MemCached.doc (MediaWiki) - Revision history

Woozle: navbar template

2005-12-07T16:00:47Z

navbar template

← Older revision		Revision as of 16:00, 7 December 2005
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	{{~~web software\|MediaWiki}}: [[MediaWiki Developer Documents~~\|~~Developer Documents]]: [[~~MemCached.doc]]		{{mediawiki dev doc\|MemCached.doc}}

	==Text==		==Text==
	===memcached support for MediaWiki===		===memcached support for MediaWiki===

	From ca August 2003, MediaWiki has optional support for memcached, a "high-performance, distributed memory object caching system". For general information on it, see: http://www.danga.com/memcached/		From ca August 2003, MediaWiki has optional support for memcached, a "high-performance, distributed memory object caching system". For general information on it, see: http://www.danga.com/memcached/

	Memcached is likely more trouble than a small site will need, but for a larger site with heavy load, like Wikipedia, it should help lighten the load on the database servers by caching data and objects in memory.		Memcached is likely more trouble than a small site will need, but for a larger site with heavy load, like Wikipedia, it should help lighten the load on the database servers by caching data and objects in memory.

	====Requirements====		====Requirements====

	* PHP must be compiled with --enable-sockets		* PHP must be compiled with --enable-sockets
	* libevent: http://www.monkey.org/~provos/libevent/		* libevent: http://www.monkey.org/~provos/libevent/
Line 45:		Line 41:
	The wiki should then use memcached to cache various data. To use multiple servers (physically separate boxes or multiple caches on one machine on a large-memory x86 box), just add more items to the array. To increase the weight of a server (say, because it has twice the memory of the others and you want to spread usage evenly), make its entry a subarray:		The wiki should then use memcached to cache various data. To use multiple servers (physically separate boxes or multiple caches on one machine on a large-memory x86 box), just add more items to the array. To increase the weight of a server (say, because it has twice the memory of the others and you want to spread usage evenly), make its entry a subarray:

	~~<pre>~~		NaodW29-pre314ba41d77a1ba100000001
	~~$wgMemCachedServers = array(~~
	~~"127.0.0.1:11000", # one gig on this box~~
	~~array("192.168.0.1:11000", 2) # two gigs on the other box~~
	);
	~~</pre>~~

	====PHP client for memcached====		====PHP client for memcached====

Woozle: MediaWikiDoc:MemCached.doc moved to MemCached.doc (MediaWiki)

2005-12-07T15:17:48Z

MediaWikiDoc:MemCached.doc moved to MemCached.doc (MediaWiki)

← Older revision	Revision as of 15:17, 7 December 2005
(No difference)

Woozle: pasted original contents from hypertwiki, I think

2005-10-14T18:47:29Z

pasted original contents from hypertwiki, I think

← Older revision		Revision as of 18:47, 14 October 2005
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	~~[[Techniques]]:~~		{{web software\|MediaWiki}}: [[MediaWiki Developer Documents\|Developer Documents]]: [[MemCached.doc]]
	~~Software~~: [[MediaWiki~~]]: [[MediaWikiDoc:~~Developer Documents\|Developer
	Documents]]: [[~~MediaWikiDoc:MemCached.doc\|~~MemCached.doc]]
	==Text==		==Text==
	===memcached support for MediaWiki=== From ca August 2003, MediaWiki		===memcached support for MediaWiki===
	has optional support for memcached, a "high-performance, distributed
	memory object caching system". For general information on it, see:		From ca August 2003, MediaWiki has optional support for memcached, a "high-performance, distributed memory object caching system". For general information on it, see: http://www.danga.com/memcached/
	http://www.danga.com/memcached/ Memcached is likely more trouble than a
	small site will need, but for a larger site with heavy load, like		Memcached is likely more trouble than a small site will need, but for a larger site with heavy load, like Wikipedia, it should help lighten the load on the database servers by caching data and objects in memory.
	Wikipedia, it should help lighten the load on the database servers by
	caching data and objects in memory. ====Requirements==== * PHP must be		====Requirements====
	compiled with --enable-sockets * libevent:
	http://www.monkey.org/~provos/libevent/ *:(as of 2003-08-11, 0.7a is		* PHP must be compiled with --enable-sockets
	current) * optionally, epoll-rt patch for Linux kernel:		* libevent: http://www.monkey.org/~provos/libevent/
	:http://www.xmailserver.org/linux-patches/nio-improve.html		*:(as of 2003-08-11, 0.7a is current)
	memcached: http://www.danga.com/memcached/download.bml *:(as of this		* optionally, epoll-rt patch for Linux kernel:
	writing, 1.1.9 is current) Memcached and libevent are under BSD-style		*:http://www.xmailserver.org/linux-patches/nio-improve.html
	licenses. The server should run on Linux and other Unix-like systems...		* memcached: http://www.danga.com/memcached/download.bml
	you can run multiple servers on one machine or on multiple machines on		*:(as of this writing, 1.1.9 is current)
	a network; storage can be distributed across multiple servers, and
	multiple web servers can use the same cache cluster.		Memcached and libevent are under BSD-style licenses.

			The server should run on Linux and other Unix-like systems... you can run multiple servers on one machine or on multiple machines on a network; storage can be distributed across multiple servers, and multiple web servers can use the same cache cluster.


	<center><nowiki>		<center><nowiki>
	******************* W A R N I N G ! ! ! ! ! *********************		******************* W A R N I N G ! ! ! ! ! *********************
	</nowiki></center>		</nowiki></center>
	Memcached has no security or authentication. Please ensure that your		Memcached has no security or authentication. Please ensure that your server is appropriately firewalled, and that the port(s) used for memcached servers are not publicly accessible. Otherwise, anyone on the internet can put data into and read data from your cache.
	server is appropriately firewalled, and that the port(s) used for
	memcached servers are not publicly accessible. Otherwise, anyone on the		An attacker familiar with MediaWiki internals could use this to give themselves developer access and delete all data from the wiki's database, as well as getting all users' password hashes and e-mail addresses.
	internet can put data into and read data from your cache. An attacker
	familiar with MediaWiki internals could use this to give themselves
	developer access and delete all data from the wiki's database, as well
	as getting all users' password hashes and e-mail addresses.
	<center><nowiki>		<center><nowiki>
	******************* W A R N I N G ! ! ! ! ! *********************		******************* W A R N I N G ! ! ! ! ! *********************
	</nowiki></center> ====Setup====		</nowiki></center>
	If you want to start small, just run one memcached on your web server:
	memcached -d -l 127.0.0.1 -p 11000 -m 64 (to run in daemon mode,		====Setup====
	accessible only via loopback interface, on port 11000, using up to 64MB		If you want to start small, just run one memcached on your web server:
	of memory) In your LocalSettings.php file, set: $wgUseMemCached = true;
	$wgMemCachedServers = array( "127.0.0.1:11000" ); The wiki should then		memcached -d -l 127.0.0.1 -p 11000 -m 64
	use memcached to cache various data. To use multiple servers		(to run in daemon mode, accessible only via loopback interface, on port 11000, using up to 64MB of memory)
	(physically separate boxes or multiple caches on one machine on a
	large-memory x86 box), just add more items to the array. To increase		In your LocalSettings.php file, set:
	the weight of a server (say, because it has twice the memory of the
	others and you want to spread usage evenly), make its entry a subarray:		$wgUseMemCached = true;
	<pre> $wgMemCachedServers = array( "127.0.0.1:11000", # one gig		$wgMemCachedServers = array( "127.0.0.1:11000" );
	on this box array("192.168.0.1:11000", 2) # two gigs on the other box		The wiki should then use memcached to cache various data. To use multiple servers (physically separate boxes or multiple caches on one machine on a large-memory x86 box), just add more items to the array. To increase the weight of a server (say, because it has twice the memory of the others and you want to spread usage evenly), make its entry a subarray:
	);
	</pre> ====PHP client for memcached====		<pre>
	As of this writing, MediaWiki includes version 1.0.10 of the PHP		$wgMemCachedServers = array(
	memcached client by Ryan Gilfether <hotrodder@rocketmail.com>.		"127.0.0.1:11000", # one gig on this box
	You'll find some documentation for it in the 'php-memcached'		array("192.168.0.1:11000", 2) # two gigs on the other box
	subdirectory under the present one. We intend to track updates, but if		);
	you want to check for the lastest released version, see		</pre>
	http://www.danga.com/memcached/apis.bml If you don't set
	$wgUseMemCached, we still create a MemCacheClient, but requests to it		====PHP client for memcached====
	are no-ops and we always fall through to the database. If the cache		As of this writing, MediaWiki includes version 1.0.10 of the PHP memcached client by Ryan Gilfether <hotrodder@rocketmail.com>. You'll find some documentation for it in the 'php-memcached' subdirectory under the present one.
	daemon can't be contacted, it should also disable itself fairly
	smoothly. ====Keys used====		We intend to track updates, but if you want to check for the lastest released version, see http://www.danga.com/memcached/apis.bml
	User: :key: $wgDBname:user:id:$sId :ex: wikidb:user:id:51 :stores:
	instance of class User :set in: User::loadFromSession() :cleared by:		If you don't set $wgUseMemCached, we still create a MemCacheClient, but requests to it are no-ops and we always fall through to the database. If the cache daemon can't be contacted, it should also disable itself fairly smoothly.
	User::saveSettings(), UserTalkUpdate::doUpdate() Newtalk: :key:
	$wgDBname:newtalk:ip:$ip :ex: wikidb:newtalk:ip:123.45.67.89 :stores:		====Keys used====
	integer, 0 or 1 :set in: User::loadFromDatabase() :cleared by:		*User:
	User::saveSettings() # ? :expiry set to 30 minutes LinkCache: *:key:		*:key: $wgDBname:user:id:$sId
	$wgDBname:lc:title:$title *:ex:		*:ex: wikidb:user:id:51
	wikidb:lc:title:Wikipedia:Welcome,_Newcomers! *:stores: cur_id of page,		*:stores: instance of class User
	or 0 if page does not exist *:set in: LinkCache::addLink()		*:set in: User::loadFromSession()
			*:cleared by: User::saveSettings(), UserTalkUpdate::doUpdate()

			*Newtalk:
			*:key: $wgDBname:newtalk:ip:$ip
			*:ex: wikidb:newtalk:ip:123.45.67.89
			*:stores: integer, 0 or 1
			*:set in: User::loadFromDatabase()
			*:cleared by: User::saveSettings() # ?
			*:expiry set to 30 minutes

			*LinkCache:
			*:key: $wgDBname:lc:title:$title
			*:ex: wikidb:lc:title:Wikipedia:Welcome,_Newcomers!
			*:stores: cur_id of page, or 0 if page does not exist
			*:set in: LinkCache::addLink()
	*:cleared by: LinkCache::clearBadLink()		*:cleared by: LinkCache::clearBadLink()
	*::should be cleared on page deletion and rename		*::should be cleared on page deletion and rename

Woozle at 12:03, 13 June 2005

2005-06-13T12:03:45Z

New page

[[Techniques]]:
Software: [[MediaWiki]]: [[MediaWikiDoc:Developer Documents|Developer
Documents]]: [[MediaWikiDoc:MemCached.doc|MemCached.doc]]
==Text==
===memcached support for MediaWiki=== From ca August 2003, MediaWiki
has optional support for memcached, a "high-performance, distributed
memory object caching system". For general information on it, see:
http://www.danga.com/memcached/ Memcached is likely more trouble than a
small site will need, but for a larger site with heavy load, like
Wikipedia, it should help lighten the load on the database servers by
caching data and objects in memory. ====Requirements==== * PHP must be
compiled with --enable-sockets * libevent:
http://www.monkey.org/~provos/libevent/ *:(as of 2003-08-11, 0.7a is
current) * optionally, epoll-rt patch for Linux kernel:
*:http://www.xmailserver.org/linux-patches/nio-improve.html *
memcached: http://www.danga.com/memcached/download.bml *:(as of this
writing, 1.1.9 is current) Memcached and libevent are under BSD-style
licenses. The server should run on Linux and other Unix-like systems...
you can run multiple servers on one machine or on multiple machines on
a network; storage can be distributed across multiple servers, and
multiple web servers can use the same cache cluster.
<center><nowiki>
********************* W A R N I N G ! ! ! ! ! ***********************
</nowiki></center>
Memcached has no security or authentication. Please ensure that your
server is appropriately firewalled, and that the port(s) used for
memcached servers are not publicly accessible. Otherwise, anyone on the
internet can put data into and read data from your cache. An attacker
familiar with MediaWiki internals could use this to give themselves
developer access and delete all data from the wiki's database, as well
as getting all users' password hashes and e-mail addresses.
<center><nowiki>
********************* W A R N I N G ! ! ! ! ! ***********************
</nowiki></center> ====Setup====
If you want to start small, just run one memcached on your web server:
memcached -d -l 127.0.0.1 -p 11000 -m 64 (to run in daemon mode,
accessible only via loopback interface, on port 11000, using up to 64MB
of memory) In your LocalSettings.php file, set: $wgUseMemCached = true;
$wgMemCachedServers = array( "127.0.0.1:11000" ); The wiki should then
use memcached to cache various data. To use multiple servers
(physically separate boxes or multiple caches on one machine on a
large-memory x86 box), just add more items to the array. To increase
the weight of a server (say, because it has twice the memory of the
others and you want to spread usage evenly), make its entry a subarray:
<pre> $wgMemCachedServers = array( "127.0.0.1:11000", # one gig
on this box array("192.168.0.1:11000", 2) # two gigs on the other box
);
</pre> ====PHP client for memcached====
As of this writing, MediaWiki includes version 1.0.10 of the PHP
memcached client by Ryan Gilfether <hotrodder@rocketmail.com>.
You'll find some documentation for it in the 'php-memcached'
subdirectory under the present one. We intend to track updates, but if
you want to check for the lastest released version, see
http://www.danga.com/memcached/apis.bml If you don't set
$wgUseMemCached, we still create a MemCacheClient, but requests to it
are no-ops and we always fall through to the database. If the cache
daemon can't be contacted, it should also disable itself fairly
smoothly. ====Keys used====
*User: *:key: $wgDBname:user:id:$sId *:ex: wikidb:user:id:51 *:stores:
instance of class User *:set in: User::loadFromSession() *:cleared by:
User::saveSettings(), UserTalkUpdate::doUpdate() *Newtalk: *:key:
$wgDBname:newtalk:ip:$ip *:ex: wikidb:newtalk:ip:123.45.67.89 *:stores:
integer, 0 or 1 *:set in: User::loadFromDatabase() *:cleared by:
User::saveSettings() # ? *:expiry set to 30 minutes *LinkCache: *:key:
$wgDBname:lc:title:$title *:ex:
wikidb:lc:title:Wikipedia:Welcome,_Newcomers! *:stores: cur_id of page,
or 0 if page does not exist *:set in: LinkCache::addLink()
*:cleared by: LinkCache::clearBadLink()
*::should be cleared on page deletion and rename

*MediaWiki namespace:
*:key: $wgDBname:messages
*:ex: wikidb:messages
*:stores: an array where the keys are DB keys and the values are messages
*:set in: wfMsg(), Article::editUpdates() both call wfLoadAllMessages()
*:cleared by: nothing

*Watchlist:
*:key: $wgDBname:watchlist:id:$userID
*:ex: wikidb:watchlist:id:4635
*:stores: HTML string
*:cleared by: nothing, expiry time $wgWLCacheTimeout (1 hour)
*:note: emergency optimisation only

*IP blocks:
*:key: $wgDBname:ipblocks
*:ex: wikidb:ipblocks
*:stores: array of arrays, for the BlockCache class
*:cleared by: BlockCache:clear()

... more to come ...
==Edit Log==
*'''2005-06-13''' Transcribed from docs for MediaWiki version 1.4.5