Patent ID: 7430493

Claim:
A time correcting method for event trace data to make a correction to time of occurrence of an event contained in the event trace data in which the event occurring at time of executing programs on a plurality of computers is stored as time-series data, said method comprising: a first step of calculating a clock skew value being a difference in operations of clocks built-in in said plurality of computers to be measured; and a second step of correcting the time of occurrence of the event contained in said event trace data collected by executing a given program on said plurality of computers to be measured by applying said clock skew value obtained in said first step, wherein said first step comprises: a step of collecting event trace data by executing a transmitting program on one computer selected from said plurality of computers and a receiving program on another computer selected from said plurality of computers; and a step of calculating the clock skew value being the difference in operations of the clocks built-in in said computers by an analysis of the collected event trace data, in which a plurality of transmitted events contained in the event trace data collected from said one computer on which said transmitting program was run are made to exactly correspond to a plurality of received events contained in said event trace data collected from said other computer on which said receiving program was run and then a required period of time for communications is calculated from a difference in time of occurrence of said transmitted event corresponding to the time of occurrence of received event and finally a clock skew value is obtained by approximating a change in the required period of time for the communications corresponding to the time of occurrence of received event using a linear equation.