Gregory Stark wrote: > "Magnus Hagander" <[EMAIL PROTECTED]> writes: > >>> What 3 columns? In-memory sorts, on-disk sorts, and on-disk size? >>> (Sum of how much spilled to disk). >> I was thinking in-mem sorts, on-disk sorts, limited-by-LIMIT sorts (that >> would be the new feature..) > > Tom's code distinguished in-memory, top-N, on-disk with final merge postponed, > and on-disk with materialized result. Four categories. But I think the > distinction between the two types of in-memory and the two types of on-disk > sorts is only really useful when you're looking at an individual query. And > even then probably only useful to a Postgres hacker, not a DBA.
Missed the two on-disk distinctions, yeah. But you're probably right that on-disk vs in-memory is enough, the interesting thing is to get indications on when you hit disk given what it does for performance. > It seems like it would be more useful to just break it down into in-memory and > on-disk but for each give number of sorts, number of tuples, and space used. > > What would be really handy is breaking this down by table -- probably that > would only be possible when the sort is sorting directly a table scan. I don't > even know how easy it would be to get that information. And how would you deal with the data that's sorting the result of a join or something like that - makes things a lot more complicated ;) And the original question remains, 8.3 or 8.4... //Magnus ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq