On 14 Jun 2012, at 15:22, "Fernando Frediani (Qube)" 
<[email protected]> wrote:

> Well, as far as I know the amount of IOPS you can get from a RAID 5/6 is the 
> same that you get from a single disk. The write can not be acknowledged until 
> it is written to all the data and parity disks.

It can exceed that with battery back-up on the controller. With battery 
back-up, writes are often faster than reads (in all of IOPS, latency and 
throughput), at least until you hit the cache size limit. Sustained writes will 
not get such good performance because of the limit you mention, but random 
writes can still do pretty well, YMMV.

If you want to scale writes properly, you need some variant of RAID-10. I've 
got one server with RAID-10 across 6 SSDs, works well.

Marcus
-- 
Marcus Bointon
Synchromedia Limited: Creators of http://www.smartmessages.net/
UK info@hand CRM solutions
[email protected] | http://www.synchromedia.co.uk/



_______________________________________________
Gluster-users mailing list
[email protected]
http://gluster.org/cgi-bin/mailman/listinfo/gluster-users

Reply via email to