The present invention provides a system and method for modifying an information unit, the method includes the following stages: (i) receiving, over a first bus, a request to initiate a snooping type atomic operation associated with at least one information unit located at a first address of a memory module; (ii) providing the information unit over the first bus; (iii) attempting to complete the snooping type atomic operation of an updated information unit; and (iv) defining the atomic operation as a failed atomic operation if during at least one stage of receiving, providing and attempting, the first address was locked as a result of a locking type atomic operation.