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Cc: Jeff Tchang <jeff.tchang@gmail.com>, freebsd-performance@freebsd.org
Subject: Re: 3Ware 7500-4 Slow
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On Mon, 5 Sep 2005, Chuck Swiger wrote:

> Small writes are pretty much the worst-case scenario for RAID-5,

Such as mail servers?
How about for a DB server which is mostly read only?

> normal to see a very significant performance drop-- by up to an order of 
> magnitude-- from the performance of a bare drive.


At which point Raid 5 starts to perform better?
6,8,10 drives?


How about RAID 10 for a DB server?
I have been trying to convince the "powers that be" that SCSI would be 
much better.. but the price difference is just too astronomical for the 
capacities we need (500GB to 2 TB)

Even 10K RPM IDE drives seem like would be a problem since they are mostly 
small in size.