Software that caches strings in computer memory, often used for web sites
Memcached
Developer(s)
Danga Interactive
Initial release
May 22, 2003 (2003-05-22)
Stable release
1.6.26[1]
/ 27 March 2024; 41 days ago (27 March 2024)
Repository
github.com/memcached/memcached
Written in
C
Operating system
Cross-platform
Type
distributed memory caching system
License
Revised BSD license[2]
Website
memcached.org
Memcached (pronounced variously mem-cash-dee or mem-cashed) is a general-purpose distributed memory-caching system. It is often used to speed up dynamic database-driven websites by caching data and objects in RAM to reduce the number of times an external data source (such as a database or API) must be read. Memcached is free and open-source software, licensed under the Revised BSD license.[2] Memcached runs on Unix-like operating systems (Linux and macOS) and on Microsoft Windows. It depends on the libevent library.
Memcached's APIs provide a very large hash table distributed across multiple machines. When the table is full, subsequent inserts cause older data to be purged in least recently used (LRU) order.[3][4] Applications using Memcached typically layer requests and additions into RAM before falling back on a slower backing store, such as a database.
Memcached has no internal mechanism to track misses which may happen. However, some third party utilities provide this functionality.
Memcached was first developed by Brad Fitzpatrick for his website LiveJournal, on May 22, 2003.[5][6] It was originally written in Perl, then later rewritten in C by Anatoly Vorobey, then employed by LiveJournal.[7] Memcached is now used by many other systems, including YouTube,[8] Reddit,[9] Facebook,[10][11] Pinterest,[12][13] Twitter,[14] Wikipedia,[15] and Method Studios.[16] Google App Engine, Google Cloud Platform, Microsoft Azure, IBM Bluemix and Amazon Web Services also offer a Memcached service through an API.[17][18][19][20]
^"Release 1.6.26". 27 March 2024. Retrieved 23 April 2024.
^"Google Code Archive - Long-term storage for Google Code Project Hosting". Code.google.com. Retrieved 2017-06-25.
^"Google Code Archive - Long-term storage for Google Code Project Hosting". Code.google.com. Retrieved 2017-06-25.
^[1]. Community.livejournal.com (2003-05-22). Retrieved on 2013-09-18.
^[2]. Community.livejournal.com (2003-05-27). Retrieved on 2013-09-18.
^"lj_dev: memcached". 2013-02-25. Archived from the original on 2013-02-25. Retrieved 2017-06-25.
^Cuong Do Cuong (Engineering manager at YouTube/Google) (June 23, 2007). Seattle Conference on Scalability: YouTube Scalability (Online Video - 26th minute). Seattle: Google Tech Talks.
^Whitaker, Keir (2010-05-17). "Steve Huffman on Lessons Learned at Reddit | Carsonified". Archived from the original on 2010-05-17. Retrieved 2017-06-25.
^"Scaling memcached at Facebook". Facebook.com. 2008-12-12. Retrieved 2017-06-25.
^Scaling Memcache at Facebook. USENIX. 2002. ISBN 9781931971003. Retrieved 2017-06-25.
^"Building Pinterest in the cloud". Pinterest Careers. 2013-06-19. Retrieved 2018-03-09.
database or API) must be read. Memcached is free and open-source software, licensed under the Revised BSD license. Memcached runs on Unix-like operating...
metrics with Redis or Memcached". 10 December 2015. Retrieved 2016-10-24. "Collecting ElastiCache metrics + its Redis/Memcached metrics". 10 December...
the memcached project, who had founded a company, NorthScale, to develop a key-value store with the simplicity, speed, and scalability of memcached, but...
protocol as memcached, so applications may use any memcached API as a means of accessing a MemcacheDB database. MemcacheQ is a MemcacheDB variant that...
understand how cache stampedes occur, consider a web server that uses memcached to cache rendered pages for some period of time, to ease system load....
Conference & Expo. He is also the maintainer of the C client library for the Memcached server. He also maintains the current version of Gearman. He is a commentator...
software platform that includes Apache, PHP (with PEAR and Smarty), shards, Memcached, Squid, Perl, ImageMagick and Java; the system administration tools include...
LiveJournal and is the author of a variety of free software projects such as memcached, PubSubHubbub, OpenID, and Perkeep. Born in Iowa, Fitzpatrick grew up...
the web server and the web browser. Its most important feature is using memcached for caching the data in memory. MMCache is free software released under...
optimizer, higher transactional throughput in InnoDB, new NoSQL-style memcached APIs, improvements to partitioning for querying and managing very large...
general caching of queries and memoization, Reddit uses memcached behind Facebook's memcached router, mcrouter. In 2017, it had almost 3.3 terabytes of...
ends, MySQL at the database back end, Sphinx on the two search systems, memcached for caching SQL queries and PHP-sessions and Varnish in front of Lighttpd...
Cloud Memorystore – Managed in-memory data store based on Redis and Memcached. Local SSD: High-performance, transient, local block storage. Filestore:...
need to use a persistent storage layer, e.g. a network cache such as Memcached or Redis, or local cache (disk or memory based) to record the availability...
dictionary. Links to diverse learning resources – page curated by the memcached project. Scalable Definition – by The Linux Information Project (LINFO)...
disk. This allows for faster data access and retrieval. Examples: Redis, Memcached. Time-series databases: Time-series databases are optimized for handling...
Retrieved March 26, 2015. "Introduction to Intel Ethernet Flow Director and Memcached Performance" (PDF). Intel. October 14, 2014. Retrieved October 11, 2015...
Global Information
/ 27 March 2024