Re: Issue for partitioning with extra check constriants

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Josh Berkus <josh(at)agliodbs(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: Issue for partitioning with extra check constriants
Date: 2010-10-04 23:36:40
Message-ID: 9984.1286235400@sss.pgh.pa.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

Josh Berkus <josh(at)agliodbs(dot)com> writes:
>> And your point is? The design center for the current setup is maybe 5
>> or 10 partitions. We didn't intend it to be used for more partitions
>> than you might have spindles to spread the data across.

> Where did that come from? It certainly wasn't anywhere when the feature
> was introduced. Simon intended for this version of partitioning to
> scale to 100-200 partitions (and it does, provided that you dump all
> other table constraints), and partitioning has nothing to do with
> spindles. I think you're getting it mixed up with tablespaces.

[ shrug... ] If Simon thought that, he obviously hadn't done any
careful study of the planner's performance. You can maybe get that far
as long as the partitions have just very simple constraints, but
anything nontrivial won't scale. As you found out.

regards, tom lane

In response to

Browse pgsql-performance by date

  From Date Subject
Next Message Sander, Ingo (NSN - DE/Munich) 2010-10-05 07:23:27 Runtime dependency from size of a bytea field
Previous Message Jeremy Harris 2010-10-04 22:47:16 Re: How does PG know if data is in memory?