On Thu, Sep 24, 2009 at 8:22 AM, Jared Beck wrote:
> Should we try to improve statistics collection for that column
> (variableid) by using ALTER TABLE ... ALTER COLUMN ... SET STATISTICS?
It's worth a try, but I'm not sure it's going to help much. The LIKE
condition is hard for the planner to e
On Wed, Sep 23, 2009 at 10:35 PM, Tom Lane wrote:
>
> One thing that is hobbling the performane on 8.4 is that you have
> work_mem set to only 1MB
>
> Other things you might try include increasing join_collapse_limit
> to 12 or so, and reducing random_page_cost.
>
> Another thing to look into is w
> Hello postgres wizards,
>
> We recently upgraded from 8.1.5 to 8.4
> We have a query (slow_query.sql) which took about 9s on 8.1.5
> On 8.4, the same query takes 17.7 minutes.
>
> The code which generated this query is written to support the
> calculation of arbitrary arithmetic expressions acros
Jared Beck writes:
> Hello postgres wizards,
> We recently upgraded from 8.1.5 to 8.4
> We have a query (slow_query.sql) which took about 9s on 8.1.5
> On 8.4, the same query takes 17.7 minutes.
One thing that is hobbling the performane on 8.4 is that you have
work_mem set to only 1MB (you had it
Hello postgres wizards,
We recently upgraded from 8.1.5 to 8.4
We have a query (slow_query.sql) which took about 9s on 8.1.5
On 8.4, the same query takes 17.7 minutes.
The code which generated this query is written to support the
calculation of arbitrary arithmetic expressions across "variables"
essage
From: Jared Beck
To: pgsql-performance@postgresql.org
Cc: Leon Miller-Out
Sent: Wednesday, September 23, 2009 12:53:15 PM
Subject: [PERFORM] Slow query after upgrade to 8.4
Hello postgres wizards,
We recently upgraded from 8.1.5 to 8.4
We have a query (slow_query.sql) which took about 9s
Hello postgres wizards,
We recently upgraded from 8.1.5 to 8.4
We have a query (slow_query.sql) which took about 9s on 8.1.5
On 8.4, the same query takes 17.7 minutes.
The code which generated this query is written to support the
calculation of arbitrary arithmetic expressions across "variables"