> > You were running the test on the very memory-depend machine. > >> shared_buffers = 4GB / The scaling factor is 50, 800MB of data. > > Thet would be why the patch did not work. I tested it with DBT-2, 10GB of > > data and 2GB of memory. Storage is always the main part of performace here, > > even not in checkpoints. > > Yes, I used half the size of RAM as the shared buffers, which is > reasonable. And I cached all the data.
For pg, half RAM for shared_buffers is too much. The ratio is good for other db software, that does not use the OS cache. Andreas ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq