[CentOS] Need advice on storage

Tue Nov 13 16:03:56 UTC 2007
Ken Price <kprice at nowyouknow.net>

> Thanks Ken.That's a good thing  to know that software striping won't  
> really boost performance, i  then won't waste money on that avenue.   
> I cannot explain why as i  don't know about Linux drivers  
> architecture and general system low  level behavior but maybe  
> somebody on this list could give us a

It's not specific to Linux, but RAID in general.  You need more than  
two disks to get any significant increase in performance.  In fact,  
you may get better performance with Linux software RAID than hardware  
RAID.  Linux software RAID is really quite robust.

> clue.As i said on my previous post, i found that the server is   
> inside a rack that has a VTRAK 15100 SCSI to SATA Enclosure with a   
> free SCSI bus (the unit has 2 independant bus) and hard disk slots.   
>  I think we have a spare Adaptec 39160 so if it's the case, i could   
> go with this solution and buy 4 x WD 250 Gigs "YS" (RAID) serie   
> drives @ about 75$ each and put all this in RAID 10.  The unit   
> supports NCQ.  It remains to be seen how well it can perform even if  
>  they are talking about "up to 200 MBps".Regards,Guy Boisvert

I've used both the Promise UltraTrak SX8000 (8-disk RAID50) and  
UltraTrak SX4000
(4-disk Raid10).  Performance was adequate, but I was using Dell  
PERC2/3 RAID cards.  In testing, a plain-jane Adaptec SCSI card  
coupled with software RAID gave "significantly" better results.

Cheers.
-Ken