Regula Document Reader is not general HTTP webserver, that handles hundreds of request per second. Typical document processing takes up to a few seconds, so we can call it CPU intensive. Considering that typical instance has 1-4 workers, we need to carefully manage workers time. One of the main sources of waisting worker's processing time is slow clients problem. When webservice receives request from client with a slow internet connection, free worker start receiving that request. The worker will be bottlenecked by the speed of the client connection, and it will be blocked until the slow client finishes sending large ID image. Being blocked means that this worker process can not handle any other request in the meantime, it’s just there, idle, waiting to receive the entire request, so it can start really processing it.