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Screen dimming can cause infinite loops

When we need to give demos on our Symbolics, we occasionally do them in
a conference room which requires us to disconnect the console from its CPU,
move the console and reconnect it.  When we do multiple demos and use multiple
monitors, it is not unusual for us to have several machines disconnected from
their screens waiting their turn to get the daisy-chained monitors.
(All the machines I am talking about have IO6, FEP 127)

We have learned by sad experience (very sad when it is a demo), that a machine
may encounter problems in such a state.  The symptom is that some process goes
into a run state and chews up all of memory.  It appears that the Screen
Blanking process (on the timer queue, usually) is at fault.  

I haven't had enough chance to track this down but I wanted to check to see if
you have a patch for it.

By the way, the best we can do now is to (SI:HALT) the machine in the FEP before
disconnecting it from its monitor and CONTINUE it when it is reconnected.  That
works ok unless someone else needs files off its disk.  (Right now we have
4 separate machines waiting for their turn to give demos (on 4 monitors).  One
of those is the SYS host!)  This workaround is not sufficient.

And if we do get into this state, the best thing to do is do Function-Control-A
and then go into the peek window (Function-A to unarrest it) and then unarrest
the processes that you want to.