The purpose of this article is to provide a basic definition for both HTTP Client Workers and HTTP Concurrent Connections as well as provide some documentation related to both statistics.
Usually, when a client connection begins (after the TCP Handshake), the client will send an HTTP request (normally a GET request). This will create a new HTTP worker until a response is received. After that, the client can send more HTTP requests within the same TCP connection, so new HTTP workers will be created and killed for each one of those requests.
There can be connections without HTTP workers, but in order to have a worker, we require an existing connection. For this reason, the number of concurrent connections is usually higher than the number of HTTP workers.
Each ProxySG model has its own HTTP concurrent connections and HTTP workers’ limit. It’s important to note that this limit applies to both statistics, so both of them should always be checked when troubleshooting performance issues.