3.2.2.3 Monitor concept

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**Figure 3.11:** Monitoring concept
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A central instance administers the limited resources (hard disks, video, memory).

Best suited for competitive processes.
Access on resources via special functions whose are offered and realized by the monitoring process (X11, PVM-daemon).

Differences between semaphore and monitoring concept :

Semaphores : Processes ''talk to each other''.
Monitoring :

Central instance receives jobs from the processes, e.g., pizza service.

Gundolf Haase 2000-03-20