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The Tamir and Sequin global checkpointing protocol is very elegant. However, it is a blocking protocol in that normal execution is suspended during each round of global checkpointing. For applications that do not wish to suspend the normal execution for potentially extensive period of time, the Chandy and Lamport distributed snapshot protocol [5] might be more desirable.

The Chandy and Lamport distributed snapshot protocol [5] is a nonblocking protocol in that normal execution is not interrupted by the global checkpointing. However, unlike the Tamir and Sequin protocol, the Chandy and Lamport distributed snapshot protocol only concerns on how to produce a consistent global checkpoint, and it prescribes no mechanisms on how to determine the end of the checkpointing round, and how to atomically switch over to the new global checkpoint.

Figure 2.7 Finite state machine specification for the Chandy and Lamport distributed snapshot protocol.