08df111f___6_0_39____The_Host_Container__Description
[Attribute] backgroundProcessorDelay [Description] 
This value represents the delay in seconds between the invocation of the backgroundProcess method on this host and its child containers, including all contexts. Child containers will not be invoked if their delay value is not negative (which would mean they are using their own processing thread). Setting this to a positive value will cause a thread to be spawn. After waiting the specified amount of time, the thread will invoke the backgroundProcess method on this host and all its child containers. A host will use background processing to perform live web application deployment related tasks. If not specified, the default value for this attribute is -1, which means the host will rely on the background processing thread of its parent engine.
Apache Tomcat Configuration Reference (6.0.39) - The Host Container
Description