Stefan Kaltenbrunner wrote: > Bruce Momjian wrote: > > OK, based on reports I have seen, generally stats_query_string adds 50% > > to the total runtime of a "SELECT 1" query, and the patch reduces the > > overhead to 25%. > > that is actually not true for both of the platforms(a slow OpenBSD > 3.9/x86 and a very fast Linux/x86_64) I tested on. Both of them show > virtually no improvement with the patch and even worst it causes > considerable (negative) variance on at least the Linux box.
I see the results I suggested on OpenBSD that you reported. > OpenBSD 3.9-current/x86: > > without stats: > 0m6.79s real 0m1.56s user 0m1.12s system > > -HEAD + stats: > 0m10.44s real 0m2.26s user 0m1.22s system > > -HEAD + stats + patch: > 0m10.68s real 0m2.16s user 0m1.36s system and I got similar results reported from a Debian: Linux 2.6.16 on a single processor HT 2.8Ghz Pentium compiled with gcc 4.0.4. > > real 0m3.306s > > real 0m4.905s > > real 0m4.448s I am unclear on the cuase for the widely varying results you saw in Debian. -- Bruce Momjian http://candle.pha.pa.us EnterpriseDB http://www.enterprisedb.com + If your life is a hard drive, Christ can be your backup. + ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org