Bruce Momjian <[EMAIL PROTECTED]> writes: > Well, except for bind, all the log output display is zero cost, just a > printf(), as I remember. The only cost that is significant, I think, is > the timing of the query, and that is happening for all the setttings > discussed.
On a machine with slow gettimeofday(), measuring duration at all is going to hurt, but apparently that is not Guillaume's situation --- what's costing him is sheer log volume. And remember that the slow-gettimeofday problem exists mainly on cheap PCs, not server-grade hardware. Based on his experience I'm prepared to believe that there is a use-case for logging just the duration for short queries. It seems like we should either remove the separate log_duration boolean or make it work as he suggests. I'm leaning to the second answer now. What's your vote? regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match