On 3/25/09 9:28 PM, "Mark Kirkwood" <mar...@paradise.net.nz> wrote:
> I wrote: >> Scott Marlowe wrote: >> >>> >>> Can you try changing the chunksize on the test box you're testing on >>> to see if that helps? >>> >>> >> >> Yes - or I am hoping to anyway (part of posting here was to collect >> some outside validation for the idea). Thanks for your input! >> > > Rebuilt with 64K chunksize: > > transaction type: TPC-B (sort of) > scaling factor: 100 > number of clients: 24 > number of transactions per client: 12000 > number of transactions actually processed: 288000/288000 > tps = 866.512162 (including connections establishing) > tps = 866.651320 (excluding connections establishing) > > > So 64K looks quite a bit better. I'll endeavor to try out 256K next week > too. Just go all the way to 1MB, md _really_ likes 1MB chunk sizes for some reason. Benchmarks right and left on google show this to be optimal. My tests with md raid 0 over hardware raid 10's ended up with that being optimal as well. Greg's notes on aligning partitions to the chunk are key as well. > > Mark > > -- > Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-performance > -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
