Re: Pre-creating partitions incurs insert penalty

Nope, they're independent of each other.

On Thu, May 28, 2009 at 8:49 PM, Anj Adu <fotographs(at)gmail(dot)com> wrote:
> Thanks..I'll rewrite the rules as triggers. Would that in any way impact
> constraint exclusion for select statements ?..I assume not.
>
> On Thu, May 28, 2009 at 5:46 PM, Scott Marlowe <scott(dot)marlowe(at)gmail(dot)com>
> wrote:
>>
>> Yeah, rules have more overhead the more partitions you have, whereas
>> triggers do not.  If you can switch to triggers you'd like see better
>> performance, but be aware that plpgsql is kind of retarded when it
>> comes to doing anything fancy with triggers.
>>
>> On Thu, May 28, 2009 at 6:43 PM, Anj Adu <fotographs(at)gmail(dot)com> wrote:
>> > Partitioning is implemented via rules and check constraints to ensure
>> > partition integrity.
>> >
>> > On Thu, May 28, 2009 at 5:21 PM, Scott Marlowe <scott(dot)marlowe(at)gmail(dot)com>
>> > wrote:
>> >>
>> >> On Thu, May 28, 2009 at 5:22 PM, Anj Adu <fotographs(at)gmail(dot)com> wrote:
>> >> > I noticed a very strange performance issue after I pre-create daily
>> >> > partitions for the next month on a table that has a very large insert
>> >> > volume
>> >> > (30 million a day). After the partitions are created..the inserts
>> >> > seem
>> >> > to
>> >> > slow down. I verifiied that this was the issue by dropping the
>> >> > partitions...When I dropped the pre-created partitions..the
>> >> > performance
>> >> > issue disappeared. Looks like you cannot have too many partitions (in
>> >> > this
>> >> > case..I had a total of 35 partitions when the performance issue was
>> >> > noticed)
>> >>
>> >> How are you enforcing partiitoning on your inserts?  Via app
>> >> knowledge, triggers, or rules?  I'd expect rules might have a penalty
>> >> with more partitions, but not expect it from app or trigger based
>> >> partitioning.
>> >
>> >
>>
>>
>>
>> --
>> When fascism comes to America, it will be intolerance sold as diversity.
>
>

--
When fascism comes to America, it will be intolerance sold as diversity.