Re: fixing LISTEN/NOTIFY

On Thu, 2005-06-10 at 01:14 -0400, Tom Lane wrote:
> The idea of blocking during commit until shmem becomes available might
> work.  There's some issues here about transaction atomicity, though:
> how do you guarantee that all or none of your notifies get sent?
> (Actually, supposing that the notifies ought to be sent post-commit,
> "all" is the only acceptable answer.  So maybe you just never give up.)

Yeah, I think that would work. We could also write to shared memory
before the commit proper, and embed an XID in the message to allow other
backends to determine when/if to fire the notification.

However, I don't really like the idea of blocking the backend for a
potentially significant amount of time in a state half-way between
"committed" and "ready for the next query".

-Neil