meaning of "waiting" column in pg_stat_activity?
Just wondering...if a query is "waiting", what is it waiting for? Is
this only for locks, or can it be for disk, or a memory buffer? (If
there is a description of the meaning of things in pg_stat_activity
and it's relatives, I'd love a pointer, 'cause I can't seem to find
it.)
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On Mon, 2012-07-23 at 16:13 -0400, Chris Curvey wrote:
Just wondering...if a query is "waiting", what is it waiting for?
Locks.
Is
this only for locks, or can it be for disk, or a memory buffer?
Only locks.
(If
there is a description of the meaning of things in pg_stat_activity
and it's relatives, I'd love a pointer, 'cause I can't seem to find
it.)
There isn't much at the moment. 9.2 docs will be better in that regard.
See
http://www.postgresql.org/docs/9.2/static/monitoring-stats.html#PG-STAT-ACTIVITY-VIEW for example (but be careful that some columns of pg_stat_activity change in 9.2).
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