decremented exit guard when failed to write header #37

merged 2 commits into from Oct 12, 2013

2 participants


I think Twiggy fails to decrement exit_guard counter when, it fails to write response header (i.e EPIPE).
I have not written a test yet but this pull request should fix the problem. Please tell me if I am wrong in any ways.


Can you write a test, or at least how to reproduce the problem? Thanks!


Thanks for the response! I would write test and come back.


Hi @miyagawa san I have added a test.

Let me explain problems I am facing in detail. I have implemented Chat Online Server with Twiggy::Prefork and Server::Starter.

In our production environment, we see IO Error when writing header on rare occasion.

What happens then, is that Twiggy's exit_guard fails to decrement as I have written previously. And When we try to restart a process by HUP signal or process reaches max-request-per-client, the process stops to accept new connection and wait until all request are served, but this condition is never met due to exit_guard decrement failure and process hangs forever.

@miyagawa miyagawa merged commit 761545e into miyagawa:master Oct 12, 2013

Thanks as lot!

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