Apache Subversion 1.6 is a superset of all previous Subversion releases, and is as of the time of its release considered the current "best" release. Any feature or bugfix in 1.0.x through 1.5.x is also in 1.6, but 1.6 contains features and bugfixes not present in any earlier release. The new features will eventually be documented in a 1.6 version of the free Subversion book (svnbook.red-bean.com).
This page describes only major changes. For a complete list of changes, see the 1.6 section of the CHANGES file.
Older clients and servers interoperate transparently with 1.6 servers and clients. However, some of the new 1.6 features may not be available unless both client and server are the latest version. There are also cases where a new feature will work but will run less efficiently if the client is new and the server old.
There is no need to dump and reload your repositories. Subversion 1.6 can read repositories created by earlier versions. To upgrade an existing installation, just install the newest libraries and binaries on top of the older ones.
Subversion 1.6 maintains API/ABI compatibility with earlier releases, by only adding new functions, never removing old ones. A program written to the 1.0, 1.1, 1.2, 1.3, 1.4 or 1.5 API can both compile and run using 1.6 libraries. However, a program written for 1.6 cannot necessarily compile or run against older libraries.
| New Feature | Minimum Client1 | Minimum Server | Minimum Repository | Notes |
|---|---|---|---|---|
| FSFS Packing | any | 1.6 | 1.6 | |
| Tree Conflicts | 1.6 | 1.6 | any | Using servers older than 1.6 is possible, but some kinds of conflicts will not be detected. |
1Reminder: when using the file://
repository access method, the Subversion program is both the client
and the server. | ||||
The working copy format has been upgraded. This means that 1.5 and older Subversion clients will not be able to work with working copies produced by Subversion 1.6. Working copies are upgraded automatically.
Similarly, the repository filesystem formats have changed, meaning that 1.5 and older versions of Subversion tools that normally access a repository directly (e.g. svnserve, mod_dav_svn, svnadmin) won't be able to read a repository created by Subversion 1.6. But, repositories are not upgraded automatically.
WARNING: if a Subversion 1.6 client encounters a pre-1.6 working copy, it will automatically upgrade the working copy format as soon as it touches it, making it unreadable by older Subversion clients. If you are using several versions of Subversion on your machine, be careful about which version you use in which working copy, to avoid accidentally upgrading a working copy. (But note that this "auto upgrade" behavior does not occur with the repositories, only working copies.)
If you accidentally upgrade a 1.5 working copy to 1.6, and wish to
downgrade back to 1.5, use the change-svn-wc-format.py script. See this FAQ entry for details, and run the script with the
--help option for usage instructions.
The Subversion 1.6 server works with 1.5 and older repositories,
and it will not upgrade such repositories to 1.6 unless
specifically requested to via the
svnadmin upgrade command. This means
that some of the new 1.6 features will not become available simply by
upgrading your server: you will also have to upgrade your
repositories. (We decided not to auto-upgrade repositories because we
didn't want 1.6 to silently make repositories unusable by
1.5 — that step should be a conscious decision on the
part of the repository admin.)
Although we try hard to keep output from the command line programs compatible between releases, new information sometimes has to be added. This can break scripts that rely on the exact format of the output.
svn proplist --verbose
¶
The output of svn proplist --verbose has been
improved, and svn propget now accepts the --verbose
option. The following example illustrates these changes.
$ svn proplist --verbose build.conf
Properties on 'build.conf':
svn:eol-style
native
svn:mergeinfo
/trunk/build.conf:1-4800
/branches/a/build.conf:3000-3400
/branches/b/build.conf:3200-3600
$
svn status
¶
The output of svn status contains the additional seventh
column which informs whether the item is the victim of a tree conflict.
An additional line with more detailed description of a tree conflict is
displayed after each item remaining in tree conflict.
$ svn status
M Makefile.in
A C src/error.c
> local add, incoming add upon update
M src/log.c
M C src/path.c
> local edit, incoming delete upon update
D C src/properties.c
> local delete, incoming edit upon merge
M C src/time.c
$
svn update and
svn merge
¶
svn update and svn merge now print
a summary of conflicts upon completion.
$ svn update --accept=postpone C alpha C beta C gamma Updated to revision 3. Summary of conflicts: Text conflicts: 1 Property conflicts: 1 Tree conflicts: 1Minor problems with the conflict summary are described in issue 3342.
This section is currently incomplete, please help write it! See the design notes for more information.
$ svn SUBCOMMAND ^/ $ svn SUBCOMMAND ^/PATH
Subversion 1.6 adds a couple of new features for users of svn:externals. The include:
If the URL in a svn:externals description refers to a file, it will be added into the working copy as a versioned item.
There are a few differences between directory and file externals.
The differences between a normal versioned file and a file external.
Other facts.
Need to document possible incompatibilities (see this thread )
See The svn:externals section of the Subversion Book.
Subversion 1.6 recognizes a new kind of conflict, known as a "tree conflict". Such conflicts manifest at the level of directory structure, rather than file content.
Situations now flagged as conflicts include deletions of locally modified files, and incoming edits to locally deleted files. Files and directories which are victims of a tree conflict cannot be committed before the conflict is marked resolved.
Note that Subversion is still treating renames as a "copy+delete" operation, so file renames causing tree conflicts can only be detected in terms of file additions and deletions. Because of this, false positives during tree conflict detection are possible.
To facilitate tree conflict detection, attempting to commit the deletion of a file which has already been deleted in the HEAD revision now causes an error. In Subversion 1.5, this was treated as a no-op, potentially resulting in "empty" revisions which contained no changes.
See the tree conflicts section of the Subversion Book.
Subversion 1.6 contains several improvements to both the Berkeley DB and FSFS backends. These are designed to improve storage space, and can result in drastically smaller repositories. These changes include:
When using many branches and merging between them often, it is common to have files with similar lines of history which contain the exact same content. In the past, Subversion has stored these files as deltas against previous versions of the file. Subversion 1.6 will now use existing representations in the filesystem for duplicate storage. Depending on the size of the repository, and the degree of branching and merging, this can cause an up to 20% space reduction for Berkeley DB repositories and a 15% reduction for FSFS repositories.
Subversion 1.5 introduced the ability for FSFS repositories to be sharded into multiple directories for revision and revprop files. Subversion 1.6 takes the sharding concept further, and allows full shard directories to be packed into a single file. By reducing internal fragmentation in the filesystem, packed FSFS repositories have significant space savings over their unpacked counterparts, especially repositories which contain many small commits. Using a one-file-per-shard approach also allows Subversion to reduce disk I/O and better exploit operating system caches.
To pack a repository, run svnadmin pack on the repository.
Once a repository has been packed, there is no migration path back to an
unpacked state, and it can only be read by Subversion 1.6 or greater
servers.
Memcached can cache data of FSFS repositories.
Additional build-time dependencies: APR-Util ≥1.3 || ( APR-Util < 1.3 && APR_Memcache )
Newly created BDB repositories now use forward deltas instead of reverse
deltas. svnadmin upgrade can be used to make older repositories
use forward deltas for new revisions. If you want to achieve the most
optimized state of an older repository, you still need to perform dump and
load of the repository.
Subversion 1.6 introduces a new python binding for the Subversion API. The new binding makes use of the ctypes library to present the standard API along with a selection of Python classes to give an object-oriented interface to standard Subversion constructs. These bindings have several advantages over the traditional SWIG-based bindings:
Building the ctypes bindings produces two ways to access Subversion from python. The first interface is a direct python port of the standard API. Ctypes provides some basic type conversions and allows the calling of Subversion functions just like in C code. The new bindings also introduce a set of python classes to enable higher-level access to Subversion features. These classes take full advantage of python features and hide as much of the C implementation as possible to make Subversion easier to use for python programmers not familiar with the C API.
Interactive conflict resolution supports new display-conflict,
mine-conflict and theirs-conflict options.
Here's an example using the command-line client:
$ svn up
U Makefile.in
Conflict discovered in 'configure.ac'.
Select: (p) postpone, (df) diff-full, (e) edit,
(mc) mine-conflict, (tc) theirs-conflict,
(s) show all options: s
(e) edit - change merged file in an editor
(df) diff-full - show all changes made to merged file
(r) resolved - accept merged version of file
(dc) display-conflict - show all conflicts (ignoring merged version)
(mc) mine-conflict - accept my version for all conflicts (same)
(tc) theirs-conflict - accept their version for all conflicts (same)
(mf) mine-full - accept my version of entire file (even non-conflicts)
(tf) theirs-full - accept their version of entire file (same)
(p) postpone - mark the conflict to be resolved later
(l) launch - launch external tool to resolve conflict
(s) show all - show this list
Select: (p) postpone, (df) diff-full, (e) edit,
(mc) mine-conflict, (tc) theirs-conflict,
(s) show all options: mc
G configure.ac
Updated to revision 36666.
$
In Subversion 1.6, the --set-depth parameter to svn
update has grown a new value—exclude. This value tells
Subversion to exclude the target from the working copy, immediately and until
further notice. Prior to Subversion 1.6, if a directory could not easily be
removed from a working copy. If it was deleted without the help of Subversion,
it would return on the next svn update. If it was deleted with
svn delete, the directory remained as a local modification
forever. (Unless, of course, it was accidentally committed.) The new exclusion
mechanism in Subversion 1.6 fixes both these problems.
Note that if you exclude a versioned directory that has some unversioned files in it, or some files with local modifications, Subversion handles this situation gracefully. All the files that aren't safe to delete, Subversion leaves around, and of course leaves any intermediate directories required to reach those files, too.
svnserve now accepts the --log-file option which
allows to specify the file used for logging.
mod_dav_svn now supports a new public URI syntax for examining older versions of files or directories. The intent here is to allow users to examine history without the use of an svn client, and to make it easier for 3rd-party tools (e.g. code-review services) to work directly against repositories without using svn libraries.
http://host/repos/path?[p=PEG][&r=REV]
The new syntax works similarly to the way URIs work with the svn commandline client. Simply requesting http://host/repos/path fetches "path" in the HEAD revision. Adding a "p" query argument specifies a different peg revision instead, so that:
http://host/repos/path?p=38
...is similar to specifying "path@38" on the commandline. Adding a "r" query argument is like specifying "-r" on the commandline, causing the repository to follow history backwards from the peg revision to the older operative revision:
http://host/repos/path?p=38&r=20
As with the commandline, the peg revision defaults to HEAD if unspecified, and the operative revision defaults to the peg revision. The online Subversion Book has a section explaining peg and operative revisions in great detail.
There are far too many enhancements and new options to the command-line client to list them all here. Aside from all the ones mentioned already in these release notes, below are a few more that we consider important, but please see the 1.6.0 section in the CHANGES file for a complete list.
The svn log command can now take multiple revision arguments
in one invocation. Both the -c and -r arguments are supported.
$ svn log -r36169 -r36171 http://svn.collab.net/repos/svn/ ------------------------------------------------------------------------ r36169 | sussman | 2009-02-26 14:46:44 -0800 (Thu, 26 Feb 2009) | 1 line ...log message omitted... ------------------------------------------------------------------------ r36171 | joeswatosh | 2009-02-26 22:05:28 -0800 (Thu, 26 Feb 2009) | 20 lines ...log message omitted... $ svn log -c36169,36171 http://svn.collab.net/repos/svn/ ------------------------------------------------------------------------ r36169 | sussman | 2009-02-26 14:46:44 -0800 (Thu, 26 Feb 2009) | 1 line ...log message omitted... ------------------------------------------------------------------------ r36171 | joeswatosh | 2009-02-26 22:05:28 -0800 (Thu, 26 Feb 2009) | 20 lines ...log message omitted...
Option added to svn and svnsync, so that
non-interactive operations can work with self-signed certificates not
backed by a known trust authority.
$ svn log -r36364 https://svn.collab.net/repos/svn/trunk --trust-server-cert --non-interactive ------------------------------------------------------------------------ r36364 | stylesen | 2009-03-06 13:11:20 +0530 (Fri, 06 Mar 2009) | 3 lines ...log message omitted... ------------------------------------------------------------------------without this option:
$ svn log -r36364 https://svn.collab.net/repos/svn/trunk
Error validating server certificate for 'https://svn.collab.net':
- The certificate is not issued by a trusted authority. Use the
fingerprint to validate the certificate manually!
Certificate information:
- Hostname: svn.collab.net
- Valid: from Sep 24 22:01:07 2007 GMT until Sep 23 22:01:07 2011 GMT
- Issuer: sv, CollabNet, Brisbane, California, US
(hostname@collab.net)
- Fingerprint:
AA:5B:74:B1:E2:7F:38:B3:2B:C2:B1:60:6E:01:BB:F5:7C:37:98:46
(R)eject, accept (t)emporarily or accept (p)ermanently? t
------------------------------------------------------------------------
r36364 | stylesen | 2009-03-06 13:11:20 +0530 (Fri, 06 Mar 2009) | 3 lines
...log message omitted...
------------------------------------------------------------------------
The pre-lock hook can now specify the lock-token string via the hook's stdout; see r872852 for details. Note that when the hook uses this feature, it must take responsibility for ensuring that lock tokens are unique across the repository.
There are too many new and revised APIs in Subversion 1.6.0 to list them all here. See the Subversion API Documentation page for general API information. If you develop a 3rd-party client application that uses Subversion APIs, you should probably look at the header files for the interfaces you use and see what's changed.
One general change is that most APIs that formerly took a recurse parameter have been upgraded to accept a depth parameter instead, to enable the new sparse checkouts feature.
Language bindings have mostly been updated for the new APIs, though some may lag more than others.
Building Subversion 1.6.20, or earlier, with GCC 4.7 will fail to compile when configured to include KDE wallet support. This can be fixed by configuring without KDE wallet support, or by building with an older GCC, or by patching with r1345740 from trunk. A fix is likely to be included in any future 1.6.x release.
There are known testsuite fails that occur intermittently:
The Subversion 1.4.x line is no longer supported. This doesn't mean that your 1.4 installation is doomed; if it works well and is all you need, that's fine. "No longer supported" just means we've stopped accepting bug reports against 1.4.x versions, and will not make any more 1.4.x bugfix releases.
We now require SQLite to build both
the server and client. We recommend 3.6.13 or greater, but work with
anything better than 3.4.0. Subversion will attempt to use an SQLite
amalgamation if it is
present in the root of the distribution tarball, otherwise, Subversion will
search for SQLite in the usual places on the system. You may also pass
--with-sqlite to configure to specify the location
of the SQLite library or amalgamation you wish to use.