OS Multimedia Process Scheduling

OSs that support multimedia differs from the traditional ones (OSs that doesn't support multimedia) in the following three ways:

Process scheduling
The file system
Disk scheduling

Let's discuss briefly about process scheduling.

Scheduling Homogeneous Process

The simplest type of video server is the one that can support the display of a fixed number of movies, all using the same frame rate, video resolution, data rate, and some other parameters.

General Real-Time Scheduling

In this model, the number of users changes as viewers come and go, frame sizes vary widely due to the video compression nature and different movies may have different resolutions, the scheduling of more than one competing processes, some/all of which have deadlines that must be met is called as real-time scheduling.

Real Monotonic Scheduling

The classic static real-time scheduling algorithm for preemptable periodic processes is Rate Monotonic Scheduling or RMS in short.

The rate monotonic scheduling can be used for the processes that met the following five conditions:

Each and every periodic process must be completed within its period.
No any process is dependent on any other process.
Each and every process needs the same amount of central processing unit time on each burst.
Any non-periodic processes have no deadlines.
Process preemption occurs instantaneously and with no any overhead.

Earliest Deadline First Scheduling

Earliest deadline first is basically a dynamic algorithm that doesn't require the processes to be periodic as does the rate monotonic algorithm. Nor does it require the same run time per central processing unit burst, as does rate monotonic scheduling.