aborted2 3 reserved______________________________________ for completion status values 0 and 1 the space for the message was allocated in the message reception area and the memory must be freed length 1 field bits 10 26 specifies the length of the allocated memory in memory lines 32 byte increments for the message a zero value specifies one memory line 32 bytes and a value of all ones specifies 131 072 memory lines 4 mbytes start offset field bits 40 58 specifies the offset in to the memory reception area to the start of the message fig1 and 13 describe the memory structures used by the messaging and data copy hardware the three data structures are the message reception area is an operating system allocated region of memory to which messages can be written the message reception area is controlled by hardware that allocates message space and writes the messages as they are received all accesses to message reception areas are through coherent memory accesses a processor can copy a message out of the message reception area directly or by using the data copy hardware the message completion queue area holds message completion status until software is ready to process the received message in the hewlett packard excalibur product used as an example of enablement of the present invention the size of each message completion queue area is fixed at 16 kbytes each entry is 8 bytes in size resulting in 2048 entries per queue the message completion queue area resides in memory.