Can RAID 5 Use a 4-Disk Array? 1

[JohnBates]

hi experts,

I've configued RAID 5 using 4 disk drives on an IBM e-server.

My IT manager thinks that with HP Proliant servers, the number of drives in HP's RAID 5 array must be an odd number - 3, 5 etc.

Does anyone know if that may be true ?

(Sorry, but I couldn't find a forum for HP.)

Thanks for any info.
John

 

[technome]

Not true...

An even number of drives is slighly preferable, if the raid adapter has multiple channels. Aside from this, more drives beyond the 3 minimum gives better throughput, up to a certain point. On my Lsi u320-2x, 5 drives gives about the maximum throughput. I use 5 drives on my home server, an odd number due to the cost of the drives.

Check this out for raid 5 throughput vs number of drives...

http://forums.2cpu.com/showthread.php?s=&threadid=60523

 

[technome]

This thread is better as it show scsi benchmarks, though no comarison to three drives arrays

http://forums.2cpu.com/showthread.php?s=&threadid=47784&highlight=benchmark

If you search for the user Femmet on this site, he has dicussed the throughput differences of adding drives beyond the minimum.

 

[JohnBates]

Thanks technome. Your post is very helpful.

So I guess I can tell my boss he's wrong this time