enlarging that number?