Fault tolerant and load sharing processing system

摘要

Incoming data messages to a system having a plurality of channels are assigned for processing to one of the channels to share the processing load more or less equally among all the channels of the system. Each channel receives messages by means of a communications link for processing. Included in each channel is a disk drive for a storage medium, a disk controller and peripheral controllers for input/output equipment as required. Each channel of the system also includes a data processor. A message is received from the communication link of any of the channels, which message is identified by the data processor of that channel. The processor then evaluates the number of messages waiting to be processed in each of the other channels for assignment to a channel having the least number of messages on the processing list. The processor considers only on-line channels in this assignment selection. Upon the failure of a channel that has messages assigned thereto, these messages will be reassigned to other on-line channels by a back-up channel that has been previously identified with the failed channel. Thus, messages are processed as expeditiously as possible by load sharing.