Mike Leahy wrote:
Mark/List,
I just replaced my postgresql.conf with the default copy that appears in
/etc/postgresql/8.4/main/ after a fresh install. The performance is pretty
much the same as before (maybe even about 400 ms worse than before).
Is there anything else I should try?
Mike
Hi Mark,
I set effective_cache_size to 3072mb, and shared_buffers to 1024mb (as my
system
has a total of 4gb). This only slightly (if at all) improves the performance,
maybe reducing the query by somewhere around 500 ms (down to ~14700 ms). All
other parameters in the postgresql.conf are
...@postgis.refractions.net
[mailto:postgis-users-boun...@postgis.refractions.net] On Behalf Of Mike
Leahy
Sent: Wednesday, March 31, 2010 1:17 PM
To: Mark Cave-Ayland
Cc: PostGIS Users Discussion
Subject: Re: [postgis-users] Nested loop join = very bad performance
Hi Mark,
I set effective_cache_size to 3072mb
-Original Message-
From: postgis-users-boun...@postgis.refractions.net
[mailto:postgis-users-boun...@postgis.refractions.net] On Behalf Of Mike
Leahy
Sent: Wednesday, March 31, 2010 1:17 PM
To: Mark Cave-Ayland
Cc: PostGIS Users Discussion
Subject: Re: [postgis-users] Nested loop
Mike Leahy wrote:
Is this something that should be looked into, or should I just incorporate the
workaround of disabling nested loop joins into my code?
I find that generally PostgreSQL is fairly good at its estimates unless
someone has already tried to tune the database. Have you changed
Hi Mark,
I don't recall making any changes...at least not until the error I encountered
last week cropped up - but I think I reversed those changes (I will double-
check tonight). But I think I have encountered performance problems with this
query before on other systems - I had originally
Hello list,
Following up from the bug that was successfully resolved last week
(http://trac.osgeo.org/postgis/ticket/469), I've found that nested loop joins
are actually causing very bad performance with my queries.
Thanks to the observations of Leo and Regina in that discussion, I have found
Sorry all...here's the explain output I promised in my previous message...
On Sunday 28 March 2010 11:57:01 Mike Leahy wrote:
Hello list,
Following up from the bug that was successfully resolved last week
(http://trac.osgeo.org/postgis/ticket/469), I've found that nested loop
joins are
