Search Postgresql Archives

Re: Optimise PostgreSQL for fast testing

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 23/02/2012, at 7:35 PM, Marti Raudsepp wrote:

> If you have lots of very simple queries, then usually much of the
> overhead is in query planning. There are a few tricks to dumb down the
> planner to make it faster -- although that may come at the cost of
> slowing down execution.
> 
> * If your queries use joins at all, you can reduce planning overhead
> by setting join_collapse_limit=1 and from_collapse_limit=1 or some
> other low number.
> * Set default_statistics_target=5 or another low number and run
> ANALYZE on the whole database.
> * Set enable_bitmapscan=off, enable_material=off,
> enable_mergejoin=off, enable_hashjoin=off -- this will prevent the
> planner for trying certain kinds of plans in the first place.
> 
> Just for the heck of it, you might gain a bit by setting
> track_activities=off, update_process_title=off

Thanks a lot Marti.
After I've applied these settings I couldn't see major improvement over fsync=off. It was pretty much within the error margin.

But you're right that most of the queries are simple and I hope this will work a little bit faster on small runs (like a single test suite).
Will definitely keep an eye on these settings.

So far fsync=off is the best I could get.

Thanks one more time for the help.

Cheers.
-- 
Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general



[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Postgresql Jobs]     [Postgresql Admin]     [Postgresql Performance]     [Linux Clusters]     [PHP Home]     [PHP on Windows]     [Kernel Newbies]     [PHP Classes]     [PHP Books]     [PHP Databases]     [Postgresql & PHP]     [Yosemite]
  Powered by Linux