Jay West declared on Sunday 10 October 2004 01:29 pm:
> It was written....
> > I would agree with you if the server was a SPARCstation5 or
> > something. As you said yourself, we've got cycles to burn here.
>
> Just because you CAN do a thing, doesn't mean you should. I view cpu
> cycles as precious and not to be used frivolously even when available
> in good supply. Perhaps it dates back to my mentality of pouring over
> machine code to save a cycle here and there :)
>
> > The last time I logged into that box it had over 600 days uptime,
> > and we have several production machines of our own running RAID1 in
> > software.
>
> I wasn't saying it wasn't reliable, just not the best use of the main
> cpu. I'd also lay odds that it isn't as fast.
As well, I've played quite a bit with software RAID, and have used
Linux's software raid 5 at work on production Compaq quad Pentium Pro
boxes, on a Sun E3000, and various other things including some 533MHz
Alpha machines with Qlogic FC cards and FC JBODs. I've never noticed a
bit hit in CPU performance when using software raid. In every case, I
was able to max out the I/O channel performance when doing benchmarks of
the software raid.
I've never had data loss from software raid, except when I failed two
drives in a raid 5 set at once (oops). Even pulling the cord when the
machine was rebuilding the raid left the data intact, which impressed
me.
You might get better speed by using a hardware raid card, but unless
you're doing stuff that needs high performance. Besides, I've had more
issues with hardware raid doing stupid things or having poor
performance, but that's probably because I was using "older" PC raid
stuff.
Pat
--
Purdue University ITAP/RCS --- http://www.itap.purdue.edu/rcs/
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Received on Sun Oct 10 2004 - 23:49:08 BST