Patent ID: 7529855

Claim:
A method of dynamically modifying a fragmentation size cluster communication parameter in a clustered computer system, the method comprising: deferring processing of a requested fragmentation size change until receipt of an acknowledgment message for at least one unacknowledged message sent by a source node to a plurality of target nodes prior to the requested fragmentation size change, wherein the acknowledgment message is sent in response to a sync message sent from the source node to the plurality of target nodes in response to the requested fragmentation size change, and wherein the acknowledgement message acknowledges receipt for at least one unacknowledged message other than the sync message; thereafter processing the requested fragmentation size change to modify a fragmentation size cluster communication parameter that controls a maximum packet size used when fragmenting messages transmitted from the source node to the plurality of target nodes; and thereafter sending messages from the source node to the plurality of target nodes using the modified fragmentation size cluster communication parameter.