Hmm. replying a few days late.. On Thu, 2002-05-09 at 07:56, steve ulrich wrote: > when last we saw our hero (Wednesday, May 08, 2002), > Mike Hicks was madly tapping out: > > I mentioned in my previous message that we also have a Linux/Sparc > > system that apparently has much better transfer rates. However, I > > should point out that it's using software RAID-0 across 3 9GB disks. > > Since it's speed approaches 30MB/s, I presume that each 9GB disk can > > transfer about 10MB/s. The 18GB drives in other systems probably have > > similar or better performance. > > bear in mind that w/RAID 0 you don't get any redundancy (you lack a > parity disk) that said you should see significant performance wins > here. comparing a RAID 5 config vs. a RAID 0 config is horribly > misleading and is comparing apples to oranges. Yeah, the RAID-0 is being used as an Amanda holding disk -- a space to temporarily store backed-up filesystems before they get dumped to tape. We needed to be able to use the disk space as efficiently as possible and have high-speed access. It's not being used as long-term storage (at most, backed-up filesystems might stay on there a week), so I figured the data-redundancy wasn't necessary. As for comparing RAID-0 to RAID-5, yeah, that's a stretch. However, I figured that I could at least get a good guess as to how fast each drive is. Ignoring bus contention issues, I figure each drive probably maxes out at around 1/3 the measured transfer rate. Since that adds up to about 10MB/s, I figured the RAID-5 array should be getting at least that speed. Anyway, we're still looking into it, but won't be able to do much until the semester is over. -- _ _ _ _ _ ___ _ _ _ ___ _ _ __ You see, it's like the old / \/ \(_)| ' // ._\ / - \(_)/ ./| ' /(__ saying, "Everybody loves a \_||_/|_||_|_\\___/ \_-_/|_|\__\|_|_\ __) cane." [ Mike Hicks | http://umn.edu/~hick0088/ | mailto:hick0088 at tc.umn.edu ] -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 232 bytes Desc: This is a digitally signed message part Url : http://shadowknight.real-time.com/pipermail/tclug-list/attachments/20020512/6606594e/attachment.pgp