operate on it twice since the process pid slot assignment is immutable the bookkeeping process data structure created on the destination site includes the pm ui for the site that contains the process 39 pid and the actual pdf slot number that contains the process 39 pid thus the bookkeeping data structure can be employed to ascertain the pid for the migrated process for example the microkernel keeps track of the location in the multicomputer system of the process port ui for the migrated process pid thus the microkernel can be employed to direct messages to the migrated process based on the process 39 pid for example a globally atomic operation is of interest here the performance of globally atomic operations according to a present implementation of the invention shall be explained with reference to the illustrative drawings of fig9 a and 9b and fig1 an advantage of the process employed to implement a globally atomic operation in accordance with the present invention is that such is done securely the multicomputer system 400 of fig9 a and 9b are the same as those discussed above with reference to fig7 a however fig9 a and 9b illustrate exemplary relationships among the user application processes operative on sites 401 and 402 fig1 further illustrates the relationships among the various exemplary processes running on sites 401 and 402 specifically session number 1 includes.