Re: plan time of MASSIVE partitioning ...

On Tue, Sep 7, 2010 at 2:14 PM, Boszormenyi Zoltan <zb@cybertec.at> wrote:
> Hi,
>
> Robert Haas írta:
>> 2010/9/3 PostgreSQL - Hans-Jürgen Schönig <postgres@cybertec.at>:
>>
>>> i tried this one with 5000 unindexed tables (just one col):
>>>
>>> test=# \timing
>>> Timing is on.
>>> test=# prepare x(int4) AS select * from t_data order by id desc;
>>> PREPARE
>>> Time: 361.552 ms
>>>
>>> you will see similar or higher runtimes in case of 500 partitions and a handful of indexes.
>>>
>>
>> I'd like to see (1) a script to reproduce your test environment (as
>> Stephen also requested) and (2) gprof or oprofile results.
>>
>
> attached are the test scripts, create_tables.sql and childtables.sql.
> The following query takes 4.7 seconds according to psql with \timing on:
> EXPLAIN SELECT * FROM qdrs
> WHERE streamstart BETWEEN '2010-04-06' AND '2010-06-25'
> ORDER BY streamhash;

Neat.  Have you checked what effect this has on memory consumption?

Also, don't forget to add it to
https://commitfest.postgresql.org/action/commitfest_view/open

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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