Re: Slow dump? - Mailing list pgsql-performance

From Erik Jones
Subject Re: Slow dump?
Date
Msg-id 459A9902.9050100@myemma.com
Whole thread Raw
In response to Re: Slow dump?  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-performance
Tom Lane wrote:
> Erik Jones <erik@myemma.com> writes:
>
>> Hello, we recently migrated our system from 8.1.x to 8.2 and when
>> running dumps have noticed an extreme decrease in speed where the dump
>> is concerned (by more than a factor of 2).
>>
>
> That's odd.  pg_dump is normally pretty much I/O bound, at least
> assuming your tables are sizable.  The only way it wouldn't be is if you
> have a datatype with a very slow output converter.  Have you looked into
> exactly which tables are slow to dump and what datatypes they contain?
> (Running pg_dump with log_min_duration_statement enabled would provide
> useful data about which steps take a long time, if you're not sure.)
>
>             regards, tom lane
>
Well, all of our tables use pretty basic data types: integer (various
sizes), text, varchar, boolean, and timestamps without time zone.  In
addition, other than not having a lot of our foreign keys in place,
there have been no other schema changes since the migration.

--
erik jones <erik@myemma.com>
software development
emma(r)


pgsql-performance by date:

Previous
From: Tom Lane
Date:
Subject: Re: Slow dump?
Next
From: Jeff Davis
Date:
Subject: Re: High update activity, PostgreSQL vs BigDBMS