We have a system running QNX 6.5.0 as a TCP/IP server processing proprietary data.  The service threads run with round-
robin scheduling.  Under very heavy loading, we can get one thread blocking in a recv call on its socket.  When this 
happens, the other service threads run, but the blocked thread prevents any lower-priority threads from running. When 
this happens, we stop all requests and let the machine catch up.  The blocked thread remains in this state.  

I would have thought that a blocked recv call would suspend, letting lower-priority threads still run.  I'm still 
gathering information on the state of the machine and can post more details later, but I would like to know if it is 
normal or know condition that a blocked recv call can prevent lower-priority threads from running?