postmaster(s) have high load average

I have one process which writes a single float into 300 columns once per
second.  I then run 4 process, from remote computers, to query a small
subset of the latest row.

I have even commented out everything in the query programs, all they do
is sleep, and the associated postmaster still sucks up 15% - 20% CPU.

Computer is a P4 /w 1Gig memory, all disk access is local.  RH9 /w stock
postgresql-7.3 installed.

I have searched the documentation and tech site high and low for ideas....


  17:36:27  up 31 days,  6:07, 13 users,  load average: 4.11, 2.48, 1.62
107 processes: 99 sleeping, 8 running, 0 zombie, 0 stopped
CPU states:  22.3% user  76.0% system   0.0% nice   0.0% iowait   1.5% idle
Mem:  1030408k av,  976792k used,   53616k free,       0k shrd,  178704k
buff
                     715252k actv,   33360k in_d,   22348k in_c
Swap: 2048248k av,   91308k used, 1956940k free                  589572k
cached


   PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME CPU COMMAND
23389 cjw       16   0  2896 2752  2132 R    18.2  0.2   0:44   0 postmaster
23388 cjw       16   0  2896 2752  2132 S    18.0  0.2   0:45   0 postmaster
23391 cjw       16   0  2896 2752  2132 S    18.0  0.2   0:43   0 postmaster
23366 cjw       16   0  3788 3644  2560 S    17.8  0.3   2:32   0 postmaster
23392 cjw       16   0  2896 2752  2132 R    16.2  0.2   0:05   0 postmaster


--
--Chris

     How is it one careless match can start a forest fire, but it takes a
     whole box to start a campfire?