On Fri, Feb 20, 2009 at 2:35 PM, Robert Haas <robertmh...@gmail.com> wrote:
> > First of all, you need to do some research on the benchmark kit itself, > > rather than blindly downloading and using one. BenchmarkSQL has > significant > > bugs in it which affect the result. I can say that authoritatively as I > > worked on/with it for quite awhile. Don't trust any result that comes > from > > BenchmarkSQL. If you fix the bugs, Oracle (out of the box in OLTP > config) > > will come out 60%. > > 60% what? Faster than PG 8.3-dev with 100 warehouses (when I last tested it). > > Oracle comes out twice as fast as PG on Linux. And, unless you're using > a > > significant number of warehouses, MySQL+InnoDB will come out better than > PG > > as well. > > I can believe that MySQL could come out faster than PG because I've > had previous experience with it being blindingly fast. Of course I've > also had experience with it having amazingly poor data integrity. That was MySQL+InnoDB. I haven't really had any integrity problems in that configuration. > I would be pretty surprised if Oracle were in general twice as fast as > PG - what are they doing that much better than what we're doing? I > could certainly imagine it being true in cases that rely on specific > features we lack (e.g. join removal)? DIO + AIO + multiple DBWR processes + large buffer cache + properly sized logs/log buffers makes a big difference. There are also several other concurrency-related tunables which contribute to it as well. -- Jonah H. Harris, Senior DBA myYearbook.com
