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Posted to commits@jackrabbit.apache.org by th...@apache.org on 2015/02/25 17:45:31 UTC
svn commit: r1662256 - in /jackrabbit/site/live/oak/docs: .DS_Store FAQ.html
nodestore/persistent-cache.html
Author: thomasm
Date: Wed Feb 25 16:45:31 2015
New Revision: 1662256
URL: http://svn.apache.org/r1662256
Log:
OAK-936: Site checkin for project Oak Documentation-1.1-SNAPSHOT
Added:
jackrabbit/site/live/oak/docs/.DS_Store (with props)
Modified:
jackrabbit/site/live/oak/docs/FAQ.html
jackrabbit/site/live/oak/docs/nodestore/persistent-cache.html
Added: jackrabbit/site/live/oak/docs/.DS_Store
URL: http://svn.apache.org/viewvc/jackrabbit/site/live/oak/docs/.DS_Store?rev=1662256&view=auto
==============================================================================
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Propchange: jackrabbit/site/live/oak/docs/.DS_Store
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svn:mime-type = application/octet-stream
Modified: jackrabbit/site/live/oak/docs/FAQ.html
URL: http://svn.apache.org/viewvc/jackrabbit/site/live/oak/docs/FAQ.html?rev=1662256&r1=1662255&r2=1662256&view=diff
==============================================================================
--- jackrabbit/site/live/oak/docs/FAQ.html (original)
+++ jackrabbit/site/live/oak/docs/FAQ.html Wed Feb 25 16:45:31 2015
@@ -442,7 +442,7 @@
<p>You might be missing an index. See <a href="query.html">Query engine</a>.</p></div>
<div class="section">
<h4>I get a warning “Attempt to perform … while another thread is concurrently …”, what is wrong?<a name="I_get_a_warning_Attempt_to_perform__while_another_thread_is_concurrently__what_is_wrong"></a></h4>
-<p>You are accessing a <tt>Session</tt> instance concurrently from multiple threads. Session instances are <a href="dos_and_donts.html#Anti_pattern:_concurrent_session_access">not thread safe</a>.</p></div>
+<p>You are accessing a <tt>Session</tt> instance concurrently from multiple threads. Session instances are <a href="dos_and_donts.html#Anti_pattern:_concurrent_session_access">not thread safe</a>. Enabling <tt>DEBUG</tt> logging for <tt>SessionDelegate</tt> provides stack traces for both sessions involved. <i>Note</i>: this should be used for debugging only as it has a major impact on system performance.</p></div>
<div class="section">
<h4>I have a SegmentMK store and the size is growing beyond control<a name="I_have_a_SegmentMK_store_and_the_size_is_growing_beyond_control"></a></h4>
<p>You need to setup a regular job for <a href="nodestore/segmentmk.html#Segment_Compaction">compacting the segments</a>.</p></div>
Modified: jackrabbit/site/live/oak/docs/nodestore/persistent-cache.html
URL: http://svn.apache.org/viewvc/jackrabbit/site/live/oak/docs/nodestore/persistent-cache.html?rev=1662256&r1=1662255&r2=1662256&view=diff
==============================================================================
--- jackrabbit/site/live/oak/docs/nodestore/persistent-cache.html (original)
+++ jackrabbit/site/live/oak/docs/nodestore/persistent-cache.html Wed Feb 25 16:45:31 2015
@@ -0,0 +1,526 @@
+<!DOCTYPE html>
+<!--
+ | Generated by Apache Maven Doxia at 2015-02-25
+ | Rendered using Apache Maven Fluido Skin 1.3.0
+-->
+<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+ <head>
+ <meta charset="UTF-8" />
+ <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+ <meta name="Date-Revision-yyyymmdd" content="20150225" />
+ <meta http-equiv="Content-Language" content="en" />
+ <title>Jackrabbit Oak - Persistent Cache</title>
+ <link rel="stylesheet" href="../css/apache-maven-fluido-1.3.0.min.css" />
+ <link rel="stylesheet" href="../css/site.css" />
+ <link rel="stylesheet" href="../css/print.css" media="print" />
+
+
+ <script type="text/javascript" src="../js/apache-maven-fluido-1.3.0.min.js"></script>
+
+
+ </head>
+ <body class="topBarEnabled">
+
+
+
+
+
+
+ <a href="http://github.com/apache/jackrabbit-oak">
+ <img style="position: absolute; top: 0; right: 0; border: 0; z-index: 10000;"
+ src="https://s3.amazonaws.com/github/ribbons/forkme_right_red_aa0000.png"
+ alt="Fork me on GitHub">
+ </a>
+
+
+
+
+
+ <div id="topbar" class="navbar navbar-fixed-top ">
+ <div class="navbar-inner">
+ <div class="container-fluid">
+ <a data-target=".nav-collapse" data-toggle="collapse" class="btn btn-navbar">
+ <span class="icon-bar"></span>
+ <span class="icon-bar"></span>
+ <span class="icon-bar"></span>
+ </a>
+
+ <a class="brand" href="../" title="Oak logo">
+
+
+ <img src="../oak_logo.png" alt="Oak logo" />
+
+ </a>
+
+ <ul class="nav">
+ <li class="dropdown">
+ <a href="#" class="dropdown-toggle" data-toggle="dropdown">Overview <b class="caret"></b></a>
+ <ul class="dropdown-menu">
+
+ <li> <a href="../index.html" title="Jackrabbit Oak">Jackrabbit Oak</a>
+</li>
+
+ <li> <a href="../license.html" title="License">License</a>
+</li>
+
+ <li> <a href="../downloads.html" title="Downloads">Downloads</a>
+</li>
+ </ul>
+ </li>
+ <li class="dropdown">
+ <a href="#" class="dropdown-toggle" data-toggle="dropdown">Concepts and Architecture <b class="caret"></b></a>
+ <ul class="dropdown-menu">
+
+ <li> <a href="../architecture/overview.html" title="Overview">Overview</a>
+</li>
+
+ <li> <a href="../architecture/nodestate.html" title="The Node State Model">The Node State Model</a>
+</li>
+ </ul>
+ </li>
+ <li class="dropdown">
+ <a href="#" class="dropdown-toggle" data-toggle="dropdown">Main APIs <b class="caret"></b></a>
+ <ul class="dropdown-menu">
+
+ <li> <a href="http://www.day.com/specs/jcr/2.0/index.html" title="JCR API">JCR API</a>
+</li>
+
+ <li> <a href="../oak_api/overview.html" title="Oak API">Oak API</a>
+</li>
+ </ul>
+ </li>
+ <li class="dropdown">
+ <a href="#" class="dropdown-toggle" data-toggle="dropdown">Features and Plugins <b class="caret"></b></a>
+ <ul class="dropdown-menu">
+
+ <li> <a href="../nodestore/overview.html" title="Node Storage">Node Storage</a>
+</li>
+
+ <li> <a href="../plugins/blobstore.html" title="Blob Storage">Blob Storage</a>
+</li>
+
+ <li> <a href="../query/query.html" title="Query">Query</a>
+</li>
+
+ <li> <a href="../security/overview.html" title="Security">Security</a>
+</li>
+
+ <li> <a href="../clustering.html" title="Clustering">Clustering</a>
+</li>
+ </ul>
+ </li>
+ <li class="dropdown">
+ <a href="#" class="dropdown-toggle" data-toggle="dropdown">Using Oak <b class="caret"></b></a>
+ <ul class="dropdown-menu">
+
+ <li> <a href="../use_getting_started.html" title="Getting Started">Getting Started</a>
+</li>
+
+ <li> <a href="../construct.html" title="Repository Construction">Repository Construction</a>
+</li>
+
+ <li> <a href="../osgi_config.html" title="Configuring Oak">Configuring Oak</a>
+</li>
+
+ <li> <a href="../command_line.html" title="Command Line Tools">Command Line Tools</a>
+</li>
+
+ <li> <a href="../differences.html" title="Differences to Jackrabbit 2">Differences to Jackrabbit 2</a>
+</li>
+
+ <li> <a href="../known_issues.html" title="Known Issues">Known Issues</a>
+</li>
+
+ <li> <a href="../dos_and_donts.html" title="Dos and Don'ts">Dos and Don'ts</a>
+</li>
+
+ <li> <a href="../coldstandby/coldstandby.html" title="Cold Standby">Cold Standby</a>
+</li>
+
+ <li> <a href="../FAQ.html" title="FAQ">FAQ</a>
+</li>
+ </ul>
+ </li>
+ <li class="dropdown">
+ <a href="#" class="dropdown-toggle" data-toggle="dropdown">Developing Oak <b class="caret"></b></a>
+ <ul class="dropdown-menu">
+
+ <li> <a href="../dev_getting_started.html" title="Getting Started">Getting Started</a>
+</li>
+
+ <li> <a href="../participating.html" title="Participating">Participating</a>
+</li>
+
+ <li> <a href="../apidocs/index.html" title="API Docs">API Docs</a>
+</li>
+ </ul>
+ </li>
+ <li class="dropdown">
+ <a href="#" class="dropdown-toggle" data-toggle="dropdown">Links <b class="caret"></b></a>
+ <ul class="dropdown-menu">
+
+ <li> <a href="http://jackrabbit.apache.org/oak" title="Apache Jackrabbit Oak">Apache Jackrabbit Oak</a>
+</li>
+
+ <li> <a href="http://jackrabbit.apache.org/" title="Apache Jackrabbit">Apache Jackrabbit</a>
+</li>
+ </ul>
+ </li>
+ </ul>
+
+
+
+
+ </div>
+
+ </div>
+ </div>
+ </div>
+
+ <div class="container-fluid">
+ <div id="banner">
+ <div class="pull-left">
+ <div id="bannerLeft">
+ <h2>Oak Documentation</h2>
+ </div>
+ </div>
+ <div class="pull-right"> </div>
+ <div class="clear"><hr/></div>
+ </div>
+
+ <div id="breadcrumbs">
+ <ul class="breadcrumb">
+
+
+ <li id="publishDate">Last Published: 2015-02-25</li>
+ <li class="divider">|</li> <li id="projectVersion">Version: 1.1-SNAPSHOT</li>
+
+
+
+
+ </ul>
+ </div>
+
+
+ <div class="row-fluid">
+ <div id="leftColumn" class="span3">
+ <div class="well sidebar-nav">
+
+
+ <ul class="nav nav-list">
+ <li class="nav-header">Overview</li>
+
+ <li>
+
+ <a href="../index.html" title="Jackrabbit Oak">
+ <i class="none"></i>
+ Jackrabbit Oak</a>
+ </li>
+
+ <li>
+
+ <a href="../license.html" title="License">
+ <i class="none"></i>
+ License</a>
+ </li>
+
+ <li>
+
+ <a href="../downloads.html" title="Downloads">
+ <i class="none"></i>
+ Downloads</a>
+ </li>
+ <li class="nav-header">Concepts and Architecture</li>
+
+ <li>
+
+ <a href="../architecture/overview.html" title="Overview">
+ <i class="none"></i>
+ Overview</a>
+ </li>
+
+ <li>
+
+ <a href="../architecture/nodestate.html" title="The Node State Model">
+ <i class="none"></i>
+ The Node State Model</a>
+ </li>
+ <li class="nav-header">Main APIs</li>
+
+ <li>
+
+ <a href="http://www.day.com/specs/jcr/2.0/index.html" class="externalLink" title="JCR API">
+ <i class="none"></i>
+ JCR API</a>
+ </li>
+
+ <li>
+
+ <a href="../oak_api/overview.html" title="Oak API">
+ <i class="none"></i>
+ Oak API</a>
+ </li>
+ <li class="nav-header">Features and Plugins</li>
+
+ <li>
+
+ <a href="../nodestore/overview.html" title="Node Storage">
+ <i class="none"></i>
+ Node Storage</a>
+ </li>
+
+ <li>
+
+ <a href="../plugins/blobstore.html" title="Blob Storage">
+ <i class="none"></i>
+ Blob Storage</a>
+ </li>
+
+ <li>
+
+ <a href="../query/query.html" title="Query">
+ <i class="none"></i>
+ Query</a>
+ </li>
+
+ <li>
+
+ <a href="../security/overview.html" title="Security">
+ <i class="none"></i>
+ Security</a>
+ </li>
+
+ <li>
+
+ <a href="../clustering.html" title="Clustering">
+ <i class="none"></i>
+ Clustering</a>
+ </li>
+ <li class="nav-header">Using Oak</li>
+
+ <li>
+
+ <a href="../use_getting_started.html" title="Getting Started">
+ <i class="none"></i>
+ Getting Started</a>
+ </li>
+
+ <li>
+
+ <a href="../construct.html" title="Repository Construction">
+ <i class="none"></i>
+ Repository Construction</a>
+ </li>
+
+ <li>
+
+ <a href="../osgi_config.html" title="Configuring Oak">
+ <i class="none"></i>
+ Configuring Oak</a>
+ </li>
+
+ <li>
+
+ <a href="../command_line.html" title="Command Line Tools">
+ <i class="none"></i>
+ Command Line Tools</a>
+ </li>
+
+ <li>
+
+ <a href="../differences.html" title="Differences to Jackrabbit 2">
+ <i class="none"></i>
+ Differences to Jackrabbit 2</a>
+ </li>
+
+ <li>
+
+ <a href="../known_issues.html" title="Known Issues">
+ <i class="none"></i>
+ Known Issues</a>
+ </li>
+
+ <li>
+
+ <a href="../dos_and_donts.html" title="Dos and Don'ts">
+ <i class="none"></i>
+ Dos and Don'ts</a>
+ </li>
+
+ <li>
+
+ <a href="../coldstandby/coldstandby.html" title="Cold Standby">
+ <i class="none"></i>
+ Cold Standby</a>
+ </li>
+
+ <li>
+
+ <a href="../FAQ.html" title="FAQ">
+ <i class="none"></i>
+ FAQ</a>
+ </li>
+ <li class="nav-header">Developing Oak</li>
+
+ <li>
+
+ <a href="../dev_getting_started.html" title="Getting Started">
+ <i class="none"></i>
+ Getting Started</a>
+ </li>
+
+ <li>
+
+ <a href="../participating.html" title="Participating">
+ <i class="none"></i>
+ Participating</a>
+ </li>
+
+ <li>
+
+ <a href="../apidocs/index.html" title="API Docs">
+ <i class="none"></i>
+ API Docs</a>
+ </li>
+ <li class="nav-header">Links</li>
+
+ <li>
+
+ <a href="http://jackrabbit.apache.org/oak" class="externalLink" title="Apache Jackrabbit Oak">
+ <i class="none"></i>
+ Apache Jackrabbit Oak</a>
+ </li>
+
+ <li>
+
+ <a href="http://jackrabbit.apache.org/" class="externalLink" title="Apache Jackrabbit">
+ <i class="none"></i>
+ Apache Jackrabbit</a>
+ </li>
+ </ul>
+
+
+
+ <hr class="divider" />
+
+ <div id="poweredBy">
+
+ <script type="text/javascript" src="https://apis.google.com/js/plusone.js"></script>
+
+
+ <div class="g-plusone" data-href="http://jackrabbit.apache.org/oak/docs/" data-size="tall" ></div>
+
+ <div class="clear"></div>
+ <div class="clear"></div>
+ <div class="clear"></div>
+ <a href="http://maven.apache.org/" title="Built by Maven" class="poweredBy">
+ <img class="builtBy" alt="Built by Maven" src="../images/logos/maven-feather.png" />
+ </a>
+ </div>
+ </div>
+ </div>
+
+
+ <div id="bodyColumn" class="span9" >
+
+ <!-- Licensed to the Apache Software Foundation (ASF) under one or more
+ contributor license agreements. See the NOTICE file distributed with
+ this work for additional information regarding copyright ownership.
+ The ASF licenses this file to You under the Apache License, Version 2.0
+ (the "License"); you may not use this file except in compliance with
+ the License. You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License. --><div class="section">
+<h2>Persistent Cache<a name="Persistent_Cache"></a></h2>
+<p>The document storage optionally uses the persistent cache. The cache acts like an in-memory cache for old revisions, but in addition to keeping the most recently used nodes in memory, it also stores them to disk. That way, many reads from the storage backend (for example MongoDB) are replaced by reads from the local disk. This is specially useful if reads from the local disk are faster than reads from the storage backend. In addition to that, the persistent cache reduces the load on the storage backend.</p>
+<div class="section">
+<h3> OSGi Configuration<a name="aOSGi_Configuration"></a></h3>
+<p>The OSGi configuration of the persistent cache is:</p>
+
+<div class="source">
+<pre>org.apache.jackrabbit.oak.plugins.document.DocumentNodeStoreService
+ persistentCache=./cache
+</pre></div>
+<p>This will enable the persistent cache, and set the configuration option to “./cache”.</p></div>
+<div class="section">
+<h3>Configuration Options<a name="Configuration_Options"></a></h3>
+<p>The persistent cache configuration setting is string with a number of comma separated elements. The first element is the directory where the cache is stored. Example:</p>
+
+<div class="source">
+<pre>./cache
+</pre></div>
+<p>In this case, the data is stored in the directory “cache”, relative to the current working directory. By default, there are at most two files (two generations) with the name “cache-x.data”, where x is an incrementing number (0, 1,…). A file is at most 1 GB by default. If the file is larger, the next file is created, and if there are more than two files, the oldest one is removed. If data from the older file is accessed, it is copied to the latest file. That way, data that is not recently read will eventually be removed.</p>
+<p>The following other configuration options are available:</p>
+
+<ul>
+
+<li>
+<p>Size. A file is at most 1 GB by default. To change maximum size of a file, use “size=x”, where x is the size in MB.</p></li>
+
+<li>
+<p>Binary caching. When using the BlobStore, binaries smaller than 1 MB are stored in the persistent cache by default. The maximum size can be changed using the setting “binary=x”, where x is the size in bytes. To disable the binary cache, use “binary=0”.</p></li>
+
+<li>
+<p>Node caching. By default, nodes at all revisions are cached. To disable this option, use “-nodes”.</p></li>
+
+<li>
+<p>Children caching. By default, the list of children of a node is cached. To disable this option, use “-children”.</p></li>
+
+<li>
+<p>Diff caching. By default, the list of differences between two revisions is cached. To disable this option, use “-diff”.</p></li>
+
+<li>
+<p>Compaction. By default, when a cache file is closed, it is compacted and compressed (at a rate of around 100 MB per second). That way, the disk space is used more efficiently. To disable this option, use “-compact”.</p></li>
+
+<li>
+<p>Compression. By default, the cache is compressed, saving space. To disable this option, use “-compress”.</p></li>
+</ul>
+<p>Those setting can be appended to the persistent cache configuration string. An example configuration is:</p>
+
+<div class="source">
+<pre>./cache,size=2048,binary=0,-compact,-compress
+</pre></div></div>
+<div class="section">
+<h3> Dependencies<a name="aDependencies"></a></h3>
+<p>Internally, the persistent cache uses a key-value store (basically a java.util.Map), which is persisted to disk. The current key-value store backend is the <a class="externalLink" href="http://www.h2database.com/html/mvstore.html">H2 MVStore</a>. This library is only needed if the persistent cache is configured. Version 1.4.185 or newer is needed.</p>
+
+<div class="source">
+<pre><dependency>
+ <groupId>com.h2database</groupId>
+ <artifactId>h2-mvstore</artifactId>
+ <version>1.4.185</version>
+</dependency>
+</pre></div></div></div>
+ </div>
+ </div>
+ </div>
+
+ <hr/>
+
+ <footer>
+ <div class="container-fluid">
+ <div class="row span12">Copyright © 2012-2015
+ <a href="http://www.apache.org/">The Apache Software Foundation</a>.
+ All Rights Reserved.
+
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+
+
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+
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+
+ <div id="ohloh" class="pull-right">
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