[Info-vax] KP threads

[David Jones]

On Thursday, December 23, 2021 at 3:14:42 PM UTC-5, John Dallman wrote:
> I agree. The KP_ routines seem, looking at the explanation in Appendix C 
> of "Porting Applications from Alpha to IA64," to have been created to let 
> applications' internal coroutine systems work on IA-64. The hardware 
> stack implementation on that architecture is a lot more complicated than 
> VAX, or Alpha, or x86-64. It's fairly transparent if you use the stack 
> simplistically, but it isn't really designed for DIY coroutines, or other 
> clever trickery. 
> 

The origin of the Kernel Process Services goes back to 1990. That VEST-specific
areas are part of the parameter block leads me to think that was the original
motivation, plus the growing intricacies of things like the SCSI class driver.