The optional space management coordinator process (SMCO) schedules various space management tasks, including proactive space allocation and space reclamation. SMCO dynamically spawns space management worker processes (Wnnn) to implement these tasks. After starting, the worker acts as an autonomous agent. After it finishes a task, the worker process automatically picks up another task from the queue. The process terminates itself after being idle for a long time.
Wnnn worker processes (named W001, W002, and so on) perform tasks on behalf of Space Management and the Oracle Database In-Memory option.
For Space Management, Wnnn processes perform space management tasks in the background, including the following:
- Preallocate space into locally managed tablespace and SecureFiles segments based on space usage growth analysis.
- Create and manage the temporary tablespace metadata and reclaims space from orphaned temporary segments.
- Reclaim space from dropped segments.
- Perform fast ingest deferred inserts.
For the Oracle Database In-Memory option, Wnnn processes perform the following tasks:
- Prepopulate in-memory enabled objects with priority LOW/MEDIUM/HIGH/CRITICAL and repopulate in-memory objects for the in-memory coordinator background process (IMCO).
- Initiate in-memory populate and repopulate tasks for IMCO foreground processes in response to queries and DMLs that reference in-memory enabled objects.
Both SMCO and Wnnn can run as threads or as operating system processes.