I walked in this morning and looked at the load on our master db and  
saw that between 4:30-6PM last night the average load went steadily up  
from 0.5 to 2.5.  Using top I see that the two FETCH queries from Slony  
are swallowing two of our four CPUs:

   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
19029 postgres  16   0  671m 600m 668m R 73.0  7.9 788:58.38 postgres:  
postgres tii 192.168.1.42 FETCH
19206 postgres  16   0  671m 600m 668m R 72.7  7.9 788:46.65 postgres:  
postgres tii 192.168.1.43 FETCH

The %CPU vacillates  between 70-90%.

A further inspection of the stat activity confirms this:

tii=# select procpid, query_start, age(now(),query_start),  
current_query from pg_stat_activity where current_query not like  
'%IDLE%' order by query_start;
  procpid |          query_start          |       age       |     
current_query
---------+-------------------------------+----------------- 
+----------------------
    19029 | 2005-03-04 09:29:44.71891-08  | 00:00:06.708432 | fetch 100  
from LOG;
    19206 | 2005-03-04 09:29:47.768228-08 | 00:00:03.659114 | fetch 100  
from LOG;

The age ranges anywhere from 0 to 9 seconds.

The load on the two slaves hasn't changed.

BTW There are no idle in transactions over 5 seconds old.  We saw  
similar behavior before due to some poorly configured clients causing  
long
transactions.

Any help or thoughts would be greatly appreciated!

Cheers,

Christian

Christian Storm, Ph.D.
CTO iParadigms, LLC