On UNIX, starting with Oracle Database 12c Release 2 (12.2), Oracle Database can use an operating system process or an operating system thread to implement each background task such as database writer (
DBW0), log writer (
LGWR), shared server process dispatchers, and shared servers.
The use of operating system threads instead of processes allow resource sharing and reduce resource consumption.
On Windows, each background process is implemented as a thread inside a single, large process. For each Oracle Database instance or system identifier, there is one corresponding process for Oracle Database. For example, 100 Oracle Database processes for a database instance on UNIX are handled by 100 threads inside one process on Windows.
All Oracle Database background, dedicated server, and client processes are threads of the master Oracle Database Windows process, and all threads of the Oracle Database process share resources. This multithreaded architecture is highly efficient, allowing fast context switches with low overhead.
To view processes or end individual threads, use Oracle Administration Assistant for Windows. From the Start menu, select All Programs, then select Oracle - HOMENAME, then select Configuration and Migration Tools, and then select Administration Assistant for Windows. Right-click the
SID and choose Process Information.
Microsoft Management Console (MMC) is started when Oracle Administration Assistant for Windows is started. Oracle Database has integrated several database administration snap-ins into Microsoft Management Console.