[Info-vax] OpenVMS system programming language

Arne Vajhøj arne at vajhoej.dk
Sun Feb 23 21:09:53 EST 2025


On 2/23/2025 1:21 PM, Scott Dorsey wrote:
> Lawrence D'Oliveiro  <ldo at nz.invalid> wrote:
>> On Thu, 19 Dec 2024 15:56:43 +0900, David Meyer wrote:
>>> Have all the MACRO and BLISS programs been ported to C or C++, or will
>>> they be in the future?
>>
>> I hear there is this new language called “Java”, that is supposed to take
>> over from C++ ...
> 
> When Java first came out, I had this image in my head of a bunch of
> managers sitting around a table asking "What can we do to make computers
> more slow?  How can we sell people on more expensive hardware?"  "I know,
> we can get the UCSD P-System for the new millennium!"

Java 1.0.2 was probably rather similar to P-System regarding
hardware usage.

But if enough money is spent then problems get solved.

If we look at the traditional JVM problems:

byte code interpretation is slow - got fixed with JIT compilation
25 years ago, on VMS x86-64 the JVM JIT compiler is one of the
best optimizers

the JVM has many MB of memory as overhead - became irrelevant
when price of RAM dropped to a few dollars per GB

generational GC is very efficient at average but it has
horrible real time characteristics due to the dreaded
ms GC pauses - got fixed via special JVM's like Azul
Zing (with pauseless C4 GC) and in mainstream with the introduction
of ZGC that changed pauses from ms to us, we are still waiting
for ZGC on VMS though (we should get the non-generational
ZGC with Java 17 relative soon and the generational ZGC
with the next release 21 or 25)

huge upstart time due to JVM initialization and JIT
compilation - got fixed when AOT compilation was
introduced with Graal (Spring Boot Native, Quarkus
etc. all use Graal AOT), note that Graal is not available
on VMS and I have heard no indication that VSI is considering
porting it

None of this solved itself by magic. But Sun, IBM, Oracle etc.
put hundreds of thousands of man years into making it happen. So
it happened.

P-System had 2 problems: hardware was rather limited in its time
and nobody wanted to spend money on it like money was spent on JVM.

Arne




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