On Thu, 2006-06-08 at 17:21 -0400, Tom Lane wrote: > Alvaro Herrera <[EMAIL PROTECTED]> writes: > > Tried on two machines. The first (Turion64 laptop) gives 44-45 ms for > > the SELECT, and 50-51 ms for the EXPLAIN ANALYZE. > > > The second machine, desktop Celeron 533, gives 197-200 ms for the SELECT > > and 788-790 for the EXPLAIN ANALYZE. I guess this is the reproduction > > you were looking for. > > Do you have oprofile installed on these? Comparing oprofile results > might give some more insight where the time is going.
On my office PC the overhead from EA is about 20%. stracing a backend, I also notice that on a 1.5 million row table we make only 39158 calls to gettimeofday, on a table of 24591 blocks. I'm thinking that the instrumentation overhead has been reduced as a result of the page-at-a-time heap scans we now have? -- Simon Riggs EnterpriseDB http://www.enterprisedb.com ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq
