On 9/21/07, Magnus Hagander <magnus@xxxxxxxxxxxx> wrote: > On Thu, Sep 20, 2007 at 04:33:25PM -0500, Scott Marlowe wrote: > > On 9/20/07, Robert Fitzpatrick <lists@xxxxxxxxxxx> wrote: > > > On Thu, 2007-09-20 at 16:38 -0400, Bill Moran wrote: > > > > In response to Robert Fitzpatrick <lists@xxxxxxxxxxx>: > > > > Why does everyone leave of the IO subsystem? It's almost as if many > > > > people don't realize that disks exist ... > > > > > > > > With 2G of RAM, and a DB that's about 3G, then there's at least a G of > > > > database data _not_ in memory at any time. As a result, disk speed is > > > > important, and _could_ be part of your problem. You're not using RAID > > > > 5 are you? > > > > > > Yes, using RAID 5, not good? RAID 5 with hot fix total of 4 drives. All > > > SATA 80GB drives giving me little under 300GB to work with. > > > > RAID5 optimizes for space, not performance or reliability. It gets > > faster but less reliable as it gets bigger. If you can afford the > > space RAID-10 is generally preferred. > > > > Note however that it is far more important for most general purpose > > servers to have a RAID controller that is both fast by nature (i.e. > > not $50.00) and has battery backed cache with write thru turned on. > > Surely you mean with write thru turned *off*... Or write-back turned on. > But write thru turned on will make your battery unnecessary... Yeah, I meant write back turned on... ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
