Broadcast Shared Memory (BSM): Introduction


BSM is an update-based protocol that takes special advantage of the unique Memory Channel network. The protocol uses the remote-write capabilities of the network to deliver updates and also uses the network special software interface to efficiently access the network.

An extra pass is added to the compilation process. This pass processes the assembly language files and doubles all store operations. The first store sends data to local memory, as normal. The second store then sends data to network interface (using memory-mapped IO space), which then forwards the data to the appropriate destination.


BSM: Command Line Arguments

BSM claims all command line argument following a ``--''. Arguments before the ``--'' should be processed by the user application.

For example, to start the application ``ufft'', you could give the following command line:

ufft -n 512 -- -p:5

``Ufft'' would process the command line arguments -n 512. BSM would precess the command line argument -p:5.


BSM supports the following command line arguments:
-c:cpus
Sets the maximum number of compute processes (CPUs) that will be started on each node. If no -c: argument is given, all available processors will be used for either compute processes or protocol processes.
-n:nodes
Sets the maximum number of nodes that will be used to run the application. If no -n: argument is given, all nodes in the cluster will be used.
-p:processes
Sets the maximum number of compute processes that will be used to run the application. If no -p: argument is given, all available processors will be used subject to the limitations implied by any -c: or -p: arguments.

-i
Use inter-node interrupts for message notification.

-d:debug_level
Sets the level of debugging information printed by the protocol library. The default is level 0, meaning no debugging information.

Note that numeric values for command line arguments may be given either in decimal or hexadecimal. If hexadecimal is used, the value must be prefixed with a ``0x''.