Another RAID controller recommendation question
Another RAID controller recommendation question
От:
David Boreham <david_list@boreham.org>
Дата:
We're looking to deploy a bunch of new machines. Our DB is fairly small and write-intensive. Most of the disk traffic is PG WAL. Historically we've avoided RAID controllers for various reasons, but this new deployment will be done with them (also for various reasons ;) We like to use white-boxish machines and we run CentOS. This would be a good example of the kind of machine we'd buy: http://www.newegg.com/Product/Product.aspx?Item=N82E16816101339 manufacturer page : http://www.supermicro.com/products/system/1U/6016/SYS-6016T-URF4_.cfm?UIO=N these boxes have a proprietary controller slot, with these cards: http://www.supermicro.com/products/nfo/UIO.cfm#Adapters specifically this LSI-based one which seems to be the newest/fastest, with BBWBC: http://www.supermicro.com/products/accessories/addon/AOC-USAS2LP-H8iR.cfm I'd be interested to hear any options good or bad on these controllers, or ideas for alternatives. These machines are operated in a lights-out mode, and will handle heavy constant load (hundreds of write txn/s) with 15K SAS drives in a RAID-1 setup (2 drives, or 2 + 2 with data and WAL split between spindle groups). Thanks!
Re: Another RAID controller recommendation question
От:
Greg Smith <greg@2ndQuadrant.com>
Дата:
On 06/18/2011 02:46 AM, David Boreham wrote: > > We're looking to deploy a bunch of new machines. > Our DB is fairly small and write-intensive. Most of the disk > traffic is PG WAL. Historically we've avoided > RAID controllers for various reasons, but this new deployment will be > done with them (also for various reasons ;) If the traffic is heavy on WAL, avoiding RAID controllers isn't a great practice. They're by far the best way possible to speed that up. > http://www.newegg.com/Product/Product.aspx?Item=N82E16816101339 > manufacturer page : > http://www.supermicro.com/products/system/1U/6016/SYS-6016T-URF4_.cfm?UIO=N > This a solid basic server model. The Intel 5520 chipset they're built on is nice and fast if you load it up with a bunch of RAM. > these boxes have a proprietary controller slot, with these cards: > http://www.supermicro.com/products/nfo/UIO.cfm#Adapters > specifically this LSI-based one which seems to be the newest/fastest, > with BBWBC: > http://www.supermicro.com/products/accessories/addon/AOC-USAS2LP-H8iR.cfm I don't really like the whole proprietary controller slot thing if it can be avoided. We seem to have a lot of customers buying from Dell recently, and it's partly because they've made it pretty straightforward to swap out their PERC controller. That makes troubleshooting a broken server easier, spare parts are simple to manage, lots of advantages. You almost need to stock your own spares for things like the RAID cards if they're these propriety slot ones, because you're unlikely to find one in an emergency. That said, the card itself looks like plain old simple LSI MegaRAID. Get the battery backup unit, check the battery and cache policy to make sure they're sane, and learn how to use megaci to monitor it. Fast and generally trouble free after that initial setup time investment. > These machines are operated in a lights-out mode, and > will handle heavy constant load (hundreds of write txn/s) with 15K SAS > drives > in a RAID-1 setup (2 drives, or 2 + 2 with data and WAL split between > spindle groups). If you can try to measure the exact ratio of database to WAL traffic here, that might help guide which of these configurations makes more sense. Hard to answer in a general way. -- Greg Smith 2ndQuadrant US greg@2ndQuadrant.com Baltimore, MD PostgreSQL Training, Services, and 24x7 Support www.2ndQuadrant.us "PostgreSQL 9.0 High Performance": http://www.2ndQuadrant.com/books
Re: Another RAID controller recommendation question
От:
David Boreham <david_list@boreham.org>
Дата:
On 6/18/2011 1:22 AM, Greg Smith wrote: > > That said, the card itself looks like plain old simple LSI MegaRAID. > Get the battery backup unit Thanks. Dell's web site drives me insane, and it appears I can save 20% or more by going white-box. One thing I don't understand is why is the BBU option never available with "integrated" LSI controllers? It appears that anything with a BBU/WBC capability immediately adds $700 or so to the machine price.
Re: Another RAID controller recommendation question
От:
Scott Ribe <scott_ribe@elevated-dev.com>
Дата:
On Jun 19, 2011, at 12:33 AM, David Boreham wrote: > One thing I don't understand is why is the BBU option never available with "integrated" LSI controllers? Because "integrated" means it's on the mobo to save costs. -- Scott Ribe scott_ribe@elevated-dev.com http://www.elevated-dev.com/ (303) 722-0567 voice
