<?xml version='1.0' encoding='utf-8'?>
<?xml-stylesheet type="text/xml" href="compare-ml.xsl"?>
<!DOCTYPE comparison SYSTEM "comparison.dtd">
<!--
TODO:
* Add intelligent merging of renamed paths.
* Add IDE integration.
* Add Speed (?)
-->
<comparison>
<meta>
<implementations>
<impl id="cvs">
<name>CVS</name>
</impl>
<impl id="aegis">
<name>Aegis</name>
</impl>
<impl id="arch">
<name>Arch</name>
</impl>
<impl id="bitkeeper">
<name>BitKeeper</name>
</impl>
<impl id="cmsynergy">
<name>CMSynergy</name>
</impl>
<impl id="co-op">
<name>Co-Op</name>
</impl>
<impl id="darcs">
<name>Darcs</name>
</impl>
<impl id="monotone">
<name>Monotone</name>
</impl>
<impl id="opencm">
<name>OpenCM</name>
</impl>
<impl id="perforce">
<name>Perforce</name>
</impl>
<impl id="subversion">
<name>Subversion</name>
</impl>
<impl id="superversion">
<name>Superversion</name>
</impl>
<impl id="svk">
<name>svk</name>
</impl>
<impl id="vesta">
<name>Vesta</name>
</impl>
<impl id="vss">
<name>Visual SourceSafe</name>
</impl>
</implementations>
<timestamp>
$Id: scm-comparison.xml 61 2005-04-06 17:09:28Z shlomif $
</timestamp>
</meta>
<contents>
<section id="main">
<title>Version Control System Comparison</title>
<expl>
This is a comparison of version-control systems. It is split
into several categories and sub-categories under which the
systems are checked.
</expl>
<section id="repos_operations">
<title>Repository Operations</title>
<section id="atomic_commits">
<title>Atomic Commits</title>
<expl>
Support for atomic commits means that if an operation on the
repository is interrupted in the middle, the repository will
not be left in an inconsistant state. Are the check-in
operations atomic? Are the check-in operations atomic, or can
interrupting an operation leave the repository in an
intermediate state?
</expl>
<compare>
<s id="cvs">No. CVS commits are not atomic.</s>
<s id="arch">Yes. Commits are atomic.</s>
<s id="darcs">Yes. Commits are atomic.</s>
<s id="subversion">Commits are atomic.</s>
<s id="superversion">Commits are atomic.</s>
<s id="svk">Commits are atomic.</s>
<s id="aegis">Commits are atomic.</s>
<s id="bitkeeper">Yes (but need to verify)</s>
<s id="monotone">Yes.</s>
<s id="opencm">Yes. Commits are atomic.</s>
<s id="perforce">Yes. Commits are atomic.</s>
<s id="vesta">Yes. Commits are atomic.</s>
<s id="co-op">Yes. Commits are atomic.</s>
<s id="vss">No. VSS commits are not atomic.</s>
<s id="cmsynergy">Yes. Commits are atomic.</s>
</compare>
</section>
<section id="move">
<title>Files and Directories Moves or Renames</title>
<expl>
Does the system support moving a file or directory to
a different location while still retaining the history
of the file?
</expl>
<compare>
<s id="cvs">
No. Renames are not supported and a manual one
may break history in two.
</s>
<s id="subversion">Yes. Renames are supported.</s>
<s id="superversion">No. Renames are not supported.</s>
<s id="svk">Yes. Renames are supported.</s>
<s id="arch">Yes. Renames are supported.</s>
<s id="darcs">Yes. Renames are supported.</s>
<s id="bitkeeper">Yes. Renames are supported.</s>
<s id="aegis">Yes. Renames are supported.</s>
<s id="monotone">Yes. Renames are supported.</s>
<s id="opencm">Yes. Renames are supported</s>
<s id="perforce">
Not directly (you copy and then delete but it manages to
keep track of the branch; the item below allows for this
very feature)
</s>
<s id="vesta">
Yes. The unit of checkout/checkin is a directory
tree. Files and directories can be added,
deleted, and renamed between versions.
</s>
<s id="co-op">Renames of files are supported.
Renaming a directory requires creating a new one,
moving the files and deleting the old one.
Moved file histories are preserved.
</s>
<s id="vss">
Affects the whole history, it's like renaming a
file in the CVS repository. There is a kludgy workaround
using "share-rename,move,delete" that gets what you
want.
</s>
<s id="cmsynergy">Yes. Renames are supported.</s>
</compare>
</section>
<section id="copy">
<title>File and Directories Copies</title>
<expl>
Does the version control system supports copying
files or directories to a different location at the
repository level, while retaining the history?
</expl>
<compare>
<s id="cvs">No. Copies are not supported.</s>
<s id="subversion">Yes. And it's a very cheap operation (O(1)) that
is also utilized for branching
</s>
<s id="superversion">No. Copies are not supported.</s>
<s id="svk">Yes. Same as subversion.</s>
<s id="arch">No. Copies of files and directory structures are
not supported.
</s>
<s id="darcs">No. Copies of files and directory structures are
not supported.
</s>
<s id="bitkeeper">
Yes. Copies are supported.
</s>
<s id="aegis">No. Copies are not supported.</s>
<s id="monotone">Yes. Copies are supported</s>
<s id="opencm">No. Copies are not supported.</s>
<s id="perforce">Copies are supported (though, because
of its architecture, I don't know how well)
</s>
<s id="vesta">
Yes. A new package/branch can be based on any
existing version without affecting the past
history. (This is also an O(1) operation.)
</s>
<s id="co-op">Copying doesn't retain history, moving does.</s>
<s id="vss">Yes. Copies are supported up to a point.</s>
<s id="cmsynergy">Yes, and it's a very cheap operation (update the target
directory to include the new file/directory).
</s>
</compare>
</section>
<section id="repos_clone">
<title>Remote Repository Replication</title>
<expl>
Does the system support cloning a remote repository to get
a functionally equivalent copy in the local system? That
should be done without any special access to the remote
server except for normal repository access.
</expl>
<compare>
<s id="cvs">No.</s>
<s id="subversion">Indirectly, by using Chia-Ling Kao's SVN::Mirror
add-on or Shlomi Fish' svn-push utility.
</s>
<s id="superversion">Yes.</s>
<s id="svk">Yes.</s>
<s id="arch">Yes.</s>
<s id="darcs">Yes.</s>
<s id="bitkeeper">Yes.</s>
<s id="aegis">Yes.</s>
<s id="monotone">Yes.</s>
<s id="opencm">No.</s>
<s id="perforce">Yes. Via the Perforce Proxy (P4P) tool.</s>
<s id="vesta">Yes. Replication is a fundamental part of the design.</s>
<s id="co-op">Repositories are always replicated on local machines.
There is no central server.
</s>
<s id="vss">
Not directly possible with the included GUI or
command line tools; ssarc and ssrestor might be useable
</s>
<s id="cmsynergy">Yes, as long as you have the (more expensive) Distributed package.</s>
</compare>
</section>
<section id="push">
<title>Propagating Changes to Parent Repositories</title>
<expl>
Can the system propagate changes from one repository to
another?
</expl>
<compare>
<s id="cvs">No.</s>
<s id="subversion">Yes, using either Chia-Ling Kao's SVN::Mirror
script or the svn-push utility by Shlomi Fish.
</s>
<s id="superversion">No.</s>
<s id="svk">Yes.</s>
<s id="arch">Yes.</s>
<s id="darcs">Yes.</s>
<s id="bitkeeper">Yes.</s>
<s id="aegis">Yes.</s>
<s id="monotone">Yes.</s>
<s id="opencm">No.</s>
<s id="perforce">Unknown. Probably Not.</s>
<s id="vesta">
Yes.
</s>
<s id="co-op">It's a peer-to-peer system,
which keeps all replicas of the repository in sync.
</s>
<s id="vss">
Not directly possible with the included GUI or
command line tools; ssarc and ssrestor might be useable
</s>
<s id="cmsynergy">Yes, as long as you have the (more expensive) Distributed package.</s>
</compare>
</section>
<section id="permissions">
<title>Repository Permissions</title>
<expl>
Is it possible to define permissions on access to different
parts of a remote repository? Or is access open for all?
</expl>
<compare>
<s id="cvs">
Limited. "pre-commit hook scripts" can be used to
implement various permissions systems.
</s>
<s id="arch">
Yes. It is possible to define permissions on access to
different parts of a remote repository based on the
permission systems of the underlying protocol.
</s>
<s id="darcs">
No.
</s>
<s id="aegis">
Yes. Aegis relies on the UNIX permissions system to
implement permissions for files in the repository.
</s>
<s id="bitkeeper">
FILL IN
</s>
<s id="subversion">
Yes. The WebDAV-based service supports defining HTTP
permissions for various directories of the repository.
</s>
<s id="superversion">
No.
</s>
<s id="svk">
Same as subversion.
</s>
<s id="monotone">
Yes. It is possible to restrict incoming changes
from certain sources to be performed only in certain
parts of the repository.
</s>
<s id="opencm">
Permissions are defined on a per-branch
basis.
</s>
<s id="perforce">
Yes. (more than half a dozen of permission levels that can
be set in a file by file basis)
</s>
<s id="vesta">
Yes. Access permissions for each package (the
unit of checkout/checkin) can be different.
Access permissions for a branch can be different
from the basis package.
</s>
<s id="co-op">First access (joining the project)
requires administrator's approval.
Subsequent access to that project is not controlled.
</s>
<s id="vss">
Project specific permissions (read, write, delete, destroy)
can be set per user; but see "Networking Support":
this makes "Repository Permissions" a hindrance to
accidental damage but cannot prevent intentional damage.
</s>
<s id="cmsynergy">No, though a single server can serve many repositories.</s>
</compare>
</section>
<section id="changesets">
<title>Changesets' Support</title>
<expl>
Does the repository supports changesets? Changesets are a way
to group a number of modifications that are relevant to each
other in one atomic package, that can be cancelled or
propagated as needed.
</expl>
<compare>
<s id="cvs">No. Changes are file-specific.</s>
<s id="subversion">Partial support. There are implicit
changeset that are generated on each commit.
</s>
<s id="superversion">Partial support. Changes are grouped into changesets,
but cannot be cancelled invididually yet.
</s>
<s id="svk">Same as subversion.
</s>
<s id="aegis">
Yes. Changesets are supported.
</s>
<s id="bitkeeper">
Yes. Changesets are supported.
</s>
<s id="arch">
Yes. Changesets are supported.
</s>
<s id="darcs">
Yes. Changesets are supported.
</s>
<s id="monotone">
Yes. Changesets are supported.
</s>
<s id="opencm">
Yes. Changesets are supported.
</s>
<s id="perforce">
Yes. Changesets are supported.
</s>
<s id="vesta">
Not exactly. Vesta uses a related concept of
configurations instead, which some has similar
properties.
</s>
<s id="co-op">Yes. Changesets are the default.</s>
<s id="vss">No. Changes are file-specific.</s>
<s id="cmsynergy">Yes. Changesets (or tasks) are fundamental
to the way Synergy works.</s>
</compare>
</section>
<section id="annotate">
<title>Tracking Line-wise File History</title>
<expl>
Does the version control system has an option to track the
history of the file line-by-line? I.e: for each line show
at which revision it was most recently changed, and by whom?
</expl>
<compare>
<s id="cvs">Yes. cvs annotate</s>
<s id="subversion">Yes. (svn blame)</s>
<s id="superversion">No.</s>
<s id="svk">Yes. (svk blame)</s>
<s id="bitkeeper">Yes. (bk annotate)</s>
<s id="arch">Not in the command line client, but ViewARCH,
a web-interface for Arch, has it.</s>
<s id="darcs">Yes. (darcs annotate)</s>
<s id="monotone">No.</s>
<s id="aegis">Yes. aeannotate</s>
<s id="opencm">Unknown. Probably not.</s>
<s id="perforce">Yes, an annotation feature is present.</s>
<s id="vesta">
No, but it would be easy to implement a tool that
did this, as the Vesta repository provides direct
filesystem access to all versions.
</s>
<s id="co-op">Not directly, but it's possible to compare
any two versions using a visual differ.
</s>
<s id="vss">Not directly, but it's possible to compare
any two versions using a visual differ.
</s>
<s id="cmsynergy">Probably, if you're a sufficiently proficient hacker with
their scripting language.
</s>
</compare>
</section>
</section>
<section id="features">
<title>Features</title>
<section id="work_on_dir">
<title>Ability to Work only on One Directory of the Repository</title>
<expl>
Can the version control system checkout only one directory of
the repository? Or restrict the check-ins to only one
directory?
</expl>
<compare>
<s id="cvs">Yes.</s>
<s id="subversion">Yes.</s>
<s id="superversion">No.</s>
<s id="svk">Yes.</s>
<s id="bitkeeper">No. All changes are made repository-wide.</s>
<s id="arch">
It is possible to commit only a certain directory.
However, one must check out the entire repository as a
whole.
</s>
<s id="darcs">
It is possible to commit only a certain directory.
However, one must check out the entire repository as a
whole.
</s>
<s id="aegis">No. All changes are made repository-wide.</s>
<s id="monotone">No. All changes are tree-wide.</s>
<s id="opencm">No. All changes are made to a project as
a unit
</s>
<s id="perforce">
Yes. Changes to a sub-directory of the repository
are supported.
</s>
<s id="vesta">
Yes and no. The unit of checkout/checkin (called a
package) is a directory tree. Most projects use
more than one. Once created, a package must be
checked out/in as a unit.
</s>
<s id="co-op">No. All changes are made to a project as
a unit, but it's possible to access each file's
history separately.
</s>
<s id="vss">Yes.</s>
<s id="cmsynergy">Yes and no. Files and directories are checked out and in
individually, however you have to work in the context of a project,
which consists of one or more directories.</s>
</compare>
</section>
<section id="tracking_uncommited_changes">
<title>Tracking Uncommited Changes</title>
<expl>
Does the software has an ability to track the changes in the
working copy that were not yet commited to the repository?
</expl>
<compare>
<s id="cvs">Yes. Using cvs diff</s>
<s id="subversion">Yes. Using svn diff</s>
<s id="superversion">Yes. Local changes are detected and shown immediately. Changes can be
collected in a local buffer before being committed to the repository.</s>
<s id="svk">Yes. Using svk diff</s>
<s id="bitkeeper">Yes. Using bk diff.</s>
<s id="arch">
Yes, using "tla changes".
</s>
<s id="darcs">
Yes, using "darcs whatsnew".
</s>
<s id="aegis">Yes. Using aediff</s>
<s id="monotone">Yes. In a similar fashion to CVS.</s>
<s id="opencm">Yes. Using cm diff</s>
<s id="aegis">Yes. Using aediff.</s>
<s id="perforce">Yes.</s>
<s id="vesta">
Yes. Intermediate immutable snapshots can be
taken during an active checkout (with vadvance).
These intermediate versions can be treated just
like checked in versions: they can be replicated
to other repositories and used as the basis for
branches.
</s>
<s id="co-op">Yes, using built-in visual differ/editor.</s>
<s id="vss">Yes, using integrated diff tool.</s>
<s id="cmsynergy">Yes, either using integrated diff tool or user-configured
external diff tool</s>
</compare>
</section>
<section id="per_file_commit_messages">
<title>Per-File Commit Messages</title>
<expl>
Does the system has a way to assign a per-file commit message
to the changeset, as well as a per-changeset message?
</expl>
<compare>
<s id="cvs">No. Commit messages are per change.</s>
<s id="subversion">No. There is no such feature.</s>
<s id="superversion">Yes.</s>
<s id="svk">No. There is no such feature.</s>
<s id="bitkeeper">Yes. It is possible to have a per-file
commit message</s>
<s id="arch">
No.
</s>
<s id="darcs">
No.
</s>
<s id="monotone">
Yes. It is possible to attach a comment to a certain
file at a certain revision.
</s>
<s id="opencm">
Unknown.
</s>
<s id="perforce">
No. Commit messages are per change.
</s>
<s id="vesta">
Not exactly. The unit of checkin is a directory,
and commit messages are assigned at that level,
not to individual files. Since configurations are
also versioned, they also have commit messages.
</s>
<s id="co-op">No. Commit messages are per change.
They go to all project members and update
their repositories.
</s>
<s id="vss">Since changesets are not supported, yes.</s>
<s id="cmsynergy">Yes.</s>
</compare>
</section>
</section>
<section id="technical_status">
<title>Technical Status</title>
<section id="documentation">
<title>Documentation</title>
<expl>
How well is the system documented? How easy it is to
get started using it?
</expl>
<compare>
<s id="cvs">Excellent. There are many online tutorials and
resources and an online book. The command line client
also provides an online comprehensive help system.
</s>
<s id="subversion">
Very good. There is a free online book and some online
tutorials and resources. The book is written in
DocBook/XML and so is convertible to many different
formats. The command-line client also provides a good
online help system that can be used as a reference.
</s>
<s id="superversion">
Fairly poor. There are two tutorials, but there is no
reference. Installing and getting started with the GUI
is very easy though.
</s>
<s id="svk">
Very poor at this moment.
</s>
<s id="aegis">
Medium. The documentation is given in several large scope
troff documents, that are only usable as not-so-PDFish
PDF documents, and as text documents that lack any
formatting. It is very hard to get started using
it with the online resources. The content is of good
quality, but otherwise not made very accessible.
</s>
<s id="arch">
Medium. There are two online tutorials and a
comprehensive online documentation. The command line
client also supplies a reference page. However, some of
the documentation is out of date or incomplete.
</s>
<s id="darcs">
Good. The manual contains a brief tutorial and a solid
reference. Every sub-command can print its usage.
Because the command-set is small and the model is
simple, many users find it easy to get started.
</s>
<s id="bitkeeper">
Very good. There is a comprehensive help at the BitKeeper
site. Each command is documented in its own man page,
and the client contains a help tool that offers
an integrated help system.
</s>
<s id="monotone">
Good. There's an overview and tutorial written in Texi,
and a man page. The client supplies documentation for
every command.
</s>
<s id="opencm">
Well documented.
</s>
<s id="perforce">
Very Good (html and command line help)
</s>
<s id="vesta">
Quite thoroughly (HTML, man pages, published
papers, a book-length research report).
</s>
<s id="co-op">Very good. Step-by-step tutorial and HTML help
is included.
</s>
<s id="vss">Medium. Help file which is sometimes useful.
However, the interface is reasonably intuitive so
documentation isn't needed as much.
</s>
<s id="cmsynergy">Medium. Lots of books, plus somewhat
clunky set of HTML pages, but has some radical concepts
which can cause real problems really quickly. They recommend
a day's training for basic users, more for more advanced users.
Took a while to become fluent.
</s>
</compare>
</section>
<section id="ease_of_deployment">
<title>Ease of Deployment</title>
<expl>
How easy it is to deploy the software? What are
the depenedencies and how can they be satisfied?
</expl>
<compare>
<s id="cvs">
Good. Out of being the de-facto standard,
CVS is available on most systems and is easy
to deploy.
</s>
<s id="arch">
Excellent. An arch service is nothing but a
filesystem-space hosted by any of its supported
protocols (FTP, SFTP, WebDAV, etc.). The arch client
is written in C, and is portable across UNIX systems
(and on Win32 only with a UNIX emulation layer).
</s>
<s id="darcs">
Very good. darcs requires few external libraries,
however you need the Glasgow Haskell Compiler if you
cannot find a binary. To start working, just "darcs
init".
</s>
<s id="bitkeeper">
Good. All that is required is downloading a binary
for the system and installing it using the installation
script. The package is self-contained and is easy to
set up.
</s>
<s id="aegis">
The Aegis binary should be installed as SUID-root, and
so requires root privileges to install. It also not very
portable to Win32 systems. Other than that, Aegis supports
an easy autoconf or RPM/apt-based installation process.
</s>
<s id="subversion">
A Subversion service requires installing an Apache 2
module (if one wishes to use HTTP as the underlying
protocol) or its own proprietary server. The client
requires only the Subversion-specific logic and the
Neon WebDAV library (for HTTP). Installation of the
components is quite straightforward, but will require
some work, assuming Subversion does not come prepackaged
for one's system.
</s>
<s id="superversion">
If Java 1.4 is installed, deployment of Superversion
usually takes two clicks.
</s>
<s id="svk">
In addition to installing subversion, users are required
to install the subversion perl bindings and a few modules
from CPAN.
</s>
<s id="monotone">
Excellent. It is possible to copy or compile the executable
to the user's machine, without any configuration or
external dependencies.
</s>
<s id="opencm">
Very good. Install the RPM, or build from tarball and
install the init script.
</s>
<s id="perforce">
Very good. Perforce is very easy to deploy.
</s>
<s id="vesta">
Medium to Good. There is a detailed installation guide
for setting it up using a binary kit. RPMs and
Debian packages have been recently released.
There are no dependencies on other software.
Vesta, however, is required to build itself.
</s>
<s id="co-op">Very easy to deploy, since there is no central
server. Can be configured to use e-mail or LAN (or both) for
synchronization. For e-mail, requires MAPI-compliant
e-mail client.
</s>
<s id="vss">
Very good - an installation package which does the work.
When you create a repository it installs the exe's in a
directory and you can run them from there if you need to.
</s>
<s id="cmsynergy">
Medium. There is a detailed install guide for
setting it up using a binary kit and a set of scripts. However
it still took several tries to get it properly installed and
configured. The Windows client is a slightly clunky Windows
installer.
</s>
</compare>
</section>
<section id="command_set">
<title>Command Set</title>
<expl>
What is the command set? How compatible it is with
the commands of CVS (the current open-source defacto
standard)?
</expl>
<compare>
<s id="cvs">
A simple command set that includes three most commonly
used commands (cvs commit, cvs update and cvs checkout)
and several others.
</s>
<s id="subversion">
A CVS-like command set which is easy to get used to
for CVS-users.
</s>
<s id="superversion">
There is little need to memorize a command set because
all actions take place in a GUI. A part of the terminology
used in the application is borrowed from CVS.
</s>
<s id="svk">
A CVS-like command set which is easy to get used to
for CVS-users.
</s>
<s id="bitkeeper">
A CVS-like command set with some easy-to-get-used-to
complications due to its different way of work and
philosophy.
</s>
<s id="aegis">
A complex command set that involves many operations
just to get started. Not CVS-compatible. (albeit
support for such basic operations was contemplated)
Note that Aegis is a Software Configuration Management
system and not just a simple version control system,
which may justify this extra complexity.
</s>
<s id="arch">
Many commands are compatible with CVS or BitKeeper. However,
there are many other commands for it for different uses.
Aliasing of commands is possible so it it may be possible
to make it more compatible.
</s>
<s id="darcs">
The command set is fairly compact and the core commands
are easy to understand. Follows CVS in a few places,
but since the model is different most commands are
unique.
</s>
<s id="monotone">
Tries to follow CVS conventions, but deviates where there
is a different design.
</s>
<s id="opencm">
A CVS-like command set that is familiar to existing CVS
users.
</s>
<s id="perforce">
Very extensive but not compatible with CVS.
</s>
<s id="vesta">
The command set is unrelated to CVS. Most of the
time, users use about 5 commands. Few ever need
to know more than about 20 commands.
</s>
<s id="co-op">Basic commands are compatible with CVS.</s>
<s id="vss">
A bit of an afterthought. It's possible to do basic
things, but it's really geared up for using the GUI.
</s>
<s id="cmsynergy">An extensive and powerful command set,
which has some CVS similarity, though the architecture
is so different that it quickly moves away for anything
but the basics.
</s>
</compare>
</section>
<section id="networking">
<title>Networking Support</title>
<expl>
How well is the networking integration in the system?
How compliant it with existing protocols and infra-structure.
</expl>
<compare>
<s id="cvs">
Good. CVS uses a proprietary protocol with various
variations for its client/server protocol. This protocol
can be tunneled over an SSH-connection to support
encryption.
</s>
<s id="arch">
Excellent. Arch can utilize a multitude of protocols
for its service, which is nothing but a dumb remote
filesystem server. Currently supported protocols include
FTP, SFTP, WebDAV (remote file access over HTTP),
as well as any remote filesystem protocol (NFS, SMB).
</s>
<s id="darcs">
Good. Darcs supports getting patches over HTTP, and
getting and sending patches over SSH and email.
</s>
<s id="subversion">
Very good. The Subversion service can use either
WebDAV+DeltaV (which is HTTP or HTTPS based) as its
underylying protocol, or its own proprietary protocol
that can be channeled over an SSH connection.
</s>
<s id="superversion">
Good. Network support based on RMI is integrated
seamlessly. Encryption and HTTP tunnelling are planned
for the near future.
</s>
<s id="svk">
Very good. svk uses SVN::Mirror to retrieve remote
repository. There has been plans to add VCP support
to SVN::Mirror so it will be able to mirror from arbitary
remote version control systems.
</s>
<s id="bitkeeper">
Good. Repositories can be checked out from remote
over HTTP, and BitKeeper also sports its own proprietary
protocol for communicating between one repository and
the other.
</s>
<s id="aegis">
Poor. Aegis is filesystem-oriented and so can be networked
only via NFS (network file-system) or a similar protocol.
There exists some HTTP-functionality, but it is quite
limited.
</s>
<s id="monotone">
Good. Uses a custom protocol called "netsync".
</s>
<s id="opencm">
Good. Uses its own proprietary client/server protocol.
</s>
<s id="perforce">
Good. (single TCP/IP socket)
</s>
<s id="vesta">
Networking is inherent to the system. The
repository exports both an NFS interface and an
RPC interface. The checkout and checkin tools
automatically contact a remote repository when
required to perform an operation.
</s>
<s id="co-op">Uses the simplest LAN interface:
copying files between shared directories.
</s>
<s id="vss">
VSS uses a Windows network share which has to be writable
for the VSS users (since this means doubling maintenance
for new users). Add user in VSS and to share permissions.
the share is most often world-writable, as is the default
when creating a share) It does not perform well over a
slow network connection.
</s>
<s id="cmsynergy">Good (single TCP/IP socket)</s>
</compare>
</section>
<section id="portability">
<title>Portability</title>
<expl>
How portable is the version-control system to various
operating systems, computer architectures, and other
types of systems?
</expl>
<compare>
<s id="cvs">Good. Client works on UNIX, Windows and Mac OS.
Server works on UNIXes and on Windows with a UNIX
emulation layer.
</s>
<s id="subversion">
Excellent. Clients and Servers work on UNIX,
Windows and Mac OS X.
</s>
<s id="superversion">
Excellent. Clients and servers work on any Java
1.4-compatible platform. There is official support
for Windows, Linux and OS/2.
</s>
<s id="svk">
Good. Clients requires subversion and its perl bindings.
</s>
<s id="bitkeeper">
Very good. Binaries are available for most common UNIX
systems and for Windows 98 and above.
</s>
<s id="aegis">
Medium. The source is portable across all UNIXes,
but the Windows version work only using cygwin, and even
then not entirely natively.
</s>
<s id="arch">
Good. The source is portable across all UNIXes,
but requires a UNIX emulation layer on Windows. (need to
verify). A service can be hosted on any platform
that sports a suitable Internet service.
</s>
<s id="darcs">
Very good. Supports many UNIXes, Mac OS X, and Windows,
and is written in a portable language.
</s>
<s id="monotone">
Excellent. Executable is portable across all UNIXes and
Win32.
</s>
<s id="opencm">
Good. Portable across all UNIX systems.
</s>
<s id="perforce">
Excellent. Runs on UNIX, Mac OS, BeOS and Windows.
</s>
<s id="vesta">
Good. It should be portable to any UNIX system.
Currently it runs on Digital/Compaq/HP Tru64 UNIX
and Linux on several different CPU architectures.
Ports to Solaris and FreeBSD are planned but
haven't begun yet.
</s>
<s id="co-op">Windows only: starting with Win95.</s>
<s id="vss">
The Microsoft Product is Windows only.
<a href="http://www.mainsoft.com/">MainSoft</a>
ships a version of it for some UNIX platforms.
</s>
<s id="cmsynergy">
Very good - various flavours of Unix,
Windows (only NT family for the server), VMS, and
possibly other systems.
</s>
</compare>
</section>
</section>
<section id="user_interaces">
<title>User Interfaces</title>
<section id="web_interface">
<title>Web Interface</title>
<expl>
Does the system have a WWW-based interface that can be
used to browse the tree and the various revisions of the
files, perform arbitrary diffs, etc?
</expl>
<compare>
<s id="cvs">Yes.
WebCVS, <a href="http://viewcvs.sourceforge.net/">ViewCVS</a>,
and <a href="http://www.horde.org/chora/">Chora</a>.
</s>
<s id="bitkeeper">Yes. Its own built-in web-interface.</s>
<s id="subversion">Yes.
<a href="http://viewcvs.sourceforge.net/">ViewCVS</a>,
<a href="http://freshmeat.net/projects/svnweb/">SVN::Web</a>,
<a href="http://websvn.tigris.org/">WebSVN</a>,
<a href="http://viewsvn.berlios.de/">ViewSVN</a>,
<a href="http://www.outoforder.cc/projects/apache/mod_svn_view/">mod_svn_view</a>,
<a href="http://www.horde.org/chora/">Chora</a>,
<a href="http://www.edgewall.com/trac/">Trac</a>, and
<a href="http://web-cpan.berlios.de/modules/SVN-RaWeb-Light/">SVN::RaWeb::Light</a>.
Aside
from that, the Subversion Apache service provides a
rudimentary web-interface.
</s>
<s id="superversion">No.</s>
<s id="svk">Yes. Same as Subversion.</s>
<s id="arch">
There's <a href="http://arch.bluegate.org/viewarch.html">ViewARCH</a>, and
<a href="http://migo.sixbit.org/software/archzoom/">ArchZoom</a>
which are
works in progress.
</s>
<s id="darcs">
<a href="http://abridgegame.org/cgi-bin/darcs.cgi/darcs/">darcs.cgi</a>
is included in the distribution.
</s>
<s id="aegis">Yes.</s>
<s id="monotone">No.</s>
<s id="opencm">No.</s>
<s id="perforce">Yes, P4Web.</s>
<s id="vesta">
Yes: <a href="http://www.scooter.cx/vestaweb/">Vestaweb</a>.
</s>
<s id="co-op">Since this functionality is always
available locally, there is no need for web interface.
</s>
<s id="vss">
It is possible to code one using the API, but no official
or third-party one exists.
</s>
<s id="cmsynergy">Possibly.</s>
</compare>
</section>
<section id="availability_of_guis">
<title>Availability of Graphical User-Interfaces.</title>
<expl>
What is the availability of graphical user-interfaces for
the system? How many GUI clients are present for it?
</expl>
<compare>
<s id="cvs">Very good. There are many available GUIs:
WinCVS, Cervisia (for KDE),
TortoiseCVS (Windows Explorer plug-in).
</s>
<s id="bitkeeper">Good. BitKeeper ships with several
GUIs for performing common tasks. I'm not aware
of any third-part GUIs.
</s>
<s id="subversion">Very good. There are many available
GUIs: RapidSVN (cross-platform),
TortoiseSVN (Windows Explorer plug-in), Jsvn (Java), etc.
Most of them are still under development.
</s>
<s id="superversion">
A GUI is integrated.
</s>
<s id="svk">
No GUIs are available.
</s>
<s id="arch">
There are
<a href="http://www.ibe.miee.ru/tlator/">tlator</a>,
<a href="http://www.hpl.hp.com/personal/Yasushi_Saito/octopy/">Octopy</a>,
and <a href="http://www.nongnu.org/archway/">ArchWay</a>
and possibly others under development.
</s>
<s id="darcs">
None to speak of. (There is a modest graphical
interface to a few commands in the distribution, but it
is not being developed currently.)
</s>
<s id="aegis">
There is tkaegis.
</s>
<s id="monotone">
No GUIs are available.
</s>
<s id="opencm">
No GUIs are available.
</s>
<s id="perforce">
Yes, P4Win and others based on the available libp4
library.
</s>
<s id="vesta">
No GUIs are available, but the repository has a
C++ API, and it's not be hard to write one. (At
least three different project-specific ones have
been written by users at Compaq and Intel.)
</s>
<s id="co-op">The system is GUI-based by design.</s>
<s id="vss">
Standalone GUI comes with it, plus SCCI plug-in for
MS Visual Developer Studio. There is an Eclipse
plug-in.
</s>
<s id="cmsynergy">
A couple of GUIs. A motif-based one
(even on Windows) allows most functionality but is clunky.
A nicer Java one allows developer work but not much
administrative stuff. Has an SCCI plug-in, though it
doesn't handle network problems well.
</s>
</compare>
</section>
</section>
<section id="license">
<title>License</title>
<expl>
What are the licensing terms for the software?
</expl>
<compare>
<s id="cvs">GNU GPL (open source)</s>
<s id="arch">GNU GPL (open source)</s>
<s id="darcs">GNU GPL (open source)</s>
<s id="bitkeeper">
Proprietary, binary only license. Comes in
two versions: gratis and pay per use. The gratis license
is intended for development of free software only and is
<a href="bk-license.html">problematic</a>. The pay
per use license is free of most of its problems.
</s>
<s id="aegis">
GNU GPL (open source)
</s>
<s id="subversion">
Apache/BSD-style license. (open-source)
</s>
<s id="superversion">
GNU GPL (open-source)
</s>
<s id="svk">Perl License. (open source)</s>
<s id="monotone">GNU GPL (open source)</s>
<s id="opencm">
GNU GPL (open source), but moving soon to
BSD or CPL (also open source).
</s>
<s id="perforce">
A proprietary, binary only, commercial license.
<a href="http://perforce.com/perforce/price.html">Price
starting at $750 per seat for the first year</a> and then
$150 for continuing support for the subsequent years. Free for
Open Source projects (no support in this case).
</s>
<s id="vesta">
GNU LGPL (open source)
</s>
<s id="co-op">Proprietary, short text key. 30-day
full-featured trial. Free to "observers"
(members who don't make changes).
$159 per workstation.
</s>
<s id="vss">
VSS Ships with MSDN, and can also be purchased
stanalone or with other tools.
</s>
<s id="cmsynergy">
Prices negotiable with salesman.
Server is typically roughly 20,000 British Pounds.
Clients are 4,000 British Pounds. Per-year costs of 18%
of original.
</s>
</compare>
</section>
</section>
</contents>
</comparison>