Re: Tunning postgresql - Mailing list pgsql-general

From Mark Kirkwood
Subject Re: Tunning postgresql
Date
Msg-id 3FBB376B.9040900@paradise.net.nz
Whole thread Raw
In response to Tunning postgresql  (Josué Maldonado <josue@lamundial.hn>)
List pgsql-general

Josué Maldonado wrote:

> Hello list,
>
>
> postgresql.conf contains these configurations modified:
>
> shared_buffers = 17000          # min max_connections*2 or 16, 8KB each
> max_fsm_relations = 400     # min 10, fsm is free space map, ~40
> max_fsm_pages = 80000           # min 1000, fsm is free space map, ~6
> max_locks_per_transaction = 64  # min 10
> sort_mem = 16384                # min 64, size in KB
> effective_cache_size = 1700000  # typically 8KB each


These seem pretty reasonable... apart from the effective cache size,
maybe chop off a zero :

effective_cache_size = 170000 # about 1.2G

I wonder if the original setting, 6 times your ram (if my arithmetic is
ok) *may* result in funny optimizer choices....

The thing to do next is examine EXPLAIN outputs for your queries, and
consider what smarter access plans might be possible (e.g. indexes,
partial indexes) and then maybe clever data re-orgizations (e.g.
clusters, trigger based summaries of aggregates) if you still need more
speed.

regards

Mark


pgsql-general by date:

Previous
From: Shridhar Daithankar
Date:
Subject: Re: problem running postmaster
Next
From: Uros
Date:
Subject: Optimizing query