Re: ANALYZE locks pg_listener in EXCLUSIVE for long - Mailing list pgsql-hackers

From Philip Warner
Subject Re: ANALYZE locks pg_listener in EXCLUSIVE for long
Date
Msg-id 6.1.0.6.0.20040503135104.04ecabc0@203.8.195.10
Whole thread Raw
In response to Re: ANALYZE locks pg_listener in EXCLUSIVE for long time?  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: ANALYZE locks pg_listener in EXCLUSIVE for long time?  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
At 01:46 PM 3/05/2004, Tom Lane wrote:
>If it takes half an hour to ANALYZE pg_listener, I think that ANALYZE is
>not your real problem :-(.  You need a much more aggressive vacuuming
>policy on that table.  Maybe a cron job issuing "vacuum pg_listener"
>once a minute would do?  And get the size of the table knocked down to
>something less stratospheric to begin with --- perhaps stop all the
>listeners while you TRUNCATE the table.

It's a general ANALYZE command for the entire DB. It's about 6GB in size, 
and is vacuumed as frequently as possible; there is certainly unreclaimed 
space, but it does not substantially outweigh used space. My *guess* is 
that the largest table is being ANALYZEd at the time (it uses most of the 
6GB), and for some reason pg_listeners is being locked in ACCESS SHARE the 
entire time.

Just vacuuming pg_listener produces:

vacuum verbose pg_listener;
INFO:  vacuuming "pg_catalog.pg_listener"
INFO:  "pg_listener": found 0 removable, 0 nonremovable row versions in 0 pages
VACUUM


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