Search results
Results from the WOW.Com Content Network
Paged allocation divides the computer's primary memory into fixed-size units called page frames, and the program's virtual address space into pages of the same size. The hardware memory management unit maps pages to frames. The physical memory can be allocated on a page basis while the address space appears contiguous.
The memory model specifies synchronization barriers that are established via special, well-defined synchronization operations such as acquiring a lock by entering a synchronized block or method. The memory model stipulates that changes to the values of shared variables only need to be made visible to other threads when such a synchronization ...
Memory management (also dynamic memory management, dynamic storage allocation, or dynamic memory allocation) is a form of resource management applied to computer memory.The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their request, and free it for reuse when no longer needed.
When the operating system requested memory to load a program, or a program requested more memory to hold data from a file for instance, it would call the memory handling library. This examined the mappings to look for an area in main memory large enough to hold the request. If such a block was found, a new entry was entered into the table.
A process is said to own resources, of which an image of its program (in memory) is one such resource. However, in multiprocessing systems many processes may run off of, or share, the same reentrant program at the same location in memory, but each process is said to own its own image of the program.
The three-state process management model is designed to overcome this problem, by introducing a new state called the BLOCKED state. This state describes any process which is waiting for an I/O event to take place. In this case, an I/O event can mean the use of some device or a signal from another process. The three states in this model are:
There are different ways of defining the elements that make up an operating model. People, process and technology is one commonly used definition, [1] process, organization and technology is another. [2] An organization is a complex system for delivering value. An operating model breaks this system into components, showing how it works.
In computer engineering, a register–memory architecture is an instruction set architecture that allows operations to be performed on (or from) memory, as well as registers. [1] If the architecture allows all operands to be in memory or in registers, or in combinations, it is called a "register plus memory" architecture.