when last we saw our hero (Wednesday, May 08, 2002), Mike Hicks was madly tapping out: > On Wed, 2002-05-08 at 21:28, steve ulrich wrote: > > i've used the (A|D)1k's a few times and i've been quite impressed with > > their throughput. upwards of 40MB/s throughput, iirc. i think you've got > > something horribly misconfigured there. > > Yeah, there's definitely something wacky going on. I'm still looking > into it, but looks like we really need to update the firmware on these > things, and update the RAID Manager software. > > I'm actually looking at three systems we have. The first one I was > working on has 10 active 18GB disks, split into 5 RAID-5 LUNs (I believe > they're all spread across all disks). I initially measured it to have > transfer rates of around 4MB/s, but the commands I put in the previous > message more than doubled transfer rates to around 10MB/s. > > Another system is similarly configured, I believe it has 11 active 18GB > disks, with 7 RAID-5 LUNs. This system was at least partially tweaked > by an Oracle consultant, and shows much better performance. Block reads > and writes approach 20MB/s. Much better than the other systems I'm > looking at, though I have to think it could still be improved. I > haven't tweaked it at all yet, though, and have no plans to until I get > the other systems working better. i've seen this type of performance and better depending on the read-ahead capabilities of the controller for different types of applications with RAID 5. that doesn't sound too horribly out of whack with my interactions. sun has some decent tuning information in the RAID manager user guide. it's recommended reading if you're using this. http://docs.sun.com/ab2/@LegacyTocView?toc=SUNWab_179_1%3A%2Fsafedir%2Fspace3%2Fcoll1%2FSUNWosaab%2Ftoc%2FRSMARRAYUG%3ARSMARRAYUG%3Aclose;bt=RAID+Manager+6.1+User%27s+Guide&Ab2Lang=C&Ab2Enc=iso-8859-1 > > The third system has 10 active 9GB disks, with only 2 RAID-5 LUNs. Like > the first system, it has shown transfer rates around 4MB/s. I tried > using the commands I ran on the first system, but it appears they had no > effect. > > 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. -- steve ulrich sulrich at botwerks.org PGP: 8D0B 0EE9 E700 A6CF ABA7 AE5F 4FD4 07C9 133B FAFC -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 230 bytes Desc: not available Url : http://shadowknight.real-time.com/pipermail/tclug-list/attachments/20020509/b457514c/attachment.pgp