Wiki source code of Performance

Version 56.1 by Thomas Mortagne on 2015/05/18

version	line-number	content
22.1	1	{{box cssClass="floatinginfobox" title="Contents"}}
	2	{{toc/}}
	3	{{/box}}
20.1	4
17.1	5	Here are some tips to increase XWiki's performance.
10.1	6
49.1	7	= Clustering =
	8
	9	If you need high availability or if the load on your XWiki instance is too high you can [[configure XWiki in a cluster>>platform:AdminGuide.Clustering]] to spread the load.
	10
48.1	11	= Standalone Solr =
	12
	13	By default XWiki ships with an embedded Solr. If you have a lot of wiki pages (for example in a wiki farm with lots of subwikis), the embedded Solr may use up too much memory and CPU and in this case it's a good idea to externalize Solr on a different server. To do so:
50.1	14
48.1	15	* [[Download and install Solr>>https://cwiki.apache.org/confluence/display/solr/Installing+Solr]]
	16	* [[Configure XWiki to use an external Solr instance>>extensions:Extension.Solr Search API\|\|anchor="HConfiguration"]]
	17
55.1	18	You can also find more Solr specific performances details on [[https://wiki.apache.org/solr/SolrPerformanceProblems]].
54.1	19
42.1	20	= Slow random number generation on UNIX =
	21
46.1	22	The library used for random number generation in Sun's JVM relies on ##/dev/random## by default for UNIX platforms.
42.1	23
48.3	24	Although ##/dev/random## is more secure, it's possible to use ##/dev/urandom## if the default JVM configuration instead.
42.1	25
	26	To determine if your operating system exhibits this behavior, try displaying a portion of the file from a shell prompt:
	27
45.1	28	{{code language="bash"}}
42.1	29	head -n 1 /dev/random
45.1	30	{{/code}}
42.1	31
46.1	32	If the command returns immediately, you can use ##/dev/random## as the default generator for SUN's JVM. If the command does not return immediately, use these steps to configure the JVM to use ##/dev/urandom##:
42.1	33
44.1	34	1. Open the ##$JAVA_HOME/jre/lib/security/java.security## file in a text editor.
	35	1. Change the line:
50.1	36	{{code language="properties"}} securerandom.source=file:/dev/random{{/code}}
42.1	37	to read:
50.1	38	{{code language="properties"}} securerandom.source=file:/dev/urandom{{/code}}
44.1	39	1. Save your change and exit the text editor.
42.1	40
20.2	41	= Gzip compression and caching of static pages =
14.1	42
20.1	43	We're working on making these features part of the XWiki core (see [[XWIKI-2022>>http://jira.xwiki.org/jira/browse/XWIKI-2022]]). While waiting for this to be natively implemented, the recommended solution is to set up an Apache Web Server in front of your servlet container and install/configure the following modules:
14.1	44
20.1	45	* [[mod-deflate>>http://httpd.apache.org/docs/2.0/mod/mod_deflate.html]]
	46	* [[mod-expire>>http://httpd.apache.org/docs/2.0/mod/mod_expires.html]]
	47	* [[mod-proxy-ajp>>http://httpd.apache.org/docs/2.2/mod/mod_proxy_ajp.html]] (note that this depends on [[mod-proxy>>http://httpd.apache.org/docs/2.2/mod/mod_proxy.html]] that you also need to install)
	48
14.1	49	Modify your Apache configuration file to load the different modules:
	50
20.1	51	{{code language="none"}}
14.1	52	LoadModule expires_module /usr/lib/apache2/modules/mod_expires.so
	53	LoadModule deflate_module /usr/lib/apache2/modules/mod_deflate.so
	54	LoadModule proxy_module /usr/lib/apache2/modules/mod_proxy.so
	55	# Depends: proxy
	56	LoadModule proxy_ajp_module /usr/lib/apache2/modules/mod_proxy_ajp.so
20.1	57	{{/code}}
14.1	58
37.1	59	//Alternatively you can run the following commands as root (sudo)//
	60
	61	{{code language="bash"}}
	62	a2enmod deflate
	63	a2enmod proxy_ajp
	64	a2enmod expires
	65	{{/code}}
	66
32.2	67	and configure your different modules as described below:
14.1	68
20.2	69	== Mod Deflate Configuration ==
14.1	70
20.1	71	{{code language="none"}}
14.1	72	vwwwpro-1:~# cat /etc/apache2/conf.d/deflate
	73	<Location />
	74	# Insert filter
	75	SetOutputFilter DEFLATE
	76
	77	# Netscape 4.x has some problems...
	78	BrowserMatch ^Mozilla/4 gzip-only-text/html
	79
	80	# Netscape 4.06-4.08 have some more problems
20.1	81	BrowserMatch ^Mozilla/4.0[678] no-gzip
14.1	82
	83	# MSIE masquerades as Netscape, but it is fine
20.1	84	# BrowserMatch bMSIE !no-gzip !gzip-only-text/html
14.1	85
	86	# NOTE: Due to a bug in mod_setenvif up to Apache 2.0.48
	87	# the above regex won't work. You can use the following
	88	# workaround to get the desired effect:
20.1	89	BrowserMatch bMSI[E] !no-gzip !gzip-only-text/html
14.1	90
	91	# Don't compress images
20.1	92	SetEnvIfNoCase Request_URI .(?:gif\|jpe?g\|png)$ no-gzip dont-vary
14.1	93
	94	# Make sure proxies don't deliver the wrong content
	95	#Header append Vary User-Agent env=!dont-vary
	96	</Location>
20.1	97	{{/code}}
14.1	98
37.1	99	//On debian apache2 the config file for deflate is located under /etc/apache2/mods-enabled/deflate.conf//
	100
20.2	101	== Mod Expire Configuration ==
14.1	102
20.1	103	{{code language="none"}}
14.1	104	vwwwpro-1:~# cat /etc/apache2/conf.d/expires
	105	<Location /xwiki/skins/>
	106	ExpiresActive on
	107	ExpiresDefault "access plus 1 day"
	108	</Location>
	109
	110	<Location /xwiki/bin/skin/>
	111	ExpiresActive on
	112	ExpiresDefault "access plus 1 day"
	113	</Location>
20.1	114	{{/code}}
14.1	115
20.2	116	== Mod Proxy AJP Configuration ==
14.1	117
20.1	118	{{code language="none"}}
	119	ProxyRequests Off
14.1	120	<Proxy *>
	121	Order deny,allow
	122	Allow from all
	123	</Proxy>
	124	ProxyPreserveHost On
	125	ProxyPass /xwiki ajp://192.168.1.181:8009/xwiki
20.1	126	{{/code}}
14.1	127
20.1	128	where ##ajp:~/~/192.168.1.181:8009/xwiki## is the internal address of your Servlet container where XWiki is running.
14.1	129
37.1	130	If you use Tomcat(7) you need to enable the ajp connector in the /etc/tomcat7/server.xml. Comment out the following line with adding {{code}}<!-- -->{{/code}}. //Maybe give a comment why you did it.//
	131
	132	{{code}}
	133	<!-- disable to use ajp connector instead
	134	<Connector port="8080" protocol="HTTP/1.1"
	135	connectionTimeout="20000"
	136	URIEncoding="UTF-8"
	137	redirectPort="8443" />
	138	-->
	139	{{/code}}
	140
39.1	141	Uncomment the following line by removing the {{code}}<!-- -->{{/code}} and add {{code}}URIEncoding="UTF-8"{{/code}} to it.Maybe give a comment too.
37.1	142
	143	{{code}}
	144	<!-- Activate ajp connector for apache proxy_ajp -->
	145	<Connector port="8009" protocol="AJP/1.3" redirectPort="8443" URIEncoding="UTF-8"/>
	146	{{/code}}
	147
20.2	148	= Memory =
9.1	149
34.1	150	You need to configure your Servlet container so that XWiki has enough memory. You'll need to tune the value to your need. You should check the logs and see if there are any "out of memory" errors. Here are some good default values:
36.1	151
53.1	152	* Small installs: A minimum of 512MB of heap memory and 196MB of permGen (##-Xmx512m -XX:MaxPermSize=196m##)
	153	* Medium installs: 1024MB for the heap and 196MB of permGen (##-Xmx1024m -XX:MaxPermSize=196m##)
	154	* Large installs: 2048MB (or beyond) for the heap and 196MB of permGen (##-Xmx2048m -XX:MaxPermSize=196m##).
9.1	155
53.3	156	{{info}}
53.1	157	You should not increase the memory beyond what you need because increasing it means that there's more Objects in memory at any time and the automatic JVM Garbage Collector has to work harder to clean itself, which can results in performance degradation in XWiki (since a full GC will pause the application for a longer time).
53.3	158	{{/info}}
53.1	159
34.1	160	{{warning}}
	161	Note that storing attachments with the default (in database) storage mechanism is very memory intensive. See the [[administrators guide to attachments>>platform:AdminGuide.Attachments]] for more information about memory cost and the alternative filesystem based attachment store.
38.2	162
	163	Also note that uploading a lot of pages can trigger out of memory (OOM) errors due to scheduled watchlist jobs. For example uploading 1 million pages will trigger OOM errors even when the JVM is configured to run with 2GB of heap space. For such kind of load we recommend to disable (unschedule) the Watchlist jobs (in ##/xwiki/bin/view/Scheduler/##) before uploading the pages.
34.1	164	{{/warning}}
20.1	165
35.1	166	For your information here are the values used for the xwiki.org site:
	167
	168	{{code}}
53.2	169	CATALINA_OPTS="-server -Xms800m -Xmx1480m -XX:MaxPermSize=222m -Dfile.encoding=utf-8 -Djava.awt.headless=true -XX:+UseParallelGC -XX:MaxGCPauseMillis=100"
35.1	170	{{/code}}
	171
20.2	172	= Database Indexes =
1.1	173
32.2	174	Make sure you've set [[Database indexes>>Database Administration]]. This is especially important when you start having lots of documents.
1.1	175
20.2	176	= Panels =
1.1	177
32.2	178	Some panels take more resources than others. For example the Navigation panel should NOT be used for wikis with a lot of documents since it displays all documents in the wiki. In the future that panel should be improved for performance but that's not the case right now. Originally this panel was only meant as a starting point. A better approach is to use a "Quick Links Panel" as we've now set up in the default XWiki Enterprise wiki version 1.1 (we've removed the default usage of the Navigation Panel in that version).
1.1	179
20.2	180	= Robots.txt =
15.1	181
32.2	182	If your wiki is open on the Internet, it'll be crawled by search robots (like GoogleBot, etc). They will call all the URLs and especially the ones that are resource hungry like exports (PDF/RTF). You need to protect against this. To do so configure a ##robots.txt## file like this one and put it in your webserver configuration:
15.1	183
20.1	184	{{code language="none"}}
15.1	185	User-agent: *
22.1	186	Disallow: /xwiki/bin/attach/
	187	Disallow: /xwiki/bin/cancel/
	188	Disallow: /xwiki/bin/commentadd/
	189	Disallow: /xwiki/bin/delattachment/
	190	Disallow: /xwiki/bin/delete/
	191	Disallow: /xwiki/bin/dot/
	192	Disallow: /xwiki/bin/download/
	193	Disallow: /xwiki/bin/downloadrev/
15.1	194	Disallow: /xwiki/bin/edit/
22.1	195	Disallow: /xwiki/bin/export/
	196	Disallow: /xwiki/bin/get/
15.1	197	Disallow: /xwiki/bin/inline/
22.1	198	Disallow: /xwiki/bin/lifeblog/
	199	Disallow: /xwiki/bin/login/
	200	Disallow: /xwiki/bin/loginerror/
	201	Disallow: /xwiki/bin/logout/
	202	Disallow: /xwiki/bin/objectremove/
	203	Disallow: /xwiki/bin/pdf/
15.1	204	Disallow: /xwiki/bin/preview/
	205	Disallow: /xwiki/bin/propadd/
	206	Disallow: /xwiki/bin/propdelete/
22.1	207	Disallow: /xwiki/bin/propupdate/
	208	Disallow: /xwiki/bin/register/
	209	Disallow: /xwiki/bin/save/
15.1	210	Disallow: /xwiki/bin/skin/
	211	Disallow: /xwiki/bin/status/
22.1	212	Disallow: /xwiki/bin/upload/
	213	Disallow: /xwiki/bin/viewattachrev/
15.1	214	Disallow: /xwiki/bin/viewrev/
22.1	215	Disallow: /xwiki/bin/xmlrpc/
	216	# It could be also usefull to block certain spaces from crawling,
	217	# especially if this spaces doesn't provide new content
	218	Disallow: /xwiki/bin/view/Main/
	219	Disallow: /xwiki/bin/view/XWiki/
	220	# on the other hand you would like to have your recent (public) changes included
	221	Allow: /xwiki/bin/view/Main/Dashboard
20.1	222	{{/code}}
15.1	223
32.1	224
32.2	225	Note:
32.1	226
32.2	227	For Tomcat6 the placement of the ##robots.txt## file should be within the //$TOMCAT/webapps/ROOT// folder and should have permission 644 applied.
32.1	228
	229	{{code}}
	230	-rw-r--r-- 1 root www 1478 Jan 8 15:52 robots.txt
	231	{{/code}}
	232
32.2	233	In order to test if the ##robots.txt## file is either accessable or working as desired use this [[checker>>http://www.frobee.com/robots-txt-check]].
32.1	234
20.2	235	= Statistics =
1.1	236
20.1	237	{{info}}
	238	This is no longer true starting with XE 1.4M2 since statistics are now put on a queue and written in a different thread in the database in one go, thus reducing the overhead to a maximum.
	239	{{/info}}
15.1	240
32.2	241	The statistics module is off by default since it's quite database intensive. If you don't need it you should turn it off.
1.2	242
20.2	243	= Monitoring =
7.1	244
20.1	245	More a developer-oriented feature, XWiki can monitor its own code, reporting the time spent for each sub-component activated during a request. While the monitoring code isn't time consuming, it increases the memory consumption a bit, and the create/start/stop/log/destroy calls are spread all around the code, so you will save a lot of method calls by disabling this. You can do that by setting the following line in ##xwiki.cfg##:
	246
	247	{{code language="null"}}
19.1	248	xwiki.monitor=0
20.1	249	{{/code}}
7.1	250
52.3	251	= Document Cache =
1.2	252
52.3	253	You can tune the Document cache in the ##xwiki.cfg## configuration file. The value depends on how much memory you have. The higher the better. A good reasonable value is 1000.
2.1	254
20.1	255	{{code language="none"}}
19.1	256	xwiki.store.cache.capacity=1000
20.1	257	{{/code}}
8.1	258
25.1	259	= Cache Macro =
	260
26.1	261	It's possible to perform selective content caching by using the [[Cache Macro>>extensions:Extension.Cache Macro]].
25.1	262
51.1	263	= LESS Cache =
	264
52.2	265	[[LESS>>extensions:Extension.LESS Module]] is a preprocessor used to generate CSS files for skins and skin extensions. See the [[Performance section>>extensions:Extension.LESS Module\|\|anchor="HPerformances"]] of the LESS module documentation to learn more about how to optimize this cache for performances.
51.1	266
20.2	267	= Rendering cache =
2.1	268
30.1	269	Some pages are complex to render (they may aggregate outside data for example or do complex and slow queries). For theses pages you can use rendering cache.
	270
29.1	271	== Configuration based ==
25.1	272
32.2	273	Pages can be cached (i.e. their rendered content cached) to speed up displaying. The configuration is done in ##xwiki.properties## with the following configuration options:
25.1	274
	275	{{code language="none"}}
	276	#-# [Since 2.4M1]
	277	#-# Indicate if the rendering cache is enabled.
	278	#-# Default value is false.
	279	# core.renderingcache.enabled=true
	280
	281	#-# [Since 2.4M1]
	282	#-# A list of Java regex patterns matching full documents reference.
	283	# core.renderingcache.documents=wiki:Space\.Page
	284	# core.renderingcache.documents=wiki:Space\..*
	285
	286	#-# [Since 2.4M1]
	287	#-# The time (in seconds) after which data should be removed from the cache when not used.
	288	#-# Default value is 300 (5 min).
	289	# core.renderingcache.duration=300
	290
	291	#-# [Since 2.4M1]
	292	#-# The size of the rendering cache. Not that it's not the number of cached documents but the number of cached results.
	293	#-# (For a single document several cache entries are created, because each action, language and request query string
	294	#-# produces a unique rendering result)
	295	#-# Default value is 100.
	296	# core.renderingcache.size=100
	297	{{/code}}
	298
31.1	299	You can force a page to refresh using ##refresh=1## in the URL.
30.1	300
41.1	301	Since 6.2 it's also possible to programmatically refresh any document cache using ##com.xpn.xwiki.internal.cache.rendering.RenderingCache## component:
39.1	302
	303	{{code language="java"}}
	304	@Inject
	305	private RenderingCache renderingCache;
	306
	307	...
	308
	309	renderingCache.flushWholeCache();
	310	renderingCache.flushCache(new DocumentReference("xwiki", "MySpace", "MyCachedDocument"));
	311	{{/code}}
	312
28.1	313	== Enabled using velocity in document content itself (XWiki 1.0 syntax only) ==
25.1	314
30.1	315	You can add the following to their content to cache them after they are rendered. Note that the document is refreshed whenever the content of the document changes, and the cache takes into account the URL, so it is pretty safe to add a long cache duration for all documents that don't contain scripts gathering data from the wiki. For example to cache the rendered content for 60 seconds you would add:
2.1	316
20.1	317	{{code language="none"}}
19.1	318	$context.setCacheDuration(60)
20.1	319	{{/code}}
2.1	320
20.1	321	Since 1.5M2, you can set the default rendering cache duration for all pages in ##xwiki.cfg##:
	322
	323	{{code language="none"}}
16.1	324	## cache all rendered documents for one hour
	325	xwiki.rendering.defaultCacheDuration=3600
20.1	326	{{/code}}
	327
16.1	328	Setting the default cache duration to a large value, and manually disabling the cache in dynamic pages would really speed up the wiki, since the rendering is one of the most time consuming processes.
	329
20.2	330	= Merge the CSS files =
11.1	331
32.2	332	In order to reduce the number of requests and files that are downloaded from the browser or client, it could help to merge all XWiki CSS files into a single one. See the [[Merge CSS Script>>extensions:Extension.Merge CSS]].
11.1	333
20.2	334	= Set up NginX =
19.2	335
32.2	336	If you experience //__heavy loads__// on your wiki, you could try using NginX.
19.3	337
36.1	338	NginX is used to fetch static content: images, javascript, styles, etc, but it can also be used as a reverse-proxy to pass requests down to the web container (e.g. Tomcat on port 8080).
19.2	339
32.2	340	Unlike Apache, which instantiates a new process per every static file, NginX uses the same process to fetch all the static data, and thus gives you extra perfomance "for free".
19.2	341
32.2	342	For more info on setting up NginX check [[this guide>>NginX]].
19.2	343
20.2	344	= Backlinks =
4.1	345
20.1	346	While a pretty neat feature, keeping track of the backlinks has a medium impact on the document saving time and a minor impact on the document loading time. If you feel that your wiki does not need backlinks, you can safely disable them with the following line in ##xwiki.cfg##:
	347
	348	{{code language="none"}}
19.1	349	xwiki.backlinks=0
20.1	350	{{/code}}
5.1	351
20.2	352	= Versioning =
5.1	353
32.2	354	One of the key features of any wiki system, versioning greatly affects the database size and the document update time. If you are sure your wiki does not need to keep track of all the changes and you will never need to revert documents to a previous version, then you can add the following line in ##xwiki.cfg##:
20.1	355
	356	{{code language="none"}}
19.1	357	xwiki.store.versioning=0
20.1	358	{{/code}}
6.1	359
21.1	360	= Custom Mapping =
6.1	361
32.2	362	In some cases you may not want to rely on XWiki's generic database schema for storing XClass data and instead you'd like to provide your own optimized table. For these use cases you can use [[Custom Mapping>>platform:DevGuide.CustomMapping]].
21.1	363
	364	= Wiki syntax features for XWiki Syntax 1.0 =
	365
47.1	366	If you're using XWiki Syntax 1.0 and if you don't plan to use all of the markup features, like the strikethrough filter, the automatic http links filter, the SVG, Laszlo or style macros, you can disable them in ##xwiki-core-.jar/META-INF/services/com.xpn.xwiki.render.##. The wiki rendering is the most costly operation in the rendering process, so any disabled feature counts.
	367
	368	Now this will have no effect if you're using another syntax, like XWiki Syntax 2.x.
56.1	369
	370	= Performance tree =
	371
	372	Since 7.1 it's possible to directly get a tree of time spent in each step of the request by using [[debug mode>>dev:Community.Debugging\|\|anchor="HDebugmode"]].

Wiki source code of Performance

Quick Links

Navigation

About

About

Support

Platform

User Guide

Admin Guide

Developer Guide

Projects

XWiki

Extensions

Other

Contribute

Status

Practices

Under the Hood

Get Involved

Get Connected