svn commit: r1387126 - /subversion/site/publish/docs/release-notes/1.8.html

[st...@apache.org]

Author: stsp
Date: Tue Sep 18 13:08:16 2012
New Revision: 1387126

URL: http://svn.apache.org/viewvc?rev=1387126&view=rev
Log:
* publish/docs/release-notes/1.8.html: Document incremental hotcopy.

Modified:
    subversion/site/publish/docs/release-notes/1.8.html

Modified: subversion/site/publish/docs/release-notes/1.8.html
URL: http://svn.apache.org/viewvc/subversion/site/publish/docs/release-notes/1.8.html?rev=1387126&r1=1387125&r2=1387126&view=diff
==============================================================================
--- subversion/site/publish/docs/release-notes/1.8.html (original)
+++ subversion/site/publish/docs/release-notes/1.8.html Tue Sep 18 13:08:16 2012
@@ -38,6 +38,8 @@ describes what is planned for the releas
       >Improved support for automatic merging</a></li>
   <li><a href="#neon-deleted"
       >HTTP client support based on neon has been removed</a></li>
+  <li><a href="#incremental-hotcopy"
+      >Incremental hotcopy for FSFS repositories</a></li>
   <li><a href="#gpg-agent"
       >In-memory password caching via GnuPG (<em>Unix client</em>)</a></li>
   <li><a href="#enhancements"
@@ -123,6 +125,12 @@ and what impact these changes may have.<
       might be required for optimal performance with 1.8 clients which
       access the repository via HTTP.</td></tr>
   <tr>
+    <td><a href="#incremental-hotcopy">incremental hotcopy</a></td>
+    <td>any</td>
+    <td>1.8</td>
+    <td>any</td>
+    <td></td></tr>
+  <tr>
     <td><a href="#mod-dav-svn-utf8">UTF-8 support in mod_dav_svn</a></td>
     <td>any</td>
     <td>1.8</td>
@@ -372,6 +380,49 @@ directories specially. Behavioural chang
 
 </div>  <!-- moves -->
 
+<div class="h3" id="incremental-hotcopy">
+<h3>'svnadmin hotcopy' can now operate incrementally (FSFS only)
+  <a class="sectionlink" href="#incremental-hotcopy"
+    title="Link to this section">&para;</a>
+</h3>
+
+<p>The <tt>svnadmin hotcopy</tt> command now supports incremental
+operation, triggered by the new <tt>--incremental</tt> option.</p>
+
+<p>In prior releases of Subversion, <tt>svnadmin hotcopy</tt> refused
+to copy over an existing destination repository, and always copied
+the entire repository. For large repositories, performing a hotcopy
+could take several hours, preventing an efficient backup process.</p>
+
+<p>In incremental hotcopy mode, revision data which has already been
+copied from the source to the destination repository will not be
+copied again. <tt>svnadmin hotcopy --incremental</tt> will only copy
+new revisions, and revisions which have changed in size or had their
+modification timestamp changed since the previous hotcopy operation.</p>
+
+<p>Up to now, <tt>svnsync</tt> or <tt>svnadmin dump --incremental</tt>
+were the only alternatives for incremental repository backup. However,
+these commands need to perform additional processing while transforming
+revision data into an intermediate format before creating revision
+files in the destination repository. Performance of <tt>svnadmin
+hotcopy</tt> is only limited by disk I/O.</p>
+
+<p>Incremental hotcopy is not supported for BDB repositories.
+See <a href="http://subversion.tigris.org/issues/show_bug.cgi?id=4081"
+>issue 4081</a> for more information.</p>
+
+<div class="notice">
+<p>Using general-purpose incremental backup tools, such as
+<a href="http://rsync.samba.org">rsync</a>, with Subversion repositories
+is dangerous if the repository can receive commits while the backup
+tool is running. The resulting copy might end up being corrupt because
+general-purpose backup tools do not know anything about consistency
+requirements of Subversion repositories. It is recommended to use
+incremental hotcopy instead. Alternatively, if network support is
+required for the backup procedure, <tt>svnsync</tt> should be used.</p>
+</div>
+
+</div>  <!-- incremental-hotcopy -->
 
 <div class="h3" id="gpg-agent">
 <h3>In-memory password caching via GnuPG (<em>Unix client</em>)