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From: BGB <cr88192@gmail.com>
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Subject: Re: My 66000 and High word facility
Date: Mon, 19 Aug 2024 12:07:59 -0500
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On 8/19/2024 11:05 AM, Stefan Monnier wrote:
>> Task swapping time is way down in the noise. It’s reloading the L1 and L2
>> cache that swamps the time. 64 registers is nothing compared to 32k or
>> megabytes.
> 
> Depends on the kind of swap.  If you're thinking of time-sharing
> preemption, then indeed context switch time is not important.
> 
> But when considering communication between processes, then very fast
> context switch times allow for finer grain divisions, like
> micro-kernels.
> 
> Historically, these things have never really materialized, admittedly.
> 

FWIW: One of the things that led me to the temptation to consider 
register banks, was not "ye olde preemptive task scheduling", but rather 
the relatively higher cost of performing COM-like method calls between 
one task and another.

Theoretically, with 4 banks:
   Task 1, Task 2, Kernel / Syscall, Interrupt
The caller could be put in Task 1 and the called task in Task 2.

....


> 
>          Stefan