Just Die Already

I'm not religious, but I'm definitely spiritual. Programs, like living creatures, need to die.

Program that run forever are zombies. They're cancers. They're unnatural.

Programs that are born and die are living. They're healthy. They're natural.

Let's look at some common cancers and some healthy software.

Transcript

1. Just Die Already
   

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2. State
   

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3. App Servers
   

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4. • Runtime
   • Application
   • Socket
   • Database
   • Cache
   • Worker threads
   “Stateless”
   

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5. Software Ageing
   gradual degradation of application performance, over time,
   that may lead to premature program termination
   

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6. What sucks?
   

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7. Rails.
   

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9. Old news?
   

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10. “400  restarts  a  
    mother  fucking  
    day”
    

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11. Leeks
    

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12. •Memory
    •Locks
    •File descriptors
    •Sockets
    •Threads
    

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13. Recovery
    

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15. @hourly  pgrep  Rails  |  head  -­‐1  |  xargs  kill
    

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16. Passenger
    

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17. That. Is Crazy.
    

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18. Databases
    

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19. The Ultimate Single
    Point of Failure
    

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20. What sucks?
    

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21. SQL.
    

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23. Recovery
    

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26. Event Sourcing
    Martin Fowler’s
    

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28. Soft Deletes
    

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29. acts_as_audited
    

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31. Tests
    

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32. Software Testing
    Doesn’t Scale
    

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33. The Argument
    • Feature testing is effective.
    • Fast changing systems are unstable.
    • Complexity is inevitable.
    • Inter-feature testing is ineffective.
    

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34. What sucks?
    

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35. “Identical to production”
    

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36. #OccupyProduction
    

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37. Recovery
    

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39. Acceptance
    Integration
    Unit
    Run in Production
    Run in Production
    Yeah, nah.
    

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40. Multi-Version
    Concurrency
    

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41. “But what if I break
    production?”
    

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42. “But when I break
    production?”
    

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44. •Crash
    •Undo
    •Instrument
    

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45. Recovery-Oriented
    Computing
    http://roc.cs.berkeley.edu/
    

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46. fin
    

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