svn commit: r1043669 - /subversion/site/publish/docs/release-notes/1.7.html

[hw...@apache.org]

Author: hwright
Date: Wed Dec  8 20:50:48 2010
New Revision: 1043669

URL: http://svn.apache.org/viewvc?rev=1043669&view=rev
Log:
* publish/docs/release-notes/1.7.html
  (wc-ng): Add some text and subpoints about wc-ng.

Modified:
    subversion/site/publish/docs/release-notes/1.7.html

Modified: subversion/site/publish/docs/release-notes/1.7.html
URL: http://svn.apache.org/viewvc/subversion/site/publish/docs/release-notes/1.7.html?rev=1043669&r1=1043668&r2=1043669&view=diff
==============================================================================
--- subversion/site/publish/docs/release-notes/1.7.html (original)
+++ subversion/site/publish/docs/release-notes/1.7.html Wed Dec  8 20:50:48 2010
@@ -172,7 +172,75 @@ example illustrates these changes.</p>
     title="Link to this section">&para;</a>
 </h3>
 
-<p>Wherein we describe all the magic behind wc-ng.</p>
+<p>Subversion 1.7 features a complete re-write of the working copy
+metadata management system of Subversion, code named WC-NG.  The old system
+was one of the first parts of Subversion written, and over time had grown
+difficult to maintain and extend.  WC-NG is intended to provide an
+immediate performance improvement, while also enable many future feature 
+enhancements.</p>
+
+<p>Although Subversion 1.7 does not introduce these new features, the
+improvements in the working copy storage make them much more likely to
+appear in future releases.</p>
+
+<div class="h4" id="single-db"> 
+<h4>Centralized Metadata Storage
+  <a class="sectionlink" href="#single-db"
+    title="Link to this section">&para;</a> 
+</h4>
+
+<p>A key feature of the changes introduced in Subversion 1.7 is the
+centralization of worky copy metadata storage into a single location.
+Instead of a <code>.svn</code> directory in every directory in the working
+copy, Subversion 1.7 working copies have just one <code>.svn</code>
+directory&mdash;in the root of the working copy.  This directory includes
+(among other things) an SQLite-backed database which contains all of the
+metadata Subversion needs for that working copy.</p>
+
+<p>Even though the data is stored in a structured format, the relationships
+between the data are complex.  We highly discourage external tools from
+modifying the data held in this database, as such modification is likely to
+result in working copy corruption.</p>
+
+</div>  <!-- single-db -->
+
+<div class="h4" id="wc-pristines"> 
+<h4>Upgrading the Working Copy
+  <a class="sectionlink" href="#wc-prinstines"
+    title="Link to this section">&para;</a> 
+</h4>
+
+<p>Subversion keeps a record of the unmodified contents of all files in the
+working copy.  Historically, these have been called <em>text-bases</em>, but
+in Subversion 1.7, they have received a new name, and a new home.  With the
+centralization of metadata, the text-bases have been renamed
+<em>pristines</em>, and are now located in the same <code>.svn</code>
+directory as the working copy metadata.</p>
+
+<p>The pristines are stored by checksum in a sharded format.  Any files
+in the working copy which have the same pristine content will now share
+references to the pristine store, making such working copies slightly
+smaller.  Running <code>svn cleanup</code> will remove any pristines which
+are no longer needed by the current state of the working copy.</p>
+
+</div>
+
+<div class="h4" id="wc-upgrade"> 
+<h4>Upgrading the Working Copy
+  <a class="sectionlink" href="#wc-upgrade"
+    title="Link to this section">&para;</a> 
+</h4>
+
+<p>Subversion 1.7 introduces substantial changes to the working copy format.
+In previous releases of Subversion, Subversion would automatically update
+the working copy to the new format when a write operation was performed.
+Subversion 1.7, however, will make this a manual step.  Before using
+Subversion 1.7 with their working copies, users will be required
+to run a new command, <code>svn upgrade</code> to update the metadata to the
+new format.  This command may take a while, and for some users, it may be more
+practical to simply checkout a new working copy.</p>
+
+</div>  <!-- wc-upgrade -->
 
 </div>  <!-- wc-ng -->