Re: RAID5 internal log question

[Austin Gonyou <austin@coremetrics.com>]

I disagree a little bit. If you have poor hardware, or "low-cost"
hardware pushing your RAID subsystem, then I'd say you will have bad IO
in these instances. 

In general, if you buy decent hardware, there shouldn't be a problem
with this, some caching RAID controllers though, still use simms, and
from experience, perform way slower than the newer ones with
DIMMs(PC100, etc). 

On Fri, 2002-02-15 at 15:34, Seth Mos wrote:
> At 23:04 15-2-2002 +0200, Mihai RUSU wrote:
> >Hi
> >
> > From the XFS FAQ and other threads on this list I understand that is
> >recommended to have the log of an XFS partition out of a RAID5. Is that
> >performance impact that bad also with hardware RAID ?
> >Because its rather strange to make that external log reside out of the
> >RAID with hardware RAID (I have to reboot and use the BIOS
> configuration
> >tool to setup another logical device which should not be RAID5 just
> only
> >for the XFS log).
> 
> Just with software raid. Most hardware raid controllers have cache
> onboard 
> which will make it far less noticeable.
> 
> 
> --
> Seth
> Every program has two purposes one for which
> it was written and another for which it wasn't
> I use the last kind.
-- 
Austin Gonyou
Systems Architect, CCNA
Coremetrics, Inc.
Phone: 512-698-7250
email: austin@coremetrics.com

"It is the part of a good shepherd to shear his flock, not to skin it."
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