Re: Benchmarking a large server

On Mon, May 9, 2011 at 3:32 PM, Chris Hoover <revoohc(at)gmail(dot)com> wrote:
> I've got a fun problem.
> My employer just purchased some new db servers that are very large.  The
> specs on them are:
> 4 Intel X7550 CPU's (32 physical cores, HT turned off)
> 1 TB Ram
> 1.3 TB Fusion IO (2 1.3 TB Fusion IO Duo cards in a raid 10)
> 3TB Sas Array (48 15K 146GB spindles)

my GOODNESS! :-D. I mean, just, wow.

> The issue we are running into is how do we benchmark this server,
> specifically, how do we get valid benchmarks for the Fusion IO card?
>  Normally to eliminate the cache effect, you run iozone and other benchmark
> suites at 2x the ram.  However, we can't do that due to 2TB > 1.3TB.
> So, does anyone have any suggestions/experiences in benchmarking storage
> when the storage is smaller then 2x memory?

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.

merlin