您可能应该看到
the Heroku devcenter article,因为这些信息会更有帮助,这里有一个小小的总结：
要回答超时问题：
Cedar supports long-polling and streaming responses. Your app has an initial 30 second window to respond with a single byte back to the client. After each byte sent (either recieved from the client or sent by your application) you reset a rolling 55 second window. If no data is sent during the 55 second window your connection will be terminated.
(也就是说,如果你有Cedar而不是Aspen或Bamboo,你可以每隔30秒左右发送一个字节来欺骗系统.它可能会起作用.)
要回答你的dynos问题：
Additional concurrency is of no help whatsoever if you are encountering request timeouts. You can crank your dynos to the maximum and you’ll still get a request timeout,since it is a single request that is failing to serve in the correct amount of time. Extra dynos increase your concurrency,not the speed of your requests.
(也就是说,不要费心添加更多的dynos.)
request timeouts：
检查代码是否存在无限循环,如果你正在做大事：
If so,you should move this heavy lifting into a background job which can run asynchronously from your web request. See 07002 for details.
