> -----Original Message-----
> From: Carlos Carvalho [mailto:[EMAIL PROTECTED]]
> Sent: Monday, August 07, 2000 10:57 AM
> To: Andrea Arcangeli
> Cc: [EMAIL PROTECTED]
> Subject: Re: raid-2.2.17-A0 cleanup for LVM
>
> >In 2.2.x that's not possible but for _very_ silly reasons.
>
> So can't this be fixed?
I wouldn't expect it to be fixed. 2.4 is well on it's way, and seems to
have quite a few "silly" things fixed.
> >On 2.4.x we now have a modular and recursive make_request
> callback, that
> >will allow us to handle all the volume management layering
> correctly (so
> >if raid5 on top of raid0 isn't working right now in 2.4.x send a bug
> >report ;).
>
> Yes, but it's useless because of the abysmal (absence of) speed. And
> all the VM problems... The machine I need raid50 on is a central
> server, if it stops everything else goes down. In fact I'm not using
> 2.4 on it precisely because of the VM/raid problems!! :-( :-(
>
> If I can't do raid50 on our server I'll have to resort to raid10,
> losing 50% of our so expensive disks...
No, DASD (disks) are cheap, compared with other things, like upgrading the
processor(s) on your oracle or DB2 server. If you're dealing with SCSI
(which you must be, for that many drives), and using RAID 5, speed can't be
that paramount. Just put another drive on each bus. I know, nobody likes
to spend money on disks, but they're cheaper than losing data.
Greg
