Bryan J. Smith schrieb:
> Ralf Gross <Ralf-Lists@xxxxxxxxxxxx> wrote:
> ...
> I'm completely biased though, I assemble file and database servers,
> not web or other CPU-bound systems. Turning my system interconnect
> (not the CPU, a PC CPU crunches XOR very fast) into a bottlenecked
> PIO operation is not ideal for NFS writes or large record SQL commits
> in my experience. Heck, one look at NetApp's volume w/NVRAM and
> SPE-accelerated RAID-4 designs will quickly change your opinion as
> well (and make you wonder if they aren't worth the cost at times as
> well ;).
Thanks for all the details. Before I leave the office (it's getting
dark here): I think the Overland RAID we have (48x Disk) is from the
same manufacturer (Xyratex) that builds some devices for NetApp.
Our profile is not that performance driven, thus the ~200MB/s
read/write performace is ok. We just need cheap storage ;)
Still I'm wondering how other people saturate a 4 Gb FC controller
with one single RAID 5. At least that's what I've seen in some
benchmarks and here on the list.
If dd doesn't give me more than 200MB/s, the problem could only be the
array, the controller or the FC connection. Given that other setup are
similar and not using different controllers and stripes.
Ralf
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