Re: proposal for 9.5: monitoring lock time for slow queries

Pavel Stehule wrote:
> 2014-08-13 15:22 GMT+02:00 MauMau <maumau307@gmail.com>:

> > I didn't mean performance statistics data to be stored in database tables.
> > I just meant:
> >
> > * pg_stat_system_events is a view to show data on memory, which returns
> > one row for each event across the system.  This is similar to
> > V$SYSTEM_EVENT in Oracle.
> >
> > * pg_stat_session_events is a view to show data on memory, which returns
> > one row for each event on one session.  This is similar to V$SESSION_EVENT
> > in Oracle.
> >
> > * The above views represent the current accumulated data like other
> > pg_stat_xxx views.
> >
> > * EXPLAIN ANALYZE and auto_explain shows all events for one query.  The
> > lock waits you are trying to record in the server log is one of the events.
>
> I am little bit sceptic about only memory based structure. Is it this
> concept acceptable for commiters?

Is this supposed to be session-local data, or is it visible from remote
sessions too?  How durable is it supposed to be?  Keep in mind that in
case of a crash, all pgstats data is erased.

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Álvaro Herrera                http://www.2ndQuadrant.com/
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