[ILUG] I/O benchmarking tools

[stephen mulcahy]

On 15/02/11 14:12, Conor Wynne wrote:
> What tools do you guys recommend for doing some I/O benchmarking.
>
> I've been using iozone with 20 threads, but the figures I'm getting back
> are just mental. Like more than the array should be capable of....
>
> The is the comand line I've been testing with:
>
> /opt/iozone/bin/iozone -R -l 20 -u 20 -r 4k -s
> 100m -F file1 file2 file3 file4 file5 file6 file7 file8 file9 file10
> file11 file12 file13 file14 file15 file16 file17 file18 file19 file20
> |tee -a /root/Test_20-threads_Iozone.txt

iozone has a pretty good reputation.

I like bonnie++ because it has a simpler interface but afaik iozone is 
more accurate and more powerful.

if you're doing any filesystem testing, the first thing you need to be 
careful of is testing the performance of your os caches rather than the 
actual filesystem. So to be sure to be sure, you should use a test-file 
size that is a multiple of your system's memory size (this is certainly 
the case with bonnie++ and I assume the same with iozone).

Try that and see if it gives any improvement.

-stephen

-- 
Stephen Mulcahy     Atlantic Linux         http://www.atlanticlinux.ie
Registered in Ireland, no. 376591 (144 Ros Caoin, Roscam, Galway)