Postgres + Heroku SSL SYSCALL错误

Question

偶尔我在Heroku上托管的Rails应用程序将关闭，我不确定发生了什么。有时很多请求超时错误可能会事先发生。然后我得到这个错误： 有没有人知道可能发生了什么，或者我可能会进一步研究这个问题？

NilClass# (PG::Error) "SSL SYSCALL error: EOF detected\n" 


/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/postgresql_adapter.rb:294:in `exec'/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/postgresql_adapter.rb:294:in `dealloc' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/postgresql_adapter.rb:278:in `block in clear' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/postgresql_adapter.rb:277:in `each_value' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/postgresql_adapter.rb:277:in `clear' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/postgresql_adapter.rb:339:in `clear_cache!' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/postgresql_adapter.rb:352:in `reconnect!' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract_adapter.rb:219:in `verify!' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract/connection_pool.rb:333:in `block in checkout_and_verify' 
/app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.12/lib/active_support/callbacks.rb:403:in `_run__2596940609290925681__checkout__3309272650293367200__callbacks' 
/app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.12/lib/active_support/callbacks.rb:405:in `__run_callback' 
/app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.12/lib/active_support/callbacks.rb:385:in `_run_checkout_callbacks' 
/app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.12/lib/active_support/callbacks.rb:81:in `run_callbacks' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract/connection_pool.rb:332:in `checkout_and_verify' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract/connection_pool.rb:253:in `block (2 levels) in checkout' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract/connection_pool.rb:242:in `loop' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract/connection_pool.rb:242:in `block in checkout' 
/usr/local/lib/ruby/1.9.1/monitor.rb:201:in `mon_synchronize' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract/connection_pool.rb:239:in `checkout' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract/connection_pool.rb:102:in `block in connection' 
/usr/local/lib/ruby/1.9.1/monitor.rb:201:in `mon_synchronize' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract/connection_pool.rb:101:in `connection' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract/connection_pool.rb:410:in `retrieve_connection' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract/connection_specification.rb:171:in `retrieve_connection' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract/connection_specification.rb:145:in `connection' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/query_cache.rb:61:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.12/lib/active_record/connection_adapters/abstract/connection_pool.rb:479:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.12/lib/action_dispatch/middleware/callbacks.rb:28:in `block in call' 
/app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.12/lib/active_support/callbacks.rb:405:in `_run__1965518221808316025__call__3309272650293367200__callbacks' 
/app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.12/lib/active_support/callbacks.rb:405:in `__run_callback' 
/app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.12/lib/active_support/callbacks.rb:385:in `_run_call_callbacks' 
/app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.12/lib/active_support/callbacks.rb:81:in `run_callbacks' 
/app/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.12/lib/action_dispatch/middleware/callbacks.rb:27:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.12/lib/action_dispatch/middleware/remote_ip.rb:31:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.12/lib/action_dispatch/middleware/debug_exceptions.rb:16:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.12/lib/action_dispatch/middleware/show_exceptions.rb:56:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.12/lib/rails/rack/logger.rb:32:in `call_app' 
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.12/lib/rails/rack/logger.rb:16:in `block in call' 
/app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.12/lib/active_support/tagged_logging.rb:22:in `tagged' 
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.12/lib/rails/rack/logger.rb:16:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.12/lib/action_dispatch/middleware/request_id.rb:22:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.5/lib/rack/methodoverride.rb:21:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.5/lib/rack/runtime.rb:17:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/activesupport-3.2.12/lib/active_support/cache/strategy/local_cache.rb:72:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.5/lib/rack/lock.rb:15:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.12/lib/action_dispatch/middleware/static.rb:62:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/rack-cache-1.2/lib/rack/cache/context.rb:136:in `forward' 
/app/vendor/bundle/ruby/1.9.1/gems/rack-cache-1.2/lib/rack/cache/context.rb:245:in `fetch' 
/app/vendor/bundle/ruby/1.9.1/gems/rack-cache-1.2/lib/rack/cache/context.rb:185:in `lookup' 
/app/vendor/bundle/ruby/1.9.1/gems/rack-cache-1.2/lib/rack/cache/context.rb:66:in `call!' 
/app/vendor/bundle/ruby/1.9.1/gems/rack-cache-1.2/lib/rack/cache/context.rb:51:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.12/lib/rails/engine.rb:479:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.12/lib/rails/application.rb:223:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.12/lib/rails/railtie/configurable.rb:30:in `method_missing' 
/app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.5/lib/rack/static.rb:119:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.5/lib/rack/content_length.rb:14:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.12/lib/rails/rack/log_tailer.rb:17:in `call' 
/app/vendor/bundle/ruby/1.9.1/gems/thin-1.5.0/lib/thin/connection.rb:81:in `block in pre_process' 
/app/vendor/bundle/ruby/1.9.1/gems/thin-1.5.0/lib/thin/connection.rb:79:in `catch' 
/app/vendor/bundle/ruby/1.9.1/gems/thin-1.5.0/lib/thin/connection.rb:79:in `pre_process' 
/app/vendor/bundle/ruby/1.9.1/gems/thin-1.5.0/lib/thin/connection.rb:54:in `process' 
/app/vendor/bundle/ruby/1.9.1/gems/thin-1.5.0/lib/thin/connection.rb:39:in `receive_data' 
/app/vendor/bundle/ruby/1.9.1/gems/eventmachine-1.0.0/lib/eventmachine.rb:187:in `run_machine' 
/app/vendor/bundle/ruby/1.9.1/gems/eventmachine-1.0.0/lib/eventmachine.rb:187:in `run' 
/app/vendor/bundle/ruby/1.9.1/gems/thin-1.5.0/lib/thin/backends/base.rb:63:in `start' 
/app/vendor/bundle/ruby/1.9.1/gems/thin-1.5.0/lib/thin/server.rb:159:in `start' 
/app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.5/lib/rack/handler/thin.rb:13:in `run' 
/app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.5/lib/rack/server.rb:268:in `start' 
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.12/lib/rails/commands/server.rb:70:in `start' 
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.12/lib/rails/commands.rb:55:in `block in <top (required)>' 
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.12/lib/rails/commands.rb:50:in `tap' 
/app/vendor/bundle/ruby/1.9.1/gems/railties-3.2.12/lib/rails/commands.rb:50:in `<top (required)>' 
script/rails:6:in `require' 
script/rails:6:in `<main>' 

Answer 1

下面的链接可能是一个起点：

https://devcenter.heroku.com/articles/postgres-logs-errors#pgerror-ssl-syscall-error-eof-detected

特别是以下摘录：

These errors indicate a client side violation of the wire protocol. This happens for one of two reasons:

• The Postgres connection is shared between more than one process or thread. Typical offenders are Resque workers or Unicorn. Be sure to correctly establish the PG connection after the fork or thread has initialized to resolve this issue.

• Abrupt client (application side) disconnections. This can happen for many reasons, from your app crashing, to transient network availability. When your app tries to issue a query again against postgres, the connection is just gone, leading to a crash. When Heroku detects a crash, we migrate kill that dyno and start a new one, which re-establishes the connection.

我看到了类似的问题，而上面是我希望有一种方法可以真正解决问题（如果您无法阻止客户端崩溃服务器，那么这似乎是次优的）。我已经向Heroku提交了一张票，因此会通知我是否还有其他事情...

更新：这里是另一个可能相关的链接：https://github.com/rails/rails/issues/9421。