METHOD OF RECORDING PLAYBACK AND RE-EXECUTION OF CONCURRENTLY RUNNING APPLICATION PROGRAM OPERATIONAL COMMANDS USING GLOBAL TIME STAMPS

An operator of a digital computer system issues a series of operational commands to respective concurrently executing application programs. Each application program includes a client executive routine that records the application program's operational commands and an associated time stamp indicating when the operational command was received from the operator. The operational commands and the time stamps are transferred to a core executive program that records a script of the operational commands. The core executive determines from the time stamps a global sequence in which the operator issued the operational commands to the application programs. In a playback mode, the computer system re-executes the application programs by issuing the operational commands from the script memory to the application programs in the determined global sequence. In a preferred embodiment, the core executive determines a sequence identifier for each operational command. During the playback mode, the core executive transmits to a command cache for each application program the respective sequence numbers and operational commands having been issued to the application program, and each client executive consecutively issues the operational commands in its application program's command cache until the sequence identifiers indicate that a next operational command in the global sequence is found in the command cache for another application program, at which time the client executive sends a synchronization message to the client executive of the other application program.