Re: New version of the chapter

Eric Salo (salo@mrjones.engr.sgi.com)
Mon, 14 Oct 1996 12:46:04 -0700

> 1. Use of groups as arguments in post and start. We argued that it is
> easier to cache a group than a list. There is another performance
> penalty that we did not discuss: the cost of checking that each process
> in the argument group is also a process in the window group. When the
> input argument is a list of ranks, the test is simply an "in range" test
> for each rank. With a group member list, the test becomes more
> expensive.

I don't see this as a problem. Specifying an illegal group is erroneous and so
we're free to not perform this check if it's too expensive.

-- 
Eric Salo         Silicon Graphics Inc.             "Do you know what the
(415)933-2998     2011 N. Shoreline Blvd, 8U-802     last Xon said, just
salo@sgi.com      Mountain View, CA   94043-1389     before he died?"