On Fri, Aug 22, 2008 at 09:30:17PM +0200, Daniel Hokka Zakrisson wrote: > Herbert Poetzl wrote: > > On Fri, Aug 22, 2008 at 06:57:55PM +0100, Ed W wrote: > >> Herbert Poetzl wrote: > >> >situation: one of my raid controllers suddenly failed > >> >and I need to replace it with a new one (currently > >> >the raid is offline, and I don't have access to the > >> >data). as I was not very happy with the controller > >> >(an Intel/LSI one, which only caused issues from the > >> >beginning), I want to replace it with a different > >> >model from Adaptec (specifically the RAID 31605), > >> >which seems to have good support and all the features > >> >I am looking for. > >> > >> Just an aside, but can I ask why a fancy raid controller? > > > > that's simple, with 12+ disks you have almost no > > chance to attach them to _any_ motherboard ... > > > > besides that, normal SATA controllers do not have > > the bandwith to get performant I/O over e.g. > > port multipliers, so the only choice is a big > > throughput raid controller ... note that I could > > live without the fancy hardware raid features, > > but you really don't get any 8-16 port SATA > > controller without hardware raid ... > > For this, I use Supermicro's AOC-SAT2-MV8. It's an 8-port card that > costs less than 100 USD, though it does require a PCI-X slot. Granted > it's got a Marvell chipset, but I haven't had any problems with it. hmm, definitely worth a thought. are there any dual PCI-X motherboards for Core2 Intels out there (preferably with good linux support :)? > > note that disk I/O is the main bottleneck of > > todays servers/machines, and compiling kernels > > means moving a lot of data from/to disk > > > >> I personally LOVE the top end stuff, for example have some very good > >> experiences with Compaq battery backed scsi controllers. But I have > >> had nothing but disappointment with even decent 3Ware controllers > >> and I notice no difference at all over builtin SATA controllers, > >> which coupled with a nice motherboard often mean you can have 8-10 > >> controllers right on the bridge and hence high speed access > >> > >> Battery backup is missing off the onboard controllers though and if > >> you have a DB application (probably not if you are getting 1.5GB > >> disks) then this is a big deal, but otherwise it's not likely to make > >> much difference (hey not teaching you to suck eggs - I'm sure you > >> already know if it will help your workload!) > > > > yes, as mentioned, it definitely helps my specific > > workload to maximize disk I/O and minimize latency > > > >> In summary though unless you need the battery backup I would recommend > >> a new motherboard with enough onboard ports to meet your needs - > >> forget what I have but I bought some bits of the office machine and it > >> supports my quad intel thing with I think 8+ sata ports? > > > >> > and I could > >> >also make good use of three or four of those new > >> >1.5TB SATA disks from Seagate (ST31500341AS) or the > >> >1TB models (ST31000340AS) to retire one of my older > >> >disk arrays (150-200 USD/ 120-150 EUR each) > >> > >> The 1.5TB have quite a price hike, even the 1TB are I think slightly > >> above the sweet spot still? I just bought 5x 1TB drives and the > >> Samsung spinpoints were the best value - not had any problems with > >> them so far, but don't load them much either. > > > > the 1TB disks specified above have 32MB cache, 5 years > > of manufacturer warranty, they don't suck power, and > > most important, this series has been working for me > > for some time now (the price is roughly 0.12 EUR/GB, > > where e.g. a U320 SCSI disk ranges at 1.2 EUR/GB :) > > > > note that the Samsung F1 Raid costs more than the > > Seagate model, and I'm not convinced about the SpinPoint > > series, as they had bad publicity (overheating and such) > > Here, the Samsung drives are cheaper. As for the risk of overheating, > my Seagate drives are warmer than my Samsung drives, even though the > Samsung disks are under "heavier" load. But whatever you're the most > comfortable with is best... after all, it is your data :-) I'm not strictly against them, just don't have much experience with the Samsung F1 Raid Series ... thanks for the input, Herbert > -- > Daniel Hokka Zakrisson