[svnbook commit] r1791 - trunk/src/en/book
cmpilato
svnbook-dev at red-bean.com
Fri Nov 4 09:35:57 CST 2005
Author: cmpilato
Date: Fri Nov 4 09:35:55 2005
New Revision: 1791
Modified:
trunk/src/en/book/ch09.xml
Log:
* src/en/book/ch09.xml
Clarify the differences between --incremental and --deltas by better
explaining both of them. Suggested by Seth Arnold <seth.arnold at suse.de>
Modified: trunk/src/en/book/ch09.xml
==============================================================================
--- trunk/src/en/book/ch09.xml (original)
+++ trunk/src/en/book/ch09.xml Fri Nov 4 09:35:55 2005
@@ -4363,20 +4363,45 @@
revision tree. See <xref linkend="svn.reposadmin.maint.migrate"/>
for a practical use.</para>
- <para>If the size of your Subversion dumpfile is a concern,
- you can use the <option>--deltas</option> switch to (in
- some cases drastically) reduce the size of the dumpfile
- that <command>svnadmin</command> creates. With this
- switch, instead of writing the full content of each
- revision to the dumpfile, <command>svnadmin dump</command>
- will only emit the differences from one revision to the
- next. There are, however, disadvantages to creating
- deltified dumpfiles—it's more CPU intensive to
- create them, <command>svndumpfilter</command> can't
- operate on them, and non-deltified dumpfiles tend to
- compress better.</para>
+ <para>By default, the Subversion dumpfile stream contains a
+ single revision (the first revision in the requested
+ revision range) in which every file and directory in the
+ repository in that revision is presented as if that whole
+ tree was added at once, followed by other revisions (the
+ remainder of the revisions in the requested range) which
+ contain only the files and directories which were modified
+ in those revisions. For a modified file, the complete
+ fulltext representation of its contents, as well as all of
+ its properties, are presented in the dumpfile; for a
+ directory, all of its properties are presented.</para>
+
+ <para>There are a pair of useful options which modify the
+ dumpfile generator's behavior. The first is the
+ <option>--incremental</option> option, which simply causes
+ that first revision in the dumpfile stream to contain only
+ the files and directories modified in that revision,
+ instead of being presented as the addition of a new tree,
+ and in exactly the same way that every other revision in
+ the dumpfile is presented. This is useful for generating
+ a dumpfile that is to be loaded into another repository
+ which already has the files and directories that exist in
+ the original repository.</para>
+
+ <para>The second useful option is <option>--deltas</option>.
+ This switch causes <command>svnadmin dump</command> to,
+ instead of emitting fulltext representations of file
+ contents and property lists, emit only deltas of those
+ items against their previous versions. This reduces (in
+ some cases, drastically) the size of the dumpfile that
+ <command>svnadmin</command> creates. There are, however,
+ disadvantages to using this option—deltified
+ dumpfiles are more CPU intensive to create, cannot be
+ operated on by <command>svndumpfilter</command>, and tend
+ not to compress as well as their non-deltified couterparts
+ when using third-party tools like <command>gzip</command>
+ and <command>bzip2</command>.</para>
- </refsect1>
+ </refsect1>
<refsect1>
<title>Switches</title>
More information about the svnbook-dev
mailing list