Search results
Results from the WOW.Com Content Network
Memory segmentation is an operating system memory management technique of dividing a computer's primary memory into segments or sections.In a computer system using segmentation, a reference to a memory location includes a value that identifies a segment and an offset (memory location) within that segment.
In operating systems, memory management is the function responsible for managing the computer's primary memory. [1]: 105–208 The memory management function keeps track of the status of each memory location, either allocated or free. It determines how memory is allocated among competing processes, deciding which gets memory, when they receive ...
However, on the 80386, with its paged memory management unit it is possible to protect individual memory pages against writing. [4] [5] Memory models are not limited to 16-bit programs. It is possible to use segmentation in 32-bit protected mode as well (resulting in 48-bit pointers) and there exist C language compilers which support that. [6]
However, segment registers are usually used implicitly. All CPU instructions are implicitly fetched from the code segment specified by the segment selector held in the CS register. Most memory references come from the data segment specified by the segment selector held in the DS register. These may also come from the extra segment specified by ...
Segment registers, fundamental to the older 8088 and 80286 MMU designs, are not used in modern OSes, with one major exception: access to thread-specific data for applications or CPU-specific data for OS kernels, which is done with explicit use of the FS and GS segment registers. All memory access involves a segment register, chosen according to ...
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.
Segment descriptor; Segmentation fault; Shadow memory; Shadow RAM (Acorn) Shared graphics memory; Shared memory; Sideways address space; Soft reference; Stack-based memory allocation; Static variable; Storage violation
Region-based memory management works best when the number of regions is relatively small and each contains many objects; programs that contain many sparse regions will exhibit internal fragmentation, leading to wasted memory and a time overhead for region management. Again, in the presence of region inference this problem can be more difficult ...