Dimitri wrote:
Hi Stefan, sorry, I did not have a time to bring all details into the toolkit - but at least I published it instead to tell a "nice story" about :-)
fair point and appreciated. But it seems important that benchmarking results can be verified by others as well...
The client process is a binary compiled with libpq. Client is interpreting a scenario script and publish via SHM a time spent on each SQL request. I did not publish sources yet as it'll also require to explain how to compile them :-)) So for the moment it's shipped as a freeware, but with time everything will be available (BTW, you're the first who asking for sources (well, except IBM guys who asked to get it on POWER boxes, but it's another story :-))
well there is no licence tag(or a copyright notice) or anything als associated with the download which makes it a bit harder than it really needs to be. The reason why I was actually looking for the source is that all my available benchmark platforms are none of the ones you are providing binaries for which kinda reduces its usefulness.
What is good is each client is publishing *live* its internal stats an we're able to get live data and follow any kind of "waves" in performance. Each session is a single process, so there is no contention between clients as you may see on some other tools. The current scenario script contains 2 selects (representing a Read transaction) and delete/insert/update (representing Write transaction). According a start parameters each client executing a given number Reads per Write. It's connecting on the beginning and disconnecting at the end of the test.
well I have seen clients getting bottlenecked internally (like wasting more time in getting rid/absorbing of the actual result than it took the server to generate the answer...). How sure are you that your "live publishing of data" does not affect the benchmark results(because it kinda generates an artifical think time) for example? But what I get from your answer is that you are basically doing one connect/disconnect per client and the testcase you are talking about has 256 clients?
Stefan -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
