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Version 57.1 by Thomas Mortagne on 2015/05/18
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1 {{box cssClass="floatinginfobox" title="**Contents**"}}
2 {{toc/}}
3 {{/box}}
4
5 Here are some tips to increase XWiki's performance.
6
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
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:
14
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
18 You can also find more Solr specific performances details on [[https://wiki.apache.org/solr/SolrPerformanceProblems]].
19
20 = Slow random number generation on UNIX =
21
22 The library used for random number generation in Sun's JVM relies on ##/dev/random## by default for UNIX platforms.
23
24 Although ##/dev/random## is more secure, it's possible to use ##/dev/urandom## if the default JVM configuration instead.
25
26 To determine if your operating system exhibits this behavior, try displaying a portion of the file from a shell prompt:
27
28 {{code language="bash"}}
29 head -n 1 /dev/random
30 {{/code}}
31
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##:
33
34 1. Open the ##$JAVA_HOME/jre/lib/security/java.security## file in a text editor.
35 1. Change the line:
36 {{code language="properties"}} securerandom.source=file:/dev/random{{/code}}
37 to read:
38 {{code language="properties"}} securerandom.source=file:/dev/urandom{{/code}}
39 1. Save your change and exit the text editor.
40
41 = Gzip compression and caching of static pages =
42
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:
44
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
49 Modify your Apache configuration file to load the different modules:
50
51 {{code language="none"}}
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
57 {{/code}}
58
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
67 and configure your different modules as described below:
68
69 == Mod Deflate Configuration ==
70
71 {{code language="none"}}
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
81 BrowserMatch ^Mozilla/4.0[678] no-gzip
82
83 # MSIE masquerades as Netscape, but it is fine
84 # BrowserMatch bMSIE !no-gzip !gzip-only-text/html
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:
89 BrowserMatch bMSI[E] !no-gzip !gzip-only-text/html
90
91 # Don't compress images
92 SetEnvIfNoCase Request_URI .(?:gif|jpe?g|png)$ no-gzip dont-vary
93
94 # Make sure proxies don't deliver the wrong content
95 #Header append Vary User-Agent env=!dont-vary
96 </Location>
97 {{/code}}
98
99 //On debian apache2 the config file for deflate is located under /etc/apache2/mods-enabled/deflate.conf//
100
101 == Mod Expire Configuration ==
102
103 {{code language="none"}}
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>
114 {{/code}}
115
116 == Mod Proxy AJP Configuration ==
117
118 {{code language="none"}}
119 ProxyRequests Off
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
126 {{/code}}
127
128 where ##ajp:~/~/192.168.1.181:8009/xwiki## is the internal address of your Servlet container where XWiki is running.
129
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
141 Uncomment the following line by removing the {{code}}<!-- -->{{/code}} and add {{code}}URIEncoding="UTF-8"{{/code}} to it.Maybe give a comment too.
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
148 = Memory =
149
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:
151
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##).
155
156 {{info}}
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).
158 {{/info}}
159
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.
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.
164 {{/warning}}
165
166 For your information here are the values used for the xwiki.org site:
167
168 {{code}}
169 CATALINA_OPTS="-server -Xms800m -Xmx1480m -XX:MaxPermSize=222m -Dfile.encoding=utf-8 -Djava.awt.headless=true -XX:+UseParallelGC -XX:MaxGCPauseMillis=100"
170 {{/code}}
171
172 = Database Indexes =
173
174 Make sure you've set [[Database indexes>>Database Administration]]. This is especially important when you start having lots of documents.
175
176 = Panels =
177
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).
179
180 = Robots.txt =
181
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:
183
184 {{code language="none"}}
185 User-agent: *
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/
194 Disallow: /xwiki/bin/edit/
195 Disallow: /xwiki/bin/export/
196 Disallow: /xwiki/bin/get/
197 Disallow: /xwiki/bin/inline/
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/
204 Disallow: /xwiki/bin/preview/
205 Disallow: /xwiki/bin/propadd/
206 Disallow: /xwiki/bin/propdelete/
207 Disallow: /xwiki/bin/propupdate/
208 Disallow: /xwiki/bin/register/
209 Disallow: /xwiki/bin/save/
210 Disallow: /xwiki/bin/skin/
211 Disallow: /xwiki/bin/status/
212 Disallow: /xwiki/bin/upload/
213 Disallow: /xwiki/bin/viewattachrev/
214 Disallow: /xwiki/bin/viewrev/
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
222 {{/code}}
223
224
225 **Note:**
226
227 For Tomcat6 the placement of the ##robots.txt## file should be within the //$TOMCAT/webapps/ROOT// folder and should have permission 644 applied.
228
229 {{code}}
230 -rw-r--r-- 1 root www 1478 Jan 8 15:52 robots.txt
231 {{/code}}
232
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]].
234
235 = Statistics =
236
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}}
240
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.
242
243 = Monitoring =
244
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"}}
248 xwiki.monitor=0
249 {{/code}}
250
251 = Document Cache =
252
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.
254
255 {{code language="none"}}
256 xwiki.store.cache.capacity=1000
257 {{/code}}
258
259 = Cache Macro =
260
261 It's possible to perform selective content caching by using the [[Cache Macro>>extensions:Extension.Cache Macro]].
262
263 = LESS Cache =
264
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.
266
267 = Rendering cache =
268
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
271 == Configuration based ==
272
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:
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
299 You can force a page to refresh using ##refresh=1## in the URL.
300
301 Since 6.2 it's also possible to programmatically refresh any document cache using ##com.xpn.xwiki.internal.cache.rendering.RenderingCache## component:
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
313 == Enabled using velocity in document content itself (XWiki 1.0 syntax only) ==
314
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:
316
317 {{code language="none"}}
318 $context.setCacheDuration(60)
319 {{/code}}
320
321 Since 1.5M2, you can set the default rendering cache duration for all pages in ##xwiki.cfg##:
322
323 {{code language="none"}}
324 ## cache all rendered documents for one hour
325 xwiki.rendering.defaultCacheDuration=3600
326 {{/code}}
327
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
330 = Merge the CSS files =
331
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]].
333
334 = Set up NginX =
335
336 If you experience //__heavy loads__// on your wiki, you could try using NginX.
337
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).
339
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".
341
342 For more info on setting up NginX check [[this guide>>NginX]].
343
344 = Backlinks =
345
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"}}
349 xwiki.backlinks=0
350 {{/code}}
351
352 = Versioning =
353
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##:
355
356 {{code language="none"}}
357 xwiki.store.versioning=0
358 {{/code}}
359
360 = Custom Mapping =
361
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]].
363
364 = Wiki syntax features for XWiki Syntax 1.0 =
365
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.
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#HDebugmode]].

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