[Info-vax] OpenVMS.Org quick pool

[David Froble]

Bob Koehler wrote:
> In article <k0lo3u$guc$1 at usenet01.boi.hp.com>, Keith Parris <keithparris_deletethis at yahoo.com> writes:
> 
>> No changes would 
>> be required in OpenVMS I64 code for it to run inside such an environment.
> 
>    And no performance would be achieved.  x86 isn't yet fast enough and
>    IA64 isn't slow enough for x86 to emulate IA64 at near IA64 hardware
>    speeds.

It's not just the CPUs and performance.  It's about device support and such.  As 
an example, my VAXs and some of the Alphas use 50 pin SCSI disks.  The last one 
of those I saw was in the clutches of a Dodo bird.

So an important issue is hardware support for available hardware.  For VAX, that 
would include PCI support in the OS, and HW implementing PCI, and S-ATA, and ... 
  Today.  Tomorrow, who knows.

That is one feature of the emulators, as long as they can run on current 
hardware, you're not faced with possible extinction every moment.

>    Like emulating VAXen on modern chips, it could get there, some day.
>    But if someone had decided to keep making VAXen, I suspect they'd
>    be using modern processes and clock speeds, and VAX emulators wouldn't
>    be running on chips with so much advantage that the emulation beats
>    hardware speed.

You bet.  It's an interesting question how fast an N-VAX or descendant processor 
would run at 35 nm.

>    In the intervening years, Alpha was one hot chip, and IA64 wasn't
>    bad.  Where would IA64 customers go in the meantime for VMS at
>    competitive performance?
>