Ulrich, > I believe the biggest problem is disc io. Reports for very recent data > are quite fast, these are used very often and therefor already in the > cache. But reports can contain (and regulary do) very old data. In that > case the whole system slows down. To me this sounds like the recent data > is flushed out of the cache and now all data for all queries has to be > fetched from disc.
How large is the database on disk? > My machine has 2GB memory, please find postgresql.conf below. hmmmm ... effective_cache_size? random_page_cost? cpu_tuple_cost? etc. -- Josh Berkus Aglio Database Solutions San Francisco ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq