Hi Christian, thanks for the review!

p 4, l 26: old typo? "indentifier" -> "identifier" fixed

p 49, l 36: question for "the communication may progress independently of the computations at all participating processes": What about all the Reduce operations which involve both communication and computation? Should we replace "the communication may progress" with the more general "the operation may progress"? changed

p 50, l 14: same argument as above; replace "collective communication" with "collective operation" changed

p 50, l 31: "using normal point-to-point" is not accurate/sufficient enough => "using nonblocking point-to-point" ah, that's minor - changed anyway

p 65, 5.13: The example is good but the current text is bad. It is simply not allowed to call NBC in a different order. If a certain implementation runs into a deadlock does not matter. This would even be on of the better scenarios (i.e. an easy-to-noticeable error). Other implementations could complete both bcasts (because it thinks they match) but provide the wrong data (i.e. the data from the other bcast or even a mixture?) - which is a much harder failure to detect. which example are you referring to? Only Ex 5.24 is on this page and doesn't use NBC (and the phrasing "deadlock" is used correctly there.

p 66, example 5.25: should we add sth like the following at the end? "Note: Using nonblocking collectives can fix such problems, see example 5.34." added

p 69, l 32: maybe better "However, communicator construction might induce overheads and consume resources so that this should be used economically." not changed (decided on telecon)

p 70, example 5.31: To me this example is not "per se" illegal. Both operations simply don't match - that's fine. However, it is possible to extent the example so that the final program is still a valid MPI program. Maybe just add sth. like "in this form" or "without additional collectives that match". no, it's not possible to make this correct if both ranks call it at the same time. Remember, blocking and nonblocking colls have the same matching "namespace".

All the Best, Torsten -- bash$ :(){ :|:&};: --------------------- http://www.unixer.de/ ----- Torsten Hoefler | Postdoctoral Researcher Open Systems Lab | Indiana University 150 S. Woodlawn Ave. | Bloomington, IN, 474045, USA Lindley Hall Room 135 | +01 (812) 855-3608