[nos-bbs] multitasking jnos

[Maiko Langelaar (ve4klm)]

Skip,

> This is a new thread - interesting perhaps only to myself?

No, it's of interest to me too, BUT, it's not that easy a topic.

Based on the limited reading that I've done so far, user space threads
may actually be a more efficient way to deal with multitasking, rather
then try and use the kernel threads. As a matter of fact, there is some
reading that suggests the PTH (portable threads library) is the same. Of
course any NOS is more or less it's own PTH. The beauty of implementing
user space threads in JNOS for instance also has the added advantage of
not having to worry about locking resources, since technically only one
thread (NOS process) can work on a resource at a time. Portability is
much easier with user space threads. Sorry, back to your question ...

Honestly, I have yet to get really deep into the performance issues around
the context switching calls. It has never been a real issue for me. Quite
frankly, it still is not a big issue for me. BUT - at the same time, it's
probably something I should pay more attention too.

For those interested, here's a very technical, possibly interesting site,
that discusses threads, kernel and user-space. I do read these types of
articles from time to time to try and get better understandings of the
issues. Anyways, here's the link, hope you all find it interesting :

    http://evanjones.ca/software/threading.html

> Does jnos contain a task scheduling algorithm that is suitable for DOS
> but may be redundant with linux task scheduling ? Then if jnos does
> contain a task scheduler, is there a way to permit higher CPU
> utilization on a Linux platform ?

I can't answer that. If I am to do so, I need to *study* it alot more.

Maiko Langelaar / VE4KLM