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An example run of the distributed snapshot protocol in a three-process distributed system is shown in Figure 2.8. P₀ is the initiator of the round of the global checkpointing. P₀ takes a local checkpoint and sends a Marker message along each of its outing channels. Upon receiving the Marker message, P₁ immediately takes a local checkpoint and in turn sends a Marker message to each of its outgoing channels. Similarly, P₂ takes a local checkpoint when it receives the first Marker message (from P₁) and sends a Marker message to each of its outgoing channels connecting to P₀ and P₁, respectively.

Upon taking a local checkpoint, a process starts logging messages, if any, arrived at each incoming channel. The process stops logging messages for a channel as soon as it has received a Marker message from that channel. The messages logged will become the state for each channel. For P₀, the channel state consists of a message m₀. For P₁, the channel state consists of a message m₁. The channel state for P₂ is empty because it did not receive any message prior to the receipt of the Marker message from each of its incoming channels. Note that the regular message received (such as m₀ or m₁) is executed immediately, which is drastically different from the Tamir and Sequin global checkpointing protocol.

Figure 2.8 Normal operation of the Chandy and Lamport global snapshot protocol in an example three-process distributed system.