Master-worker-pattern

The Master-worker-pattern correspondents to the typical master-worker-scheme: a master dispatches pieces of work to several workers. Each worker does his piece of work. When finished he sends his result to the master and requests for a new piece of work (and so on). When all work is done, the master sends an stop-signal to the workers.
This scheme is important in practise, since it automatically balances load. In pseudo-code the Master-worker-scheme looks like:

Every abstract communication ``code'' in the scheme above can be filled with concrete MPI_Code. We measure the time consumed by dispatch work. This code sequence does for example this: