Re: 12 disks raid setup

[Franck Routier <franck(dot)routier(at)axege(dot)com>]

Hi,

my Raid controller is an Adaptec 31205 SAS/RAID controller. The battery
was an option, but I didn't know it at purchase time. So I have no
battery, but the whole system is on an UPS.

I have done quite a few tests using bonnie++, focusing on 'random seek'
results, and found out that:

1) linux md raid 10 performs better than Adaptec hardware raid in this
field (random seek) by 15%, quite consistently
2) hardware raid is better on sequential output
3) md outperforms it again when coming to sequential read, especially
with far layout option.

So in fact I think I will use md raid, but still don't know with which
layout (3x4 or 1x12).
What would you suggest as a benchmarking method ? Simply issue a few big
queries that I expect to be usual and see how long it last, or is there
a more convinient and or "scientific" method ?

Thanks,
Franck