Gluster users - Jan 2012 - top results show "No entries in list" for some bricks

Hello All-

I have been experimenting with the "gluster volume top" commands in
the
search for performance bottlenecks.  For some bricks fewer than list-cnt 
files are listed for read and write speed tests, and for some bricks no 
filenames are listed at all even though throughput figures are reported 
for all the bricks.  See below for example, which shows read-perf 
results from two bricks on the same server.

Brick: bdan13.nerc-essc.ac.uk:/nemo/glusterfs
Throughput 51.20 MBps time 0.0000 secs
No entries in list
Brick: bdan13.nerc-essc.ac.uk:/nemo8/glusterfs
Throughput 128.00 MBps time 0.0000 secs
MBps Filename                                        Time
==== ========                                        ===    0
...ice_assm/1989/ORCA025-FOAM_y1989m12_gridT.nc 2012-01-04
11:44:12.71083
    0 ...ice_assm/1989/ORCA025-FOAM_y1989m05_gridT.nc 2012-01-04 
11:44:09.250759

This happens whatever the value of list-cnt.  Does this indicate a 
problem with those bricks, or is there a bug in the gluster "top"
feature?

-Dan.