pre-emptive multitasking

pre-emptive multitasking

(operating system, parallel)
A type of multitasking where the scheduler can interrupt and suspend ("swap out") the currently running task in order to start or continue running ("swap in") another task. The tasks under pre-emptive multitasking can be written as though they were the only task and the scheduler decides when to swap them. The scheduler must ensure that when swapping tasks, sufficient state is saved and restored that tasks do not interfere.

The length of time for which a process runs is known as its "time slice" and may depend on the task's priority or its use of resources such as memory and I/O.

OS/2, Unix and the Amiga use pre-emptive multitasking.

This contrasts with cooperative multitasking where each task must include calls to allow it to be descheduled periodically.
References in periodicals archive ?
RTMON is pre-emptive multitasking OS which is highly simplified for easy use by the students.
The new solution is aimed at providing fast server speeds using the inbuilt multiprocessor support, pre-emptive multitasking and faster networking of the Mac OS X.
PC/GEOS supports true pre-emptive multitasking, including multiple threads of execution within a single process; dynamic memory management; event-driven programming; nesting, overlapped, and arbitrarily shaped windows; device-independent graphics; bit-mapped and outline fonts; and object-oriented programming.
The powerful UNIX-based core of Mac OS X with features like protected memory and pre-emptive multitasking is tailor-made for the rigorous demands of creative professionals and demanding server environments," said Ron Okamoto, Apple's vice president of Worldwide Developer Relations.
The Ubicom ipOS operating system is a selectable single-tasking or pre-emptive multitasking kernel with a task handler that is designed to eliminate priority inversions, which helps ensure correct behavior and simplify debugging.
Apache runs in Tenon's multi-threaded, pre-emptive multitasking environment, and has been extended with support for WebSTAR plug-ins and AppleScript CGIs.
Fully ROMable, Windows CE features pre-emptive multitasking, a Windows-like GUI, and a standard communication protocol that facilitates Internet access and information sharing with other Windows-based applications.
Full pre-emptive multitasking under Windows 95 and NT allows the operator to perform multiple tasks, such as opening files and printing reports, without jeopardizing vital data collection and alarming.
MachTen provides a complete set of Internet services as well as UNIX and X software development tools, all running in a pre-emptive multitasking environment alongside Macintosh applications.
Applications run faster and use less memory because OS services like pre-emptive multitasking, interprocess communication and dynamic memory management have been carefully optimized.
1, already the fastest Smalltalk available, offers users improved performance and better support for client/server applications through more efficient memory management features, three-tiered client/server support and support for pre-emptive multitasking using threads.
Fully optimized for 32-bit processing and technologies such as pre-emptive multitasking, OnLine Dynamic Server for Windows NT delivers an enterprise database solution for midrange and high-end symmetrical processing (SMP) hardware running Windows NT.