Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!taumet!steve
From: steve@taumet.com (Stephen Clamage)
Newsgroups: comp.lang.c++
Subject: Re: The Scheduler in the Task.h class consumes CPU when idle.
Keywords: tasks task.h cpu
Message-ID: <518@taumet.com>
Date: 18 Nov 90 00:34:28 GMT
References: <1990Nov7.034557.7605@clear.com>
Organization: Taumetric Corporation, San Diego
Lines: 24

rmartin@worf.clear.com (Bob Martin) writes:

|I have been experimenting with the "task.h" classes in the Sun
|distribution of C++ 2.0.  I have been able to create tasks which
|are happy to share the CPU as true coroutines.  I have also been
|able to use the Interrupt class to catch timer signals in order to
|implement timed delays for tasks.  However, when all tasks are 
|blocked, waiting for an interrupt, the scheduler seems to hang
|in an infinite loop consuming as much of the CPU as it can.  

|Does anybody out there know how to fix this problem.  I would like
|to use the task class, but cannot afford to have a process eat all
|the available cpu.

The implementation of the AT&T tasking library from Oregon Software sleeps
while waiting for interrupts, rather than busy-waiting.  You might want to
try it.  It does require the Oregon compiler, as it assumes Oregon-specific
code generation.  The tasking library is presently available for the Sun 3
series.

Disclaimer:  I wrote the implementation.
-- 

Steve Clamage, TauMetric Corp, steve@taumet.com