you mean what type of server? this program runs on different types of servers. Mostly Apache servers.
The process is rebuilding a database. Not a problem for a database that isn't huge. but the process timesout for databases of around 50k messages. Even though there is really nothing wrong with the program.
Look at the Timeout keyword in the Apache config file. You can also dump \0 characters to the client periodically to ensure that it does not time out (vs the server timing out).