Re: Monitoring and insight into NOTIFY queue

On Fri, Feb 19, 2016 at 8:01 AM, Jiří Hlinka <jiri(dot)hlinka(at)gmail(dot)com> wrote:
> Hello,
>
> I'd like to ask you whether there is a way how to monitor and log details
> about NOTIFY queue? What do you use for this prupose?
>
> In the official documentation I'm unable to find a way how to monitor NOTIFY
> queue in more detail, at least size of this queue, which is critical in case
> of filling up the queue, which will lead to stopping the NOTIFY queue
> functionality.

It used to be possible to do this with the (slow, locky) table based
notification mechanism. Unfortunately FWICT it isn't now and we
really ought to expand functionality in that area.

I will say though that async notification should thought of as 'best
effort'...if you are laying essential communication processes on top
of it you need to have the listener respond and be prepare to retry.
Another thing, queue size paranoia aside (which is a good way to
consider things) I've never had the queue bust on me and I've beat on
it pretty hard.

merlin