Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!samsung!think!ames!vsi1!daver!tscs!usfvax2!ziggy!hall
From: hall@ziggy.EDU (Lawrence O. Hall)
Newsgroups: comp.os.mach
Subject: Mach timers on a Multimax
Message-ID: <1303@ziggy.EDU>
Date: 29 Dec 89 18:33:43 GMT
Reply-To: hall@ziggy.cmd.usf.edu.UUCP (Lawrence O. Hall)
Organization: University of South Florida, Tampa, FL
Lines: 27

We have a couple of questions about Mach, which are probably very 
basic, but here goes...

1)  While using C is there another timer available under Mach which 
provides microsecond or millisecond accuracy on the Encore Multimax, 
besides "gettimeofday"?

2) In our use of gettimeofday it seems that calls to it get
put into a priority queue of some type and are not necessarily processed
in the order made.  We see threads which do the same exact thing take
radically different run time intervals under gettimeofday.  
Is it possible the calls are queued in some fashion? 

3)  Again trying to obtain  the time interval of each thread and a parent
processor doing  the same task, we find that the parent appears to be
interrupted (or something) and it takes longer to accomplish the task than
do its children.  Is this possible?  Should the parent not do concurrent
work?

We would very much appreciate answers or pointers to the answers of these
questions.  Thank you in advance for any help.

--Larry Hall
hall@sol.usf.edu
Dept. of Computer Science and Engineering
University of South Florida
Tampa, Fl. 33620