Re: Cancelling idle in transaction state

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>
To: Joachim Wieland <joe@mcknight.de>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Hannu Krosing <hannu@2ndquadrant.com>, James Pye <lists@jwp.name>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2009-12-31T11:10:35Z
Lists: pgsql-hackers
On Thu, 2009-12-24 at 21:38 +0100, Joachim Wieland wrote:
> On Sun, Dec 6, 2009 at 4:23 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> > We are using NOTICE, not NOTIFY, assuming that we use anything at all
> > (which I still regard as unnecessary).  Please stop injecting confusion
> > into the discussion.
> 
> Attached is a minimal POC patch that allows to cancel an idle
> transaction with SIGINT. The HS patch also allows this in its current
> form but as Simon points out the client gets out of sync with it.
> 
> The proposal is to send an additional NOTICE to the client and abort
> all open transactions and subtransactions (this is what I got from the
> previous discussion).

This all works and I'm looking to post a reviewed patch soon.

> I had to write an additional function AbortAnyTransaction() which
> aborts all transactions and subtransactions and leaves the transaction
> in the aborted state, is there an existing function to do this?

My use of AbortOutOfAnyTransaction() was what caused the
problem-I-couldn't-solve. It aborted too far, confusing clients.
Joachim's function does the right thing and leaves the transaction state
correctly, so that clients don't get confused. 

Problem solved, thanks Joachim.

-- 
 Simon Riggs           www.2ndQuadrant.com