[Info-vax] VUPS.COM relevance for modern CPUs

[Mark Daniel]

Now, before everyone piles on, I understand the procedure provides an 
indicative/comparative/finger-in-the-air measurement of the relative 
performance of a VMS CPU relative to "the original VAX processor".

It states as much in the prologue:

|$! Provides an estimate of system CPU performance on OpenVMS systems.
|$! Use at your own risk.

To clarify the platform of a particular run I added:

|$ write sys$output f$fao("!AS with !UL CPU and !ULMB running VMS !AS",-
|f$edit(f$getsyi("hw_name"),"compress,trim"),-
|f$getsyi("availcpu_cnt"),-
|(f$getsyi("memsize")*(f$getsyi("page_size")/512)/2048),-
|f$edit(f$getsyi("version"),"collapse"))

which provides the likes of:

|HP rx2660 (1.40GHz/6.0MB) with 4 CPU and 14335MB running VMS V8.4-2L1
|Digital Personal WorkStation with 1 CPU and 1536MB running VMS V8.4-2L1
|innotek GmbH VirtualBox with 2 CPU and 7574MB running VMS V9.2

It seems to be implemented as a tight DCL loop that executes almost 
entirely in inner modes (I'm sure Brian can explain why).

$ start_cputime = f$getjpi(0,"CPUTIM")
$ loop_index = 0
$ 10$:
$ loop_index = loop_index + 1
$ if loop_index .ne. init_loop_maximum then goto 10$
$ end_cputime = f$getjpi(0,"CPUTIM")

|Combined for  2 CPUs         0         50        100       150      200
| Interrupt State             |                                       |
| MP Synchronization          |                                       |
| Kernel Mode              21 |▒▒▒▒                                   |
| Executive Mode           21 |▒▒▒▒                                   |
| Supervisor Mode          58 |▒▒▒▒▒▒▒▒▒▒▒                            |
| User Mode                   |                                       |
| Compatibility Mode          |                                       |
| Idle Time                99 |▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒                    |

100% (or all-but) of this execution appears to be in inner modes. 
Although X86 (above) seems to to have much more Kernel than other 
architectures, e.g. IA64 below).  There is no USER mode displayed in either.

|Combined for  4 CPUs         0         100       200       300      400
| Interrupt State           1 |                                       |
| MP Synchronization          |                                       |
| Kernel Mode               5 |                                       |
| Executive Mode           18 |▒                                      |
| Supervisor Mode          78 |▒▒▒▒▒▒▒                                |
| User Mode                   |                                       |
| Not Available               |                                       |
| Idle Time               299 |▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒          |

There appear to be (at least) two versions of these procedures.  The 
later contains:

|$! Modified: MAY-2010: Code updated by Volker Halle to address the
|$! following issues:

and tweaks a few of the calculations.

There also appear to be earlier tweaks allowing for Alpha processors

|$ cpu_multiplier = 10 ! VAX = 10 - Alpha/AXP = 40
|$ cpu_round_add = 1 ! VAX = 1 - Alpha/AXP = 9

but none for Itanium.

Are the Alpha tweaks sufficient to allow relevance for all 64bit CPUs?

Are further tweaks required to make measurements on Itania relevant?

And of course the same question for the successor to all three 
architectures?

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