Tom Lane <tgl@xxxxxxxxxxxxx> wrote: > I'm wondering about cache effects, ie memory already contains > desired pages in the morning (perhaps as a side-effect of queries > run overnight) and not so much by the evening. If so it's not > clear that additional VACUUM activity would make things better. > > But in any case it's hard to diagnose this without EXPLAIN > ANALYZE output. He did show EXPLAIN OUTPUT results, which showed an index scan in the morning and a seqscan in the evening. He also mentioned that he doubted cache effects amounted to much because the database was 40GB and the machine has 64GB. http://www.postgresql.org/message-id/CAJnnue1x6YYqKbvDQkMTonK62GZSPH-edPR4U7+LOt66M3s_Sw@xxxxxxxxxxxxxx -- Kevin Grittner EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
