[Simh] Alpha simulator performance

[Sergey Oboguev]

> On Fri, Apr 20, 2012 at 09:01:11PM -0400, Dan Gahlinger wrote:

> Given that Cutler was the core architect on both, that isn't exactly 
>surprising. 
>

As a minor historical correction: whatever Cutler's merits are, he was not "the" 
core architect of VMS, as common legend has it.
As evidenced by the headers in VMS sources, he was just one of the key 
architects and developers for the kernel, let alone the whole system.
Even at early VAX architecture design state there were three key people on the 
software side (Hustvedt, Lippman and Cutler) and when it came down to the actual 
VMS design and implementation it naturally became even more diluted, with 
different people covering different major areas.

> Even though some of the later silly ideas (putting the entire GUI subsystem 
>into kernel mode to speed up graphics) were not his fault.

Silly -- from whose prospective?
Apparently not from the prospective of paying customers.

If GDI server goes down and everything else survives, from average customer's 
prospective the system is as good as dead (all GUI applications are killed and 
user session is destroyed, and that's what matters on a PC), and the next step 
is restart. So what would be the point of sacrificing performance (at the time 
when it still mattered) for virtually nothing?

As Torvalds once colorfully commented on a distinct but somewhat related issue: 
"message passing as the fundamental operation of the OS is just an exercise in 
computer science masturbation. It may feel good, but you don't actually get 
anything DONE. Nobody has ever shown that it made sense in the real world".

I might also mention that I had a coworker who previously spent 6 years at OSF 
working on virtual memory subsystem and similar stuff, and when I inquired him 
about his experiences, his very second comment was literally: "god, was it 
slow!".