Re: pg_listener in 9.0

On 11-06-01 09:30 AM, Christopher Browne wrote:
> On Wed, Jun 1, 2011 at 8:29 AM, Dave Page<dpage(at)pgadmin(dot)org> wrote:
>> On Wed, Jun 1, 2011 at 12:27 PM, Andrew Dunstan<andrew(at)dunslane(dot)net> wrote:
>>> The whole point of the revamp was that pg_listener was a major performance
>>> bottleneck and needed to go, and without it being gone we would not have got
>>> notification payloads.
>> Yeah, I know why it was replaced. That doesn't mean we cannot provide
>> an alternative interface to the same info though (other things might
>> of course).
>>
>>> I suspect you're pretty much out of luck.
>> Not me - our users.
> Note that in Slony 2.1, there's a table called sl_components, which is
> used to capture the state of the various database connections,
> checking in as the various threads do their various actions.
>
> Also, slon and slonik try to report their respective application, so
> it can be reported on pg_stat_activity.

Slony 2.1 also sets application_name.

If this were a big deal for pgAdmin we could consider backporting the
application_name change to 2.0.x for users running against 9.0.

Slony also has a table called sl_nodelock that each slon process writes
adds a row for on startup. This includes the backend pid() for one of
the connections. Slony 1.2, 2.0 and 2.1 all use sl_nodelock