Patent ID: 7085948
Filing Date: 2006-08-01
Classification: G06F

Abstract:
1. A method for implementing time synchronization correction correction in a first computer system and a second computer system, the first and second computer systems having independent clocks, said method comprising the steps of: providing a common timer resource accessible by each of the computer systems; receiving a request to synchronize the second computer system's clock to the first computer system's clock by the first computer system; responsive to said request, the first computer system starting said common timer resource, reading a time of day from the first computer system's clock, building and sending a set time of day message to the second computer system; responsive to receiving said set time of day message, the second computer system reading said time of day from the first computer system's clock from said set time of day message, reading an elapsed time from said common timer resource, adding said elapsed time to said time of day from the first computer system's clock, and writing a result to the second computer system's clock: receiving a request to synchronize the first computer system's clock to the second computer system's clock by the first computer system; responsive to said request, the first computer system building and sending a get time of day message to the second computer system; responsive to receiving said get time of day message, the second computer system reading said time of day from the second computer system's clock; and starting said common timer resource; the second computer system sending a reply message to the first computer system including said read time of day from the second computer system's clock; the first computer system, reading said time of day from the second computer system's clock from said reply message, reading an elapsed time from said common timer resource, adding said elapsed time to said time of day from the second computer system's clock, and writing a result to the first computer system's clock.