read-modify-write
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Names in other languages
- caLlegir-modificar-escriure
- Englishread-modify-write
- УкраїнськаRead-modify-write
- 中文Read-modify-write
- 日本語リード・モディファイ・ライト
- DeutschRMW-Befehl
- 한국어읽기-수정-쓰기
Article bodies are English and are not machine-translated. A name in another language is not a translation of the article.
In computer science, read–modify–write is a class of atomic operations (such as test-and-set, fetch-and-add, and compare-and-swap) that both read a memory location and write a new value into it simultaneously, either with a completely new value or some function of the previous value. These operations prevent race conditions in multi-threaded applications. Typically they are used to implement mutexes or semaphores. These atomic operations are also heavily used in non-blocking synchronization. Read–modify–write instructions often produce unexpected results when used on I/O devices, as a write operation may not affect the same internal register that would be accessed in a read operation. This term is also associated with RAID levels that perform actual write operations as atomic read–modify–write sequences. Such RAID levels include RAID 4, RAID 5 and RAID 6.
Text derived from https://en.wikipedia.org/w/index.php?oldid=1360580985 under CC BY-SA 4.0; modifications have been made.
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