ypserv cpu-loop with group.bygid?

[Jim Davis]

I'm trying to chase down an intermittant problem with ypserv, running on 
a FreeBSD 4.8 p-14 system, configured as a slave server.  Periodically 
the ypserv process starts burning huge amounts of CPU -- top will show 
it at 70%-80% of the system, where normally the usage is well under 
10%.  In those situations interactive response goes down the drain.  
That slave server is set up so that it binds to itself as a yp client.

Running truss on the ypserv process shows it in a tight loop reading the 
group.bygid map.  I've dumped the group.bygid map contents to a file and 
run chkgrp(8) on it, thinking perhaps there was some bogus data in the 
source file or other formatting problem -- but chkgrp doesn't find any 
errors.  There are no error messages being logged while ypserv is 
buzzing; it's just very, very busy.

Any ideas on what to check?  Normal yp operation seems to be okay; the 
problem happens rather infrequently, though it's a showstopper when it 
does happen.