abort requests that are taking too long

 A generous timeout of 15s is the default. It's recommended to set the timeout
 as low as realistically viable for your application. Most applications will
 do fine with a setting between 2 and 5 seconds.
 .
 Rack::Timeout is not a solution to the problem of long-running requests,
 it's a debug and remediation tool. App developers should track rack-timeout's
 data and address recurring instances of particular timeouts.