"Marc G. Fournier" <scrappy@postgresql.org> writes:
> do we maintain anything anywhere for this? mainly, some way of
> determining # of 'sorts to disk' vs 'sort in memory', to determine whether
> or not sort_mem is set to a good value?
As of 8.1 you could turn on trace_sort to collect some data about this.
Looking at the code, I notice that the messages are all emitted at level
NOTICE. Perhaps that was not such a good idea --- it'd be pretty much
in-your-face if it were on all the time. Does anyone think it'd be a
good idea to emit the trace_sort messages at level LOG, instead?
regards, tom lane