When I went to 7.4.3 (Slackware 9.1) w/ JDBC, the improvements are that it doesn't initially take much memory (have 512M) and didn't swap. I ran a full vaccum and a cluster before installation, however speed degaded to 1 *second* / update of one row in 150 rows of data, within a day! pg_autovacuum now gives excellent performance however it is taking 66M of swap; only 270k cached.
Are you saying that your system stays fast now that you are using pg_autovacuum, but pg_autovacuum is using 66M of memory? Please clarify, I'm not sure what question you want an answered.
Matthew
---------------------------(end of broadcast)--------------------------- TIP 9: the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
