METHOD FOR WARMING UP A SPARE PROCESS IN A REPLICATED REAL-TIME SYSTEM, IN PARTICULAR IN A TELEPHONE EXCHANGE

摘要

The invention relates to a method for warming up a spare process in parallel with an active process in a replicated real-time switching system, in particular in a telephone exchange. The switching system comprises an active control unit (WP) having, permanently or when necessary, a replicating hot-standby spare unit (SP) connected to a common internal message bus, so that the spare unit performs the same processes as the active control unit in parallel. In accordance with the invention, the operation of the active process ( sigma ) to be replicated is temporarily frozen in the active control unit (WP) when the process has no tasks to be performed, the other processes of the active control unit simultaneously being kept in operation. After this a spare process ( sigma ) is created to the spare unit (SP), and the state data ( sigma ) of the active process is loaded into the spare process. Provided that no new tasks have come in during this time to the active process ( sigma ), the warm-up is found successful. The warm-up is found failed if new tasks have come in.