Re: savepoints in 8.3.7 or whatever... - Mailing list pgsql-general

From Alvaro Herrera
Subject Re: savepoints in 8.3.7 or whatever...
Date
Msg-id 20090715181524.GL4551@alvh.no-ip.org
Whole thread Raw
In response to savepoints in 8.3.7 or whatever...  (John R Pierce <pierce@hogranch.com>)
List pgsql-general
John R Pierce wrote:
> we have an app thats doing massive amounts of inserts, batched in
> transactions, multiple concurrent connections (tuned for optimal
> throughput, usually around 1 thread per cpu core plus a couple more).
> occasionally a transaction gets duplicated, and that causes a constraint
> violation which causes the whole transaction to abort unless we wrap
> each insert in a savepoint.
>
> my developers are asking me if there are limits as to how many
> savepoints can be active, etc.   they have run into various such limits
> in oracle.

There's a hard limit of 2^32 savepoints in a transaction, but you'll
probably run into limits before that due to memory constraints (I think
each savepoint will use at least 8kB).  Anyway I suggest you do RELEASE
SAVEPOINT after each insert to ensure resources are released as best as
possible.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.

pgsql-general by date:

Previous
From: Mike Toews
Date:
Subject: Re: PL/Python debugging - line numbers
Next
From: Bill Moran
Date:
Subject: Re: change database