[Simh] SIMH vax.ini fine tuning

[Peter Svensson]

On Mon, 19 Sep 2011, Seth Morabito wrote:

> * On Mon, Sep 19, 2011 at 10:20:48PM +0200, Arpadffy Zoltan <Zoltan.Arpadffy at scientificgames.se> wrote:
> > I am so happy that thanks to Mark's master build I finally have a
> > stable system used through the network.
> >
> > ...but there are still some fine tuning issues that, unfortunately
> >  could not find any reference in the manuals.
> > 
> > 1. what is the proper method enabling of the sim_idle_enab flag? I
> >  have tested the "set cpu idle" command but the CPU is still in 100%
> >  usage
> 
> With the stock 3.8-1 release, you'll need TWO lines (both of these are
> required!):
> 
>   set cpu idle
>   set cpu idle=ultrix
> 
> There seems to be a bug that causes the simulator to say "Invalid
> argument" after the second line, but the idle flag is correctly set
> anyway. Do a "show cpu" at the "sim>" prompt and you should see
> something like:
> 
>   sim> show cpu
>   CPU, idle enabled=ULTRIX, 64MB, HALT to SIMH

You need the vax-idle patch from 
  http://sourceforge.net/projects/simh/files/Unofficial%20Patches/3.8.1/
for idle to work properly for all the supported operating systems. With 
this patch I can run a VMS-cluster of several VAXen on the same host with 
good performance.

Also very _very_ nice is the tuntap patch for native tap support. No more 
taptap hacks. Very much more straight forward to set up networking using 
bridging on hosts that support tun/tap virtual interfaces (Linux, *BSD 
etc).

Peter