mysterious log output

I keep seeing the following log output around every 5 minutes:

2005-02-28 23:25:05 [8646] LOG:  00000: QUERY STATISTICS
DETAIL:  ! system usage stats:       !       0.005023 elapsed 0.000000 user 0.000000 system sec       !
[537.130000user 44.860000 sys total]       !       0/0 [0/0] filesystem blocks in/out       !       0/4
[848810/1849693]page faults/reclaims, 0 [0] swaps       !       0 [0] signals rcvd, 0/0 [0/0] messages rcvd/sent
!      0/0 [0/0] voluntary/involuntary context switches       ! buffer usage stats:       !       Shared blocks:
 0 read,          0 written, buffer hit 
 
rate = 100.00%       !       Local  blocks:          0 read,          0 written, buffer hit 
rate = 0.00%       !       Direct blocks:          0 read,          0 written
LOCATION:  ShowUsage, postgres.c:3199


The server is postgresql 7.4, running on debian linux.  According to 
postgres.c, it should be outputting due to GUC, however I verified that all 
of the log_*_stats lines in the postgresql.conf are turned off and also 
verified those GUC's are off in the show all; output... here's the relevant 
bits.    

log_connections                | offlog_duration                   | offlog_error_verbosity            |
verboselog_executor_stats            | offlog_hostname                   | offlog_min_duration_statement     |
5000log_min_error_statement       | infolog_min_messages               | noticelog_parser_stats               |
offlog_pid                       | onlog_planner_stats              | offlog_source_port                |
offlog_statement                 | offlog_statement_stats            | offlog_timestamp                  | on
 

the only thing real sketchy about this is that it always seems to be on the 
same pid (8646) and if I turn query logging on I see the following executed 
right before this happens:

2005-03-01 00:25:08 [8646] LOG:  00000: statement: select 
"_rv".cleanupEvent();
LOCATION:  pg_parse_query, postgres.c:464

now according to the slony folks, there is nothing in slony that modifys the 
logging output... so assuming that's true, anyone have any ideas on what 
might be causing this logging? 

-- 
Robert Treat
Build A Brighter Lamp :: Linux Apache {middleware} PostgreSQL