Process and Thread Priorities in the Sculptor Server¶
Since Sculptor version 6.0.3 by default, the Sculptor server programs runs at PROCESS_PRIORITY_ABOVE_NORMAL. This setting can be changed in the Sculptor Server Manager before starting the server or by starting the server with the command line option –pN, where N is the Sculptor process priority number.
The main thread in the Sculptor server, which only listens for new connections, runs at THREAD_PRIORITY_ABOVE_NORMAL.
Client threads that are servicing Sculptor file access commands and other short duration requests run at THREAD_PRIORITY_NORMAL. A client can change this by calling the set_thread_priority() function.
The priority of a client thread that is executing a Sculptor SQL query is reduced to THREAD_PRIORITY_BELOW_NORMAL while it runs the execute phase of the query. The thread’s previous priority is restored for the fetch phase. This logic is still under test and may be changed in the future. In particular, the logic will probably be modified to reduce the priority by one level from the current level during the execute phase.