Re: RAID config for mailboxes host

Emmanuel Halbwachs wrote (ao):
> Let this physical server:
> 
>     Dell R710
>     2x6 cores 2.3 GHz
>     48 GB RAM
>     12 disks 600 GB, 15 ktr/min
>     only one RAID card H700
> 
> for the usage of a rather small mailhost:
> 
>     MDA
>     IMAP/POP for 1500 mailboxes (Maildir)
>     webmail
>     (MX are other machines)
> 
> We consider two RAID config for the 12 disks:
> 
>         A   2 disks RAID 1 for system
>            10 disks RAID 6 for mailbox space
> 
>         B  12 disks RAID 6 for the whole 
> 
> In A, we lose 1.2 (raw) TB with respect to B. Advocates of A say that
> in B, the heads read/write activity of the mailboxes will seriously
> impact the system performance. In A, the system has its own axes,
> separate from the mailboxes ones.

I would go for scenario B. If your workload is too much for the system,
you are screwed in both scenario A and B anyway, and in B you have extra
spindles.

Btw, any reason you go with spinning disks and not with SSDs like Intel
710/720? SSDs are a good fit for maildir workload (random IO).

	Sander

-- 
Humilis IT Services and Solutions
http://www.humilis.net