Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!att!chinet!les
From: les@chinet.chi.il.us (Leslie Mikesell)
Newsgroups: comp.unix.wizards
Subject: Re: What kinds of things would you want in the GNU OS?
Message-ID: <8591@chinet.chi.il.us>
Date: 31 May 89 05:01:23 GMT
References: <106326@sun.Eng.Sun.COM> <31756@bu-cs.BU.EDU> <8565@chinet.chi.il.us> <10336@smoke.BRL.MIL>
Reply-To: les@chinet.chi.il.us (Leslie Mikesell)
Organization: Chinet - Public Access Unix
Lines: 15

In article <10336@smoke.BRL.MIL> gwyn@brl.arpa (Doug Gwyn) writes:

>The supposed advantage of a thread is that it's cheap to create one,
>even compared with setting up copy-on-write for a fast fork().  The
>obvious disadvantage is that the shared data space requires use of
>concurrency controls among the parallel threads (e.g. monitors).

That's what I thought, but I can't see where it would be useful, except
perhaps to make up for certain OS functions that might be lacking
like the ability to cheaply determine that no I/O is pending on any
of several channels so you can continue doing some work without needing
a new thread.  Wouldn't there be a problem with static data in
library routines (or anywhere else)?

Les Mikesell