On Fri, Apr 2, 2010 at 1:15 PM, Christiaan Willemsen <cwillemsen@xxxxxxxxxxxxx> wrote: > Hi there, > > About a year ago we setup a machine with sixteen 15k disk spindles on > Solaris using ZFS. Now that Oracle has taken Sun, and is closing up Solaris, > we want to move away (we are more familiar with Linux anyway). > > So the plan is to move to Linux and put the data on a SAN using iSCSI (two > or four network interfaces). This however leaves us with with 16 very nice > disks dooing nothing. Sound like a wast of time. If we were to use Solaris, > ZFS would have a solution: use it as L2ARC. But there is no Linux filesystem > with those features (ZFS on fuse it not really an option). > > So I was thinking: Why not make a big fat array using 14 disks (raid 1, 10 > or 5), and make this a big and fast swap disk. Latency will be lower than > the SAN can provide, and throughput will also be better, and it will relief > the SAN from a lot of read iops. > > So I could create a 1TB swap disk, and put it onto the OS next to the 64GB > of memory. Then I can set Postgres to use more than the RAM size so it will > start swapping. It would appear to postgres that the complete database will > fit into memory. The question is: will this do any good? And if so: what > will happen? I'd make a couple of RAID-10s out of it and use them for highly used tables and / or indexes etc... -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
