On Fri, 2004-10-15 at 11:44, KELEMEN Peter wrote: > [ Please do not address answers directly to me; I read the list. ] then filter out email based on duplicate message-ids! :-P > > [...] and we get the same crappy performance from that one too. > > Define `crappy': I get 770 MiB/s read with 3x 3ware 9500S-8MI. > (RAID00 hw-sw) When issueing random reads of 1 megabyte each, I get 2 gigabits/sec from the Highpoint, and 1.5 gigabits/sec from the 3ware, when using a single controller and 8 disks (WD 250GB). No RAID, just JBOD mode, all disks in use at once. > > Worse yet, the 9xxx series wants to hijack your disks unless you > > go out of your way to enable 'export JBOD' mode. You can't take > > a disk from a 9xxx controller and put it in a box with an 8506 > > -- the controller won't recognize it! > > Have you tried zapping the first and the last megabyte of the > disk? the 8506 won't even let me set the disk up as a JBOD. In order to zap it, I need yet another controller! (The Highpoint controller is "nice" in that it will recognize the 3ware superblock and not absorb it either!) > As I said, attractive pricing. Cannot get stellar hardware RAID > performance with crappy chipsets. :-) There's a turnover point > where you are killed by PCI bandwith limit when using a lot of > disks. That's the funny thing about the 3ware 12 disk controllers; they don't even have the bandwidth to support all 12 disks! It truly depends on what you want to use it for. If you want RAID5, you most likely want a hardware solution, so yeah, 3ware would be the way to go. If you want JBOD though, I'd go with Highpoint. Anyone know how the Adaptec holds up? I've heard they have better random IO support than the 3ware, and I think they're a hardware only solution too. Scott - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
