Re: Benchmarking a large server

On Mon, May 9, 2011 at 3:59 PM, David Boreham <david_list@boreham.org> wrote:
>
>> hm, if it was me, I'd write a small C program that just jumped
>> directly on the device around and did random writes assuming it wasn't
>> formatted.  For sequential read, just flush caches and dd the device
>> to /dev/null.  Probably someone will suggest better tools though.
>
> I have a program I wrote years ago for a purpose like this. One of the
> things it can
> do is write to the filesystem at the same time as dirtying pages in a large
> shared
> or non-shared memory region. The idea was to emulate the behavior of a
> database
> reasonably accurately. Something like bonnie++ would probably be a good
> starting
> point these days though.

The problem with bonnie++ is that the results aren't valid, especially
the read tests.  I think it refuses to even run unless you set special
switches.

merlin