Re: [PATCH] V3: Idle in transaction cancellation

Kevin Grittner <kevin.grittner@wicourts.gov>

From: "Kevin Grittner" <Kevin.Grittner@wicourts.gov>
To: "Andres Freund" <andres@anarazel.de>, "Tom Lane" <tgl@sss.pgh.pa.us>
Cc: "Greg Smith" <greg@2ndquadrant.com>, "Alvaro Herrera" <alvherre@commandprompt.com>, "Robert Haas" <robertmhaas@gmail.com>, "pgsql-hackers" <pgsql-hackers@postgresql.org>
Date: 2010-12-23T22:04:43Z
Lists: pgsql-hackers
Andres Freund <andres@anarazel.de> wrote:
 
> I will try to read the thread and make a proposal for a more
> carefull implementation - just not today... I think the results
> would be interesting...
 
FWIW, the SSI patch that Dan and I are working on can't have a
guarantee that it is immediately safe to retry a transaction which
rolls back with a serialization failure (without potentially failing
again on exactly the same set of transactions) unless there is a
capability such as this "Idle in transaction cancellation" patch
would provide.  Safe immediate retry would be a nice guarantee for
SSI to provide.
 
That being the case, we may not be able to generate the final form
of the SSI patch until a patch for this issue is applied.  Obviously
I know that nobody is in a position to make any promises on this,
but I just thought I'd let people know that this issue could
possibly be on the critical path to a timely release -- at least if
that release will include SSI with the safe retry guarantee.  (At
least when I'm planning for a release, I like to know such
things....)
 
-Kevin