puma v4 では SIGTERM での worker process ゾンビ化に気をつけよう / Be aware of zombie processes in puma v4

Meguro.rb#29 LT で話した内容です！
puma v4 では「worker process に SIGTERM を送ると zombie process が生まれる」という挙動に変わりました。これが原因で問題が起きた弊社の経験を踏まえて、puma v4 で zombie process に気をつけようという話をしました。
https://megurorb.connpass.com/event/140137/

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   κϯϏԽʹؾΛ͚ͭΑ͏ 31.Jul.2019 - Nao Minami (@south37) Wantedly, Inc. Meguro.rb #29
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