Chris Johnson, Index

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Software Design Techniques: Fault Tolerance

• Recovery blocks:
  - write acceptance tests for modules;
  - if it fails then execute alternative.
  
  
• Must be able to restore the state:
  - take a snapshot/checkpoint;
  - if failure restore snapshot.
  
  
• But:
  - if failed module have side-effects?
  - eg effects on equip under control?
  - recovery block will be complicated.
  
  
• Different from execptions:
  - dont rely on run-time system.

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