In computer science, buffer data (or just buffer ) is a physical memory storage area used to temporarily store data when moved from one place to another. Typically, data is stored in a buffer as it is taken from an input device (such as a microphone) or just before it is sent to an output device (such as a speaker). However, buffers can be used when moving data between processes within the computer. This is proportional to the buffer in telecommunications. Buffers can be implemented in fixed memory locations in hardware - or by using virtual data buffers in software, pointing to locations in physical memory. In all cases, data stored in the data buffer is stored on physical storage media. Most of the buffers are implemented in software, which usually uses faster RAM to store data temporarily, because access times are much faster compared to hard disk drives. Buffers are typically used when there is a difference between the rate at which data is received and the rate at which it can be processed, or in the case that the tariff is variable, for example in a printer spooler or in an online video stream.
Buffers often adjust time by implementing a queue (or FIFO) algorithm in memory, simultaneously writing data into a queue at one level and reading it at another rate.
Video Data buffer
Apps
Buffers are often used in conjunction with I/O to hardware, such as disk drives, sending or receiving data to or from the network, or playing sound on speakers. The line to the rollercoaster at the amusement park shares many similarities. People who ride a coaster come at an unknown and often volatile speed, but a roller coaster will be able to load people in bursts (as coasters arrive and load). The queue area acts as a buffer - temporary space where those who want to ride wait until a ride is available. Buffers are typically used in the FIFO method (first in, first out), generating data in the sequence arriving.
Buffers can improve application performance by allowing sync operations such as read or write files to resolve quickly instead of blocking while waiting for hardware interrupts to access the physical disk subsystem; instead, the operating system can immediately return successful results from API calls, allowing the app to continue processing while the kernel completes disk operations in the background. Further benefits can be achieved if the application reads or writes small data blocks that do not fit the disk subsystem block size, allowing buffers to be used to combine many smaller read or write operations into more efficient block sizes. for the disk subsystem, or in the case of reading, sometimes to completely avoid having to access the disk physically.
Maps Data buffer
Telecommunication buffer
A buffer or storage routine used in telecommunications compensates for differences in data flow rates, or when events occur, when transferring data from one device to another.
Buffers are used for many purposes, including:
- Connect two digital circuits that operate at different levels,
- Save data for later use,
- Allows time correction to be made on the data stream,
- Collect binary data bits into groups that can then be operated as units,
- Delay signal transit time to enable another operation to occur.
Buffer versus cache
Caches often also serve as buffers, and vice versa. However, the cache operates on the premise that the same data will be read from them multiple times, that the written data will be read soon, or that there is a good chance of some reading or writing to be combined to form a larger block. Their only goal is to reduce access to slower bottom storage. A cache is usually also an abstraction layer designed to be invisible.
"Disk Cache" or "File Cache" stores statistics on the data contained therein and performs the data in the time period runs out in write-back mode. Buffer does not do this.
Buffers are mainly used for input, output, and sometimes very transient data storage between other media or data that can be modified non-sequentially before being written (or read) sequentially.
Example
- The command/statement BUFFERS in CONFIG.SYS DOS.
- Buffer between serial port (UART) and MODEM. COM port speed may be 38400 bit/s while MODEM may only have 14400 bit/s carrier.
- Built in stand on Hard Disk Drive, Printer or other hardware.
- Framebuffer on video card.
History
The initial mention of the print buffer is Customers designed by Russel A. Kirsch's image pioneer for SEAC computers in 1952:
One of the most important problems in automated digital computer design is to get calculated results from the machine quickly enough to avoid delaying further calculation progress. In many of the problems where a general purpose computer is applied, the amount of output data is relatively large - so large that serious inefficiency will result from forcing the computer to wait for this data to be typed on existing printing devices. This difficulty has been solved in SEAC by providing magnetic recording devices as output units. This device can receive information from the engine at speeds up to 100 times as fast as the electric typewriter can be operated. Thus, better efficiency is achieved in recording output data; transcriptions can be made later from the magnetic recording device to the printing device without binding to the main computer.
See also
- Bucket (computing)
- Buffer overflow
- Buffer underrun
- Circular support
- Disk buffer
- Streaming media
- Frame buffer for use in chart view
- Double buffering and Triple buffering for techniques especially in graphics
- Buffer depth, Stencil buffer, for various pieces of image information
- The variable length buffer
- Optical buffer
- MissingNo., the result of the data buffer is not cleared properly in PokÃÆ'Â © mon Red and Blue
- UART buffer
- ENOBUFS, POSIX error caused by lack of memory in buffer
- Write a buffer, a type of memory buffer
- 512k days
References
Source of the article : Wikipedia
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