Update keepalive timeout with Router 2.0 settings #190
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Router 2.0 introduced keepalive support. It will close connections idle after 90 seconds https://devcenter.heroku.com/articles/http-routing#keepalives. We want to avoid a situation where they send a request right before puma closes the connection. We can do that by setting it to the same timeout the router uses + some value (such as 5 seconds). This timeout is used in the reactor when buffering unfinished request bodies and waiting for new requests on a still open client connection. If a connection is closed incorrectly and doesn't send a TCP `FIN` this timeout will prevent puma holding onto that connection forever. There is currently a problem in puma 6x and prior with keepalives that causes high request variance puma/puma#3487. So it's recommended that puma users disable keepalive connections by until that problem is fixed upstream: ``` $ heroku labs:enable http-disable-keepalive-to-dyno ```
This matches the current devcenter docs https://devcenter.heroku.com/articles/deploying-rails-applications-with-the-puma-web-server.
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For consistency with the timeout chosen by other languages since #261 landed: - heroku/heroku-buildpack-php#823 - heroku/ruby-getting-started#190 GUS-W-18319007. Signed-off-by: Ed Morley <501702+edmorley@users.noreply.github.com>
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For consistency with the timeout chosen by other languages since #261 landed: - heroku/heroku-buildpack-php#823 - heroku/ruby-getting-started#190 GUS-W-18319007. Signed-off-by: Ed Morley <501702+edmorley@users.noreply.github.com>
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For consistency with the timeouts used by other languages: - heroku/heroku-buildpack-php#823 - heroku/ruby-getting-started#190 - heroku/python-getting-started#263
colincasey
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For consistency with the timeouts used by other languages: - heroku/heroku-buildpack-php#823 - heroku/ruby-getting-started#190 - heroku/python-getting-started#263
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For consistency with the timeout chosen by other languages since #261 landed: - heroku/heroku-buildpack-php#823 - heroku/ruby-getting-started#190 GUS-W-18319007. Signed-off-by: Ed Morley <501702+edmorley@users.noreply.github.com>
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Router 2.0 introduced keepalive support. It will close connections idle after 90 seconds https://devcenter.heroku.com/articles/http-routing#keepalives. We want to avoid a situation where they send a request right before puma closes the connection. We can do that by setting it to the same timeout the router uses + some value (such as 5 seconds).
This timeout is used in the reactor when buffering unfinished request bodies and waiting for new requests on a still open client connection. If a connection is closed incorrectly and doesn't send a TCP
FINthis timeout will prevent puma holding onto that connection forever.There is currently a problem in puma 6x and prior with keepalives that causes high request variance puma/puma#3487. So it's recommended that puma users disable keepalive connections by until that problem is fixed upstream:
GUS-W-19166166