CPU Multitasking Time-Slice Simulator

OS CPU time-slice allocation

The complete coloured rings are the allocation plan. The clock hands move through those already-allocated time slices; they do not create the slices as they move.

60 PRE-ALLOCATED SLICES PER CORE

Current slice

of 60

Physical cores

single-core CPU

Running simultaneously

maximum 1

Applications

allocated before playback

Full rotations

completed

OS allocation overview applications are distributed across cores before the clocks run

Main memory allocation applications remain in memory between CPU slices

An application can have memory allocated while waiting for its next CPU time slice.

Current time slice

Allocation complete

All 60 time slices on each active core have already been assigned. The hand is pointing at slice 1.

Processes executing now Word Processor on Core 1

Key idea: only the process whose allocated slice is under a core's hand is executing on that core at this instant.

Selected core · Core 1 Word Processor

Slice 1 of 60 · allocated applications: Word Processor, Music Player, Clock

Processor configuration

Single-core processor

One core processes one time slice at a particular instant. The hand moves rapidly between slices allocated to different processes.

How to read the clock

RINGAll sectors are allocated before playback starts. Colours identify the process allocated each slice.

HANDPoints at the one slice currently being processed on that core.

NOW RUNNINGShows the application/process that owns the slice under the hand.

MULTI-COREEvery physical core has its own hand and can process one slice simultaneously.

Accuracy & scope

Teaching model: an application is simplified to one runnable process and its core assignment is kept stable for one demonstration. Real operating systems make scheduling decisions dynamically and may migrate threads/processes between cores. The clock is therefore a visual model of CPU-time sharing, not a literal future schedule stored by an operating system.