[CentOS] Need advice on storage

Tue Nov 13 16:57:17 UTC 2007
Ross S. W. Walker <rwalker at medallion.com>

Ken Price wrote:
> > 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.

The PERC2/3 cards were junk. These days the PERC 5e and newer
provide performance levels as good or better then Linux software
RAID, plus onboard write-back cache which software RAID doesn't


This e-mail, and any attachments thereto, is intended only for use by
the addressee(s) named herein and may contain legally privileged
and/or confidential information. If you are not the intended recipient
of this e-mail, you are hereby notified that any dissemination,
distribution or copying of this e-mail, and any attachments thereto,
is strictly prohibited. If you have received this e-mail in error,
please immediately notify the sender and permanently delete the
original and any copy or printout thereof.