On Aug 14, 2006, at 3:56 PM, Bucky Jordan wrote:
> Seems to me the PERC5 has issues with layered raid (10, 50) as
> others have suggested on this list is a common problem with lower
> end raid cards. For now, I'm going with the RAID 5 option, however
> if I have time, I would like to test having the hardware do raid 0
> and doing raid 1 in the os, or vice versa, as proposed in other posts.
Wow, those are pretty awesome numbers.... I'm actually inclined to
try these as my DB servers again! Lately I've been using Sun X4100
with Adaptec RAID cards, but they don't transfer nearly as fast as
that on simple tests.
Of more interest would be a test which involved large files with lots
of seeks all around (something like bonnie++ should do that).
I too have noticed that Dell controllers don't like doing layered
RAID levels very well. All of mine are doing plain old RAID5 or
RAID1 only, and at that they are acceptable. The PERC 4/Si in the
1850 has been pretty fast at RAID1.
Thanks for sharing your numbers.