Would it be doable, and would it be useful, to try to alternate the directions of table and index scans every time each table/index was fully scanned?
I was thinking that it could help cache performance at various levels in cases where data at the end of a large table, say, that remained in memory after a scan, would otherwise be flushed out by a new scan of the same table. If the next scan of the same table was to go in the other direction, any remains of the last time around that were still in the filesystem cache, buffer pool, hard disk cache etc. would stand a greater chance of being reused. Does that make sense at all? I tried searching the archives for some of the mailing lists but couldn't find anything related. Jeroen ---------------------------(end of broadcast)--------------------------- TIP 6: Have you searched our list archives? http://archives.postgresql.org