[Simh] EXT :Re: some performance issues

[Mark Pizzolato]

On Wednesday, March 6, 2019 at 11:02 AM, gérard Calliet wrote:
> VAX hardware 89 VUPS
> 
> SIMH 27 VUPS
> 
> Gérard Calliet

I suspect you may be using some generally available DCL procedure to 
report the simulated system's VUPS.  That procedure may not map very 
well to the actual total system performance doing things other than 
somewhat tight loops in DCL on the system. A simulator in such a tight 
loop may easily have almost all of its activity hitting the host system's 
CPU cache while a more natural instruction mix (as in your Ada compiler 
activity) may be very different.

The simh version you are running (commit 8810571d) is 4 years and 
3 months old.

Maybe you should pick up the latest from https://github.com/simh/simh/archive/master.zip

Once you've got a recent version, you may want to try building both with
and without ASYNCH_IO.

The default IA64 builds with asynch I/O enabled.  You can build without 
asynch I/O with the following command:

    $ MMK/MACRO=(NOASYNCH=1) vax

Let us know what you find.

- Mark

> Le 06/03/2019 à 19:46, Hittner, David T [US] (MS) a écrit :
> > So from a performance analysis perspective, what are the VUPS ratings of
> > the VS4000-90 and the SIMH VAX running on the RX2800?
> > That's (more or less) the Integer performance rating.
> >
> > David