On 2015-07-08 13:46:53 -0500, Merlin Moncure wrote: > On Wed, Jul 8, 2015 at 12:48 PM, Craig James <cjames@xxxxxxxxxxxxxx> wrote: > > On Tue, Jul 7, 2015 at 10:31 PM, Joshua D. Drake <jd@xxxxxxxxxxxxxxxxx> > >> Using Apache Fast-CGI, you are going to fork a process for each instance > >> of the function being executed and that in turn will use all CPUs up to the > >> max available resource. > >> > >> With PostgreSQL, that isn't going to happen unless you are running (at > >> least) 8 functions across 8 connections. > > > > > > Well, right, which is why I mentioned "even with dozens of clients." > > Shouldn't that scale to at least all of the CPUs in use if the function is > > CPU intensive (which it is)? > > only in the absence of inter-process locking and cache line bouncing. And addititionally memory bandwidth (shared between everything, even in the numa case), cross socket/bus bandwidth (absolutely performance critical in multi-socket configurations), cache capacity (shared between cores, and sometimes even sockets!). -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
