The fundamental task of any modern operating system is process management.
The operating system must allocate resources to processes, enable
processes to share and exchange information, protect the resources of each
process from other processes, and enable synchronization among processes.To meet
these requirements, the operating system must maintain a data structure for each
process that describes the state and resource ownership of that process and that enables
the operating system to exert process control.
On a multiprogramming uniprocessor, the execution of multiple processes can
be interleaved in time. On a multiprocessor, not only may process execution be interleaved,
but also multiple processes can execute simultaneously. Both interleaved
and simultaneous execution are types of concurrency and lead to a host of difficult
problems, both for the application programmer and the operating system.
In many contemporary operating systems, the difficulties of process management
are compounded by the introduction of the concept of thread. In a multithreaded
system, the process retains the attributes of resource ownership, while the
attribute of multiple, concurrent execution streams is a property of threads running
within a process.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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