Re: How to force Nested Loop plan?

Ron Johnson writes:
> Dumb question: given your out-of-the-box satisfaction, could it be
> that postgresql.conf hasn't been tweaked?

Here are the modified values:

shared_buffers = 8000
wal_buffers = 80
sort_mem = 32000
effective_cache_size = 400000
random_page_cost = 4
autocommit = false
timezone = UTC

I had run a test with effective_cache_size to high value to see what
would happen.  Also adjusted random_page_cost:

random_page_cost effective_cache_size    elbow
    4                    40000            675
    .5                    40000            592
    .1                    40000            392
    4                    1000            30

My conclusion is that random_page_cost should be left alone and
effective_cache_size higher is better.

BTW, the hardware is 2 x 2.4ghz Xeon, 1.2GB, SCSI (linux software
raid) with 10K disks.  This is close to the production box.  Although
we are planning on adding more memory to production.

Rob