MSA Storage
1748053 Members
5104 Online
108758 Solutions
New Discussion

Raid 0+1 VS Raid5

 
BD User
New Member

Raid 0+1 VS Raid5

I have a new MSA1500CS, filled with 6 300GB drives.

With a Raid 5 I get about 1400GB
With a Raid 0+1 I get about 830GB

What are the performance differences with going with raid 0+1. Is there any HP docs that can help with these details.
Thanks in advance

 

 

P.S. This thread has been moved from General to Storage Area Networks (SAN) (Small and Medium Business). - Hp Forum moderator

2 REPLIES 2
Bill Costigan
Honored Contributor

Re: Raid 0+1 VS Raid5

There are all kinds of docs that explain the difference between the two RAID types.

Basically, with RAID 0+1 ech block is written to two different disks. Therefore you get about half the space available.

With RAID 5 a block is only written to a single disk and then a parity block is written for every set of 5 blocks. Therefore you get more usuable space.
e.g. 5/6 of the raw space is available.

Raid 0+1 is usually faster. each write requires 2 writes. With Raid 5 the parity needs to be recreated so each write requires 2 reads + 2 writes.

For reads the performance is much closer. Generally 1 read only requires a single disk access.

Patrick Terlisten
Honored Contributor

Re: Raid 0+1 VS Raid5

Hello,

it depends on you use case. If you're using heavy load databases you should use RAID 1+0. If you're serving files, then you should use RAID 5. RAID 5 needs 2 read and 2 write IOs for one (logical) write IO.

Take a look at this:
http://en.wikipedia.org/wiki/RAID

Hope this helps.

Best regards,
Patrick
Best regards,
Patrick