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Checkpointing can be found in the rendermanrendersettings node under Rendering → Render → Checkpoint Render

Checkpoint Exit at

You can use this parameter to set a time in hour / minutes / seconds for the renderer to exit.  If a sequence of frames is being rendered, then the renderer will move onto the next frame in the sequence.

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• 60s - this is 60 seconds
• 60m - this is 60 minutes
• 60h - this is 60 hours
• 60d - this is 60 days
  
  

Therefore, to exit a render after 5 minutes, enter 5m.  The image grid below demonstrates checkpointing at 1m, 2m, 5m, 10m

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