Search results
Results From The WOW.Com Content Network
Memory-mapped file. A memory-mapped file is a segment of virtual memory [ 1] that has been assigned a direct byte-for-byte correlation with some portion of a file or file-like resource. This resource is typically a file that is physically present on disk, but can also be a device, shared memory object, or other resource that an operating system ...
mmap. In computing, mmap(2) is a POSIX -compliant Unix system call that maps files or devices into memory. It is a method of memory-mapped file I/O. It implements demand paging because file contents are not immediately read from disk and initially use no physical RAM at all. The actual reads from disk are performed after a specific location is ...
For the airport in Mexico with the code MMIO, see Saltillo Airport. Memory-mapped I/O ( MMIO) and port-mapped I/O ( PMIO) are two complementary methods of performing input/output (I/O) between the central processing unit (CPU) and peripheral devices in a computer (often mediating access via chipset ). An alternative approach is using dedicated ...
PCI devices have a set of registers referred to as configuration space and PCI Express introduces extended configuration space for devices. Configuration space registers are mapped to memory locations. Device drivers and diagnostic software must have access to the configuration space, and operating systems typically use APIs to allow access to ...
A memory management unit ( MMU ), sometimes called paged memory management unit ( PMMU ), [ 1] is a computer hardware unit that examines all memory references on the memory bus, translating these requests, known as virtual memory addresses, into physical addresses in main memory . In modern systems, programs generally have addresses that access ...
Memory access pattern. In computing, a memory access pattern or IO access pattern is the pattern with which a system or program reads and writes memory on secondary storage. These patterns differ in the level of locality of reference and drastically affect cache performance, [1] and also have implications for the approach to parallelism [2] [3 ...
Shared memory. In computer science, shared memory is memory that may be simultaneously accessed by multiple programs with an intent to provide communication among them or avoid redundant copies. Shared memory is an efficient means of passing data between programs. Depending on context, programs may run on a single processor or on multiple ...
A page table is a data structure used by a virtual memory system in a computer to store mappings between virtual addresses and physical addresses. Virtual addresses are used by the program executed by the accessing process, while physical addresses are used by the hardware, or more specifically, by the random-access memory (RAM) subsystem.