autovacuum daemon stops doing work after about an hour

I took advantage of last weekend to upgrade from 7.2.4 to 7.4.0 on a
new faster box.

Now I'm trying to implement pg_autovacuum.  It seems to work ok, but
after about an hour or so, it does nothing.  The process still is
running, but nothing is sent to the log file.

I'm running the daemon as distributed with PG 7.4 release as follows:

pg_autovacuum -d4 -V 0.15 -A 1 -U postgres -L /var/tmp/autovacuum.log -D

the last few lines of the log are:

[2003-12-02 11:43:58 AM] VACUUM ANALYZE "public"."msg_recipients"
[2003-12-02 12:24:33 PM] select relfilenode,reltuples,relpages from pg_class where relfilenode=18588239
[2003-12-02 12:24:33 PM]   table name:     vkmlm."public"."msg_recipients"
[2003-12-02 12:24:33 PM]      relfilenode: 18588239;   relisshared: 0
[2003-12-02 12:24:33 PM]      reltuples: 9;  relpages: 529132
[2003-12-02 12:24:33 PM]      curr_analyze_count:  1961488; cur_delete_count:   1005040
[2003-12-02 12:24:33 PM]      ins_at_last_analyze: 1961488; del_at_last_vacuum: 1005040
[2003-12-02 12:24:33 PM]      insert_threshold:    509; delete_threshold    1001
[2003-12-02 12:24:33 PM] Performing: VACUUM ANALYZE "public"."user_list"
[2003-12-02 12:24:33 PM] VACUUM ANALYZE "public"."user_list"
[2003-12-02 12:43:19 PM] select relfilenode,reltuples,relpages from pg_class where relfilenode=18588202
[2003-12-02 12:43:19 PM]   table name:     vkmlm."public"."user_list"
[2003-12-02 12:43:19 PM]      relfilenode: 18588202;   relisshared: 0
[2003-12-02 12:43:19 PM]      reltuples: 9;  relpages: 391988
[2003-12-02 12:43:19 PM]      curr_analyze_count:  1159843; cur_delete_count:   1118540
[2003-12-02 12:43:19 PM]      ins_at_last_analyze: 1159843; del_at_last_vacuum: 1118540
[2003-12-02 12:43:19 PM]      insert_threshold:    509; delete_threshold    1001

Then it just sits there.  I started it at 11:35am, and it is now
3:30pm.

I did the same last night at about 10:58pm, and it ran and did work until
11:57pm, then sat there until I killed/restarted pg_autovacuum this
morning at 11:35.  The process is not using any CPU time.

I just killed/restarted it and it found work to do on my busy tables
which I'd expect.

I'm running Postgres 7.4 release on FreeBSD 4.9-RELEASE.

--
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Vivek Khera, Ph.D.                Khera Communications, Inc.
Internet: khera@kciLink.com       Rockville, MD       +1-240-453-8497
AIM: vivekkhera Y!: vivek_khera   http://www.khera.org/~vivek/