Newsgroups: comp.parallel.pvm
From: dan@graphics.cornell.edu (Daniel Kartch)
Subject: Mixed send and mcast don't preserve order !?!?
Organization: Program of Computer Graphics -- Cornell University
Date: 10 Aug 1994 20:27:23 GMT
Message-ID: <32bd7b$g7p@merckx.graphics.cornell.edu>

I've just encountered what I think might be a bug in PVM.
I'm running version 3.3.3 on a cluster of HP workstations.

The problem is that when one of my processes sends a message to several
processes with pvm_mcast, and then immediately calls pvm_send to send a
message to one of those processes, the pvm_send message sometimes arrives first.
The problem only seems to occur when I use the PvmRouteDirect option.

I'm not sure this is a bug because the user's guide only talks about guaranteed
message ordering in the man page for pvm_send.  It doesn't say anything
about ordering of mcast messages or mixed send/mcasts (or at least my
quick search didn't find any mention of it), but my intuitive reaction is
that it should guarantee ordering in those cases as well.  Can anyone tell
me if this is known problem or should I report it?


-- 
+-----------------------------------------------------------------------------+
|      Daniel Kartch                             582 Theory Center Bldg.      |
|      Program of Computer Graphics              Cornell University           |
|      Cornell University                        Ithaca, NY 14853             |
|      dan@graphics.cornell.edu                  (607) 255-6704               |
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