On Wed, May 1, 2013 at 10:26 AM, ktm@xxxxxxxx <ktm@xxxxxxxx> wrote: > On Wed, May 01, 2013 at 04:07:55PM +0000, Anne Rosset wrote: >> Hi Ken, >> Thanks for your answer. My test is actually running with jboss 7/jdbc and the connection pool is defined with min-pool-size =10 and max-pool-size=400. >> >> Why would you think it is an issue with the connection pool? >> >> Thanks, >> Anne >> > > Hi Anne, > > You want to be able to run as many jobs productively at once as your hardware is > capable of supporting. Usually something starting a 2 x number of CPUs is best. > If you make several runs increasing the size of the pool each time, you will > see a maximum throughput somewhere near there and then the performance will > decrease as you add more and more connections. You can then use that sweet spot. > Your test harness should make that pretty easy to find. Here's a graph of tps from pgbench on a 48 core / 32 drive battery backed cache RAID machine: https://plus.google.com/u/0/photos/117090950881008682691/albums/5537418842370875697/5537418902326245874 Note that on that machine, the peak is between 40 and 50 clients at once. Note also the asymptote levelling off at 2800tps. This is a good indication of how the machine will behave if overloaded / connection pooling goes crazy etc. So yeah I suggest Anne do what you're saying and chart it. It should be obvious where the sweet spot is. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
