[Simh] Workaround for idle

[bsupnik at comcast.net]

The idle detector in the VAX is declaring idle when it shouldn't.  In addition, device timeouts are causing idles when they shouldn't.

You can work around the problem, FOR VMS ONLY, by changing the parameters of the idle detector, as follows:

sim> d idle_ipl 8
sim> d idle_wait 1000

[On a really fast CPU, idle_wait may need to be higher.]

The idle detector was tripping on legitimate activity at IPL's 0 and 2, causing the system to go idle when it really wasn't.

In 3.7-2, the SET CPU IDLE command will take an OS parameter to specify how to tune the idle detector.

/Bob