Re: H/W RAID 5 on slower disks versus no raid on faster

On Thu, 21 Nov 2002, Rajesh Kumar Mallah. wrote:

> 
> Hi folks,
> 
> I have two options:
> 3*18 GB 10,000 RPM Ultra160 Dual Channel SCSI  controller + H/W Raid 5
> and 
> 2*36 GB 15,000 RPM Ultra320 Dual Channel SCSI and no RAID
> 
> Does anyone opinions *performance wise*  the pros and cons of above 
> two options.
> 
> please take in consideration in latter case its higher RPM and better
> SCSI interface. 

Does the OS you're running on support software RAID?  If so the dual 36 
gigs in a RAID0 software would be fastest, and in a RAID1 would still be 
pretty fast plus they would be redundant.

Depending on your queries, there may not be a lot of difference between 
running the 3*18 hw RAID or the 2*36 setup, especially if most of your 
data can fit into memory on the server.

Generally, the 2*36 should be faster for writing, and the 3*18 should be 
about even for reads, maybe a little faster.