Dell PE2950 - SAS 6/iR

[FreeBSD]

Maciej Suszko a écrit :
> I think about buying Dell PE2950 with SAS 6/iR integrated RAID
> controller. It would be double Intel Quad Core Xeon E5420 with 3.5" SAS
> 15k RPM disks connected to SAS 6/iR RAID controller.
>
> I'm curious if anyone is running FreeBSD-7.0-RELEASE on such machine
> and if there any problems with this controller - is SAS 6/iR supported
> by mpt or mfi? Anyone happily using it?
>   
I never tried SAS 6 but I have SAS 5 in a few Dell servers and it's 
performance is horrible. I tried some tips I read to optimize the 
performance but none worked (I must admit that I didn't tried that hard 
but still...). Just to compare, I have the exact same disk (the same 
3,5" SAS 15K that you plan to buy) in a PowerEdge 860 with SAS 5 and in 
a PowerEdge 1950 with PERC5 (both in RAID 1) and the performance are 
like day and night (tested with dbench):
SAS 5: Throughput 98.9811 MB/sec 4 procs
PERC5: Throughput 321.704 MB/sec 4 procs

The last server I bought is a PowerEdge 840 with PERC5 but this time 
with 7200RPM SATA drives (3 in RAID 5) and the performance is still 
impressive : Throughput 266.81 MB/sec 4 procs

I highly recommand upgrading to the PERC controller.

SAS5 is recognized by the mpt driver and PERC5 by mfi.

YMMV,

Martin