Re: slow joining very large table to smaller ones

On Jul 15, 2005, at 9:09 AM, Dan Harris wrote:

>
> On Jul 14, 2005, at 10:12 PM, John A Meinel wrote:
>
>>
>> My biggest question is why the planner things the Nested Loop
>> would be
>> so expensive.
>> Have you tuned any of the parameters? It seems like something is
>> out of
>> whack. (cpu_tuple_cost, random_page_cost, etc...)
>>
>>
>
> here's some of my postgresql.conf.  Feel free to blast me if I did
> something idiotic here.
>
> shared_buffers = 50000
> effective_cache_size = 1348000
> random_page_cost = 3
> work_mem = 512000
> max_fsm_pages = 80000
> log_min_duration_statement = 60000
> fsync = true ( not sure if I'm daring enough to run without this )
> wal_buffers = 1000
> checkpoint_segments = 64
> checkpoint_timeout = 3000
>
>
> #---- FOR PG_AUTOVACUUM --#
> stats_command_string = true
> stats_row_level = true
>

Sorry, I forgot to re-post my hardware specs.

HP DL585
4 x 2.2 GHz Opteron
12GB RAM
SmartArray RAID controller, 1GB hardware cache, 4x73GB 10k SCSI in
RAID 0+1
ext2 filesystem

Also, there are 30 databases on the machine, 27 of them are identical
schemas.