On Feb 25, 2010, at 3:56 AM, Amr Hassan wrote: > Thanks alot for your reply, > > I'm using blocking Send and Receive. All the clients are sending data and the > server is receive the messages from the clients with MPI_ANY_SOURCE as the > sender. Do you think there is a race condition near this pattern?
MPI_ANY_SOURCE can definitely lead to race conditions / messages (and content) from unexpected sources. Try using explicit sources, if possible. > I searched a lot and used totalview but I couldn't detect such case. I really > appreciate if you send me a link or give an example of a possible race > condition in that scenario . You might want to let it run to segv in TV and see exactly where the segv occurs in your code. Is your code processing what it thinks is message A but is really message B? If the content (and therefore the processing of) B is different than A, then assumptions can go badly in your code and Bad Things may happen. > Also, when I partition the message into smaller parts (send in sequence - all > the other clients wait until the send finish) it works fine. is that exclude > the race condition? No. It somewhat suggests that you do have a race condition. -- Jeff Squyres jsquy...@cisco.com For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/