On Sun, 09 Apr 2006 17:00:14 +0100 Simon Riggs <simon@xxxxxxxxxxxxxxx> wrote: > On Sat, 2006-04-08 at 15:10 +0100, Gavin Hamill wrote: > > > SELECTS go to *both* live and test, but only the answers from live > > are sent back to clients - the answers from test are discarded... > > Put log_min_duration_statement = 0 so all SELECTs go to the log. > > Sniff the live log for SELECT statements (plus their live durations), > then route those same statements to the dev box and get a timing from > there also. That way you'll be able to do this without any C coding, > plus you'll have both the live and test elapsed times as a comparison. Ah, having eaten and had my brain finally switch on, I've realised that there's an unfortunate flaw in the plan; only a single process will be executing the SELECT-log which pretty much defeats the purpose of the experiment to simulate identical load patterns on both machines. I might be wrong, but if I just end up grepping for 'SELECT' then feeding the results into psql, then only a single connection will be made to the test server, and all queries will be processed serially on a single CPU, no? Cheers, Gavin.
