[Info-vax] VMS port to x86

[Paul Sture]

On Tue, 27 Mar 2012 10:41:59 -0600, Keith Parris wrote:

> On 3/24/2012 11:40 PM, JF Mezei wrote:
>> SimH causes one core of an x86 to run at 100% all the time to emulate
>> the vax.  A Mac Pro computer running at 100% consumes about as much
>> power as a DS10L.
>>
>> If SimH could "capture" the idle loop and sleep the process instead,
>> then power consumption might be down, but not that much.
> 
> SimH can detect the idle loop and throttle back. Hoff has a great
> write-up on this at http://labs.hoffmanlabs.com/node/931

I have just added a comment to that topic:

http://labs.hoffmanlabs.com/node/931#comment-2766

My findings so far indicate that VAX/VMS will only use 12-14% of a twin 
cpu Pentium 4 when running under SIMH and Linux and the full complement 
of Hobbyist software (OK, when just sitting at the DCL prompt).

It's a far cry from when I was using prior versions of SIMH on an iBook 
or PowerBook and hearing the fans rev up due to 95+ percent CPU usage :-)


-- 
Paul Sture