Which three are direct benefits of the multiprocess, multithreaded architecture of Oracle Database 12c when it is enabled?
A.Reduced logical I/O
B.Reduced virtual memory utilization
C.Improved parallel Execution performance
D.Improved Serial Execution performance
E.Reduced physical I/O
F.Reduced CPU utilization
Oracle Database 12c: New Features for Administrators 20 — 23
Multi-Process Multi-Threaded Architecture: Benefits and Setup
• CPU and memory usage reduction
• Better system reliability
• Better performance for parallel operations
The Multi-Process (MP) model makes every Oracle process run as a separate OS process. This model suffers from inefficient resource utilization and sharing.
Starting with Oracle Database 12c, the multithreaded Oracle (MT) model enables certain Oracle processes to execute as operating system threads in the same address space. In threaded mode, some background processes on UNIX and Linux run as processes (processes containing one thread), whereas the remaining Oracle processes run as threads within OS processes. The OS process to Oracle process allocation is random based. This is what is called the Multi-Process / Multi-Threaded hybrid architecture.
• As of Oracle Database 12c release 12.1, and because of their importance, it was decided to always have PMON, DBW, VKTM, and PSP running as OS processes. This can change in future releases.
• Each OS process also runs a special thread called SCMN, which is basically an internal listener thread. All thread creation is routed through this thread. This special thread is not shown in the slide.