On Jun 18, 2004, at 7:31 AM, Gary Cowell wrote:
The explain output on postgres shows the same
execution with a scan on vers and a sort but the query
time is 78.6 seconds.
The explain output on postgres shows the same
execution with a scan on vers and a sort but the query
time is 78.6 seconds.
It could be a case of the caches being empty
Oracle but I think I've configured comparible
buffering and sort area sizes, certainly there isn't
much physical IO going on in either case.
Configuring PG like Oracle isn't the best thing in the world. Thebuffering and sort area sizes, certainly there isn't
much physical IO going on in either case.
general PG philosophy is to let the OS do all the caching & buffering
- this is reversed in the Oracle world. In 7.4 the rule of thumb is no
more than 10k shared_buffers.. beyond that the overhead of maintaining
it becomes excessive. (This isn't really the case in 7.5)
Curiously, what are your sort_mem and shared_buffers settings?
