[Sunhelp] SSA 112

[Gregory Leblanc]

> -----Original Message-----
> From: Bjrn Ramqvist [mailto:brt at osk.sema.se]
> Sent: Wednesday, July 12, 2000 12:04 AM
> To: sunhelp at sunhelp.org
> Subject: Re: [Sunhelp] SSA 112
> 
[snip]
> Second thing is the "just JBOD" feature. This means you have 
> to put all
> the stress on the host running the array, which means you 
> need a pretty
> fast host to run this baby. On SS1000E's with 85MHz 
> SuperSPARC-II's it's
> almost painful running RAID-5. Pure RAID-0 (striping w/o parity) would
> probably be faster.
> So, an Ultra-1 or similar would do the job more efficient.

I'd stay away from Software RAID 5 in general.  I'm not familiar with the
RAID functionality in DiskSuite, but a couple of other solutions allow for
RAID 01, which is creating mirrors, and striping across them.  You have a
capacity of 1/2 that of the total size of all of your disks, but it should
be low on processor useage, and VERY fast for reads, not that fast for
writes.  

> Drivers for the array and hostcontroller is included with both Solaris
> and Linux, although you need Disksuite or similiar on Solaris to use
> striping. "ssaadm" and "luxadm" is the tools to configure the array.
> Linux support is pretty stable, and with the built-in striping-support
> it makes this a little bit easier.
> (I have no idea about performance using this combination)

I can't say specifically, but software RAID support on Linux has been very
good for me.  Mirroring saved me from a server rebuild last week.  :)
	Grego