yoav x <yoav112003@xxxxxxxxx> writes: > Are there any tuning parameters that can be changed to speed these > queries? Or are these queries especially tuned to show MySQL's > stgrenths? The latter. I've ranted about this before --- there are both obvious and subtle biases in that benchmark. The last time I spent any time with it, I ended up testing with these nondefault settings: shared_buffers = 10000 work_mem = 100000 maintenance_work_mem = 100000 fsync = false checkpoint_segments = 30 max_locks_per_transaction = 128 (fsync = false is pretty bogus for production purposes, but if you're comparing to mysql using myisam tables, I think it's a reasonably fair basis for comparison, as myisam is certainly not crash-safe. It'd be interesting to see what mysql's performance looks like on this test using innodb tables, which should be compared against fsync = true ... but I don't know how to change it to get all the tables to be innodb.) Also, on some of the tests it makes a material difference whether you are using C locale or some other one --- C is faster. And make sure you have a recent version of DBD::Pg --- a year or two back I recall seeing the perl test program eating more CPU than the backend in some of these tests, because of inefficiencies in DBD::Pg. IIRC, with these settings PG 8.0 seemed to be about half the speed of mysql 5.0 w/myisam, which is probably somewhere in the ballpark of the truth for tests of this nature, ie, single query stream of fairly simple queries. If you try concurrent-update scenarios or something that stresses planning ability you may arrive at different results though. I have not retested with more recent versions. regards, tom lane
