Re: auto_explain WAS: RFC: Timing Events

Greg,

First off, let me again praise the great work you and Peter are doing in
this area.

> Modeling this on pg_stat_statements includes the hope of packaging it as
> an extension with minor core hooks, and the idea that there would be a
> fixed size list of timing events available at any time.  Consider it a
> FIFO queue built using a circular buffer.  Dump events into there and
> provide a way to view them.  If some fall out before they're
> analyzed/saved, that doesn't seem a problem for now.

Agreed.

>  If you want 100%
> durable, the log is still available.  Eventually I'd like a consumer for
> these that wrote them to a history table as an option, but that seems a
> second priority after getting them into memory in the first place.

Yes, and easy for users/tools to implement once the basic data is out there.

>  I'd
> like that consumer thing for pg_stat_statements too, but so far we're
> getting by without it.  It seems like something that might benefit from
> the in-core queuing work one day too.

Well, we could actually use such a thing in general, and not just for
the timing events.  For example, it would be really useful to be able to
see, for example, pg_stat_user_tables from 2 days ago to estimate table
growth and activity, or pg_stat_replication from 10 minutes ago to
average replication lag.  There was a plug-in tool for this, I think
Itagaki developed it.  Anyone remember what/where it is?