捕获TERM并发送QUIT后，Heroku上的独角兽退出超时

Question 1

我收到一个运行独角兽和sidekiq的Heroku应用程序的R12退出超时错误。每当我部署时，这些错误每天都会发生1-2次。我知道我需要转换Heroku的关闭信号以使独角兽正确响应，但我认为我已经在以下独角兽配置中这样做了：

worker_processes 3
timeout 30
preload_app true

before_fork do |server, worker|
  Signal.trap 'TERM' do
    puts "Unicorn master intercepting TERM and sending myself QUIT instead. My PID is #{Process.pid}"
    Process.kill 'QUIT', Process.pid
  end

  if defined?(ActiveRecord::Base)
    ActiveRecord::Base.connection.disconnect!
    Rails.logger.info('Disconnected from ActiveRecord')
  end
end

after_fork do |server, worker|
  Signal.trap 'TERM' do
    puts "Unicorn worker intercepting TERM and doing nothing. Wait for master to sent QUIT. My PID is #{Process.pid}"
  end

  if defined?(ActiveRecord::Base)
    ActiveRecord::Base.establish_connection
    Rails.logger.info('Connected to ActiveRecord')
  end

  Sidekiq.configure_client do |config|
    config.redis = { :size => 1 }
  end
end

我的错误日志如下所示：

Stopping all processes with SIGTERM
Unicorn worker intercepting TERM and doing nothing. Wait for master to sent QUIT. My PID is 7
Unicorn worker intercepting TERM and doing nothing. Wait for master to sent QUIT. My PID is 11
Unicorn worker intercepting TERM and doing nothing. Wait for master to sent QUIT. My PID is 15
Unicorn master intercepting TERM and sending myself QUIT instead. My PID is 2
Started GET "/manage"
reaped #<Process::Status: pid 11 exit 0> worker=1
reaped #<Process::Status: pid 7 exit 0> worker=0
reaped #<Process::Status: pid 15 exit 0> worker=2
master complete
Error R12 (Exit timeout) -> At least one process failed to exit within 10 seconds of SIGTERM
Stopping remaining processes with SIGKILL
Process exited with status 137

看来，所有子进程在超时之前都已成功获得。主人可能还活着吗？另外，如日志所示，路由器在关闭期间是否仍应向dyno发送Web请求？

FWIW，我正在使用Heroku的零停机部署插件（https://devcenter.heroku.com/articles/labs-preboot/）。

Question 2

我认为您的自定义信号处理是造成此处超时的原因。

编辑：我因不同意Heroku的文档而感到沮丧，我想解决这个问题。

配置Unicorn应用程序以捕获并吞下TERM信号是最可能导致应用程序挂起且无法正确关闭的原因。

Heroku似乎认为，捕获TERM信号并将其转换为QUIT信号是将硬关机变为正常关机的正确行为。

但是，在某些情况下，执行此操作似乎会导致完全不关机的风险-此错误的根源。遇到运行独角兽的悬挂式测功机的用户，应考虑证据并根据首要原则（而不只是文档）做出自己的决定。