On Fri, Jul 11, 2008 at 12:21 PM, Greg Smith <[EMAIL PROTECTED]> wrote: > On Fri, 11 Jul 2008, Jeff wrote: > >> I've got a couple boxes with some 3ware 9550 controllers, and I'm less >> than pleased with performance on them.. Sequential access is nice, but start >> seeking around and you kick it in the gut. (I've found posts on the >> internets about others having similar issues). > > Yeah, there's something weird about those controllers, maybe in how stuff > flows through the cache, that makes them slow in a lot of situations. The > old benchmarks at > http://tweakers.net/reviews/557/21/comparison-of-nine-serial-ata-raid-5-adapters-pagina-21.html > show their cards acting badly in a lot of situations and I haven't seen > anything else since vindicating the 95XX models from them. > >> My last box with a 3ware I simply had it in jbod mode and used sw raid and >> it smoked the hw. > > That is often the case no matter which hardware controller you've got, > particularly in more complicated RAID setups. You might want to consider > that a larger lesson rather than just a single data point. > >> Anyway, anybody have experience in 3ware vs Areca - I've heard plenty of >> good anecdotal things that Areca is much better, just wondering if anybody >> here has firsthand experience. It'll be plugged into about 8 10k rpm sata >> disks. > > Areca had a pretty clear performance lead for a while there against 3ware's > 3500 series, but from what I've been reading I'm not sure that is still true > in the current generation of products. Check out the pages starting at > http://www.tomshardware.com/reviews/SERIAL-RAID-CONTROLLERS-AMCC,1738-12.html > for example, where the newer Areca 1680ML card just gets crushed at all > kinds of workloads by the AMCC 3ware 9690SA. I think the 3ware 9600 series > cards have achieved or exceeded what Areca's 1200 series was capable of, > while Areca's latest generation has slipped a bit from the previous one.
>From my experience, the Areca controllers are difficult to operate. Their firmware is, frankly, garbage. In more than one instance we have had the card panic when a disk fails, which is obviously counter to the entire purpose of a RAID. We finally removed the Areca controllers from our database server and replaced them with HP P800s. -jwb -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance