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From: montra@ghost.unimi.it (Paolo Montrasio)
Newsgroups: comp.os.research
Subject: Re: lightweight process
Message-ID: <16082@darkstar.ucsc.edu>
Date: 20 May 91 13:05:17 GMT
Article-I.D.: darkstar.16082
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Organization: Computer Science Dep. - Milan University
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yunyau@bingvaxu.cc.binghamton.edu (Yun Yau Shih) writes:

>Hi there:

>A few days ago, I post a question to comp.os.misc but received one
>reply only. So, I post to this group and hope I can get much more
>comment/reference. 

>My question is :

>Could anyone give me a simple *example* for lightweight process?
>I know the definition and try to catch a much more concrete idea.

>Any comment is appreciated.

I never used them, but I _think_ they are something a UNIX fork() that
doesn't duplicate the process memory image. The lightweight processes
share the same code, so they are not as indipendent as normal (heavyweight)
processes are. The contest-switch time is greatly reduced because the OS
needs only to save the registers.

Lightweight processes are sometime referred (in implementatios)
as "threads". I know that the Mach O.S. (the kernel of Next BSD O.S.) has
threads.

I hope somebody will be able to help you more than I did, however this is
all I know about this topic.
                             _____
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.--------------------------|\ P M /|---------------------------------------.
|                          |_\   /.|   |        Paolo Montrasio            |
| Don't study, don't work, |--\_/--|   |        montra@ghost.unimi.it      |
|      play the Core War!   \ \_/ /    |        montra@[131.175.10.64]     |
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