Re: advice on raid controller

>>>>> "RJ" == Richard Jones <rj@last.fm> writes:

RJ> Hi, i'm on the verge of buying a "MegaRAID SCSI 320-2" raid controller.
RJ> I need it to build a db server using 4x ultra320 scsi disks
RJ> i'm thinking raid 1+0 but will try with raid5 too and compare

No specific tips on that particular RAID, but in general it seems that
you want to *disable* the read-ahead and enable the write-back cache.
This is from reading on the linux megaraid developers list.

Also, for 4 disks, go with RAID 1+0 for your best performance.  I
found it faster.  However, with my 14 disk system, RAID5 is fastest.

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