On 2013-09-27 13:57:02 -0700, Josh Berkus wrote:
> Andres, Jeff,
>
>
> >> As far as I can tell, the only downside of doing that is that, since hint
> >> bits might be set later, it is possible some dirty pages will get written
> >> unhinted and then re-dirtied by the hint bit setting, when more a
Andres, Jeff,
>> As far as I can tell, the only downside of doing that is that, since hint
>> bits might be set later, it is possible some dirty pages will get written
>> unhinted and then re-dirtied by the hint bit setting, when more aggressive
>> setting would have only one combined dirty write
We have traced this to the *addition* of a two-column index.
> -Original Message-
> From: pgsql-performance-ow...@postgresql.org [mailto:pgsql-
> performance-ow...@postgresql.org] On Behalf Of Jim Garrison
> Sent: Wednesday, September 25, 2013 8:58 AM
> To: pgsql-performance@postgresql.org
We have traced this to the *addition* of a two-column index.
The two tables in question both have single-column indexes on two foreign keys,
say columns A and B. The query joins the two large tables on A and B.
With only the two indexes, the query plan does a bitmap AND on the index scan
re
On Thu, Sep 26, 2013 at 10:14 PM, Merlin Moncure wrote:
> On Thu, Sep 26, 2013 at 6:08 PM, Andres Freund wrote:
>> On 2013-08-27 12:17:55 -0500, Merlin Moncure wrote:
>>> On Tue, Aug 27, 2013 at 10:55 AM, Andres Freund
>>> wrote:
>>> > On 2013-08-27 09:57:38 -0500, Merlin Moncure wrote:
>>> >>
