Patent ID: 8321842

Claim:
A method for implementing replay-time-only functionalities in a virtual machine of a virtualized computer system, the virtual machine supporting the execution of guest software, the method comprising: determining if the virtual machine is in a replay mode; determining if a functionality included in a computer program in the guest software is a replay-time-only functionality, the computer program including at least a replay-time-only functionality and a functionality that is not a replay-time-only functionality; if the virtual machine is determined to be in the replay mode and if the functionality included in the computer program in the guest software is determined to be a replay-time-only functionality, then sequentially performing the following sequence of steps: pausing the replaying of the virtual machine; saving state information of the virtual machine; executing a core functionality of the replay-time-only functionality; restoring the virtual machine to a state that existed prior to the execution of the core functionality of the replay-time-only functionality; and resuming the replaying of the virtual machine.