[Info-vax] clock problems with OpenVMS x86 on VirtualBox

[David Turner]

Like I have always suspected.
I think there is more of an emulator in the OpenVMS x86 code than has 
been admitted.
The faster the CPU on the virtualbox the faster your "native X86" code 
is gonna run
Anyone care to elaborate or prove this?


DT


On 5/6/2023 12:49 PM, Craig A. Berry wrote:
>
> I am running OpenVMS x86_64 E9.2-1 under VirtualBox 7.0.8 on macOS
> Ventura 13.3.1 (a).  The host is a 2019 MacBook Pro with 2.3 GHz 8-Core
> Intel Core i9.  The clock isn't working right, most easily seen by the
> fact that the following two commands were typed exactly one minute apart:
>
> $ sh time
>    5-MAY-2023 19:07:35
> $ sh time
>    5-MAY-2023 19:07:45
>
> So the system advances its clock about 10 seconds for every 60 seconds
> of actual time.
>
> Another way of illustrating the problem is by running the vups.com from
> <https://emuvm.com/download/vups-com-benchmark/>, which says:
>
>  Approximate System VUPs Rating : 10430.2 ( min: 950.4 max: 55125.0 )
>
> Divide that number by 6 and it might almost be credible based on numbers
> other people have been posting, though a factor of 10-15 would be more
> believable.  The system is *not* in fact fast at all -- it takes about
> 15 seconds for MONITOR SYSTEM to initiate its display when nothing at
> all is running.
>
> I have not seen this anywhere in the VSI documentation, but this blog 
> post:
>
> <https://raymii.org/s/blog/OpenVMS_9.2_for_x86_Getting_Started.html>
>
> says it's necessary to set the clock characteristics of the virtual
> machine like so:
>
> $ vboxmanage modifyvm <vmname> --hpet on
>
> I have done so but observe no difference (everything posted above was
> after running this command and restarting VirtualBox).  Supposedly this
> setting "Enables . . . a High Precision Event Timer (HPET) which can
> replace the legacy system timers," whatever that means. I guess one
> possibility is that the command, while it returned no errors, also
> didn't take effect for some reason.  I cannot tell from the following
> output whether the non-default setting is in effect:
>
> $ vboxmanage debugvm <vmname> info hpet
> HPET status:
>  config=0000000000000003     isr=0000000000000000
>  offset=fffffff020435102 counter=0000000000000000 frequency=69841279 fs
>  legacy-mode=on   timer-count=4
> Timers:
>  0: comparator=0000001022973a28 accumulator=0000000000022f4d (9999944 ns)
>         config=ffffffff0000003c irq=0 en per cap_per cap_64
>  1: comparator=00000000ffffffff accumulator=0000000000000000 (0 ns)
>         config=ffffffff00000000 irq=8
>  2: comparator=00000000ffffffff accumulator=0000000000000000 (0 ns)
>         config=ffffffff00000000 irq=0
>  3: comparator=00000000ffffffff accumulator=0000000000000000 (0 ns)
>         config=ffffffff00000000 irq=0
>
>
> Has anyone sen anything like this or has any ideas on how to debug/fix
> it?  The only next step I can think of is to try VMWare Player and see
> if it works better than VirtualBox.
>