What do you mean by address mapping?
Address Mapping. A related choice is the granularity of address mapping, which is defined as the smallest unit of addressed data (from the persistent store) that can be mapped independently to an area of the virtual address space.
The memory mapping process is handled by the virtual memory manager, which is the same subsystem responsible for dealing with the page file. Memory mapped files are loaded into memory one entire page at a time. The page size is selected by the operating system for maximum performance.
- 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 naturally implements demand paging, because file contents are not read from disk initially and do not use physical RAM at all.
- Direct Mapping Technique: The simplest way of associating main memory blocks with cache block is the direct mapping technique. In this technique, block k of main memory maps into block k modulo m of the cache, where m is the total number of blocks in cache. The main memory address is divided into three fields.
- In computing and data management, data mapping is the process of creating data element mappings between two distinct data models. Data mapping is used as a first step for a wide variety of data integration tasks, including: Data transformation or data mediation between a data source and a destination.
Memory-mapped I/O. So when an address is accessed by the CPU, it may refer to a portion of physical RAM, or it can instead refer to memory of the I/O device. Thus, the CPU instructions used to access the memory can also be used for accessing devices.
- Picture source : IO Devices. I/O devices are mapped into a separate address space. This is usually accomplished by having a different set of signal lines to indicate a memory access versus a port access. The address lines are usually shared between the two address spaces, but less of them are used for accessing ports.
- Address space is the amount of memory allocated for all possible addresses for a computational entity, such as a device, a file, a server, or a networked computer. Address space may refer to a range of either physical or virtual addresses accessible to a processor or reserved for a process.
- IOPS is the standard unit of measurement for I/O (Input/Output) operations per second. This measurement is a performance-based measurement and is usually seen written as: Total IOPS: Average number of I/O operations per second. Read IOPS: Average number of read I/O operations per second.
A driver sends commands or data to a device by storing into its device register, or retrieves status or data from a device by reading from its device register. Many processors use memory-mapped I/O, which maps device registers to fixed addresses in the conventional memory space.
- Memory-mapped files (MMFs) offer a unique memory management feature that allows applications to access files on disk in the same way they access dynamic memory—through pointers. With this capability you can map a view of all or part of a file on disk to a specific range of addresses within your process's address space.
- Memory-mapped I/O is something you can do reasonably well in standard C and C++. Device drivers communicate with peripheral devices through device registers. A driver sends commands or data to a device by storing into its device register, or retrieves status or data from a device by reading from its device register.
- Address Mapping. A related choice is the granularity of address mapping, which is defined as the smallest unit of addressed data (from the persistent store) that can be mapped independently to an area of the virtual address space.
Updated: 17th October 2018