Svn vs mercurial vs github
- 1. - SEARCH FOR THE BEST RCS vs vs Vinoth Kumar Kannan Vinoth.kannan@widas.de
- 2. THE NEED Why do we need a Revision Control System(RCS) ? • Storing • Retrieval • Logging • Identification • Merging of revisions
- 3. THE CHALLENGERS Apache Subversion - Centralized version control system Mercurial - Python Distributed version control system - Linux based Distributed version control system
- 4. MATCH 1
- 5. • Centralized Version Control Systems (DVCS) Central, authoritative repository All changes saved in one single location Client-Server approach • Distributed Version Control Systems (DVCS) Everyone has their own repository You get the safety net of frequent check-ins without having to worry about „breaking the build‟. Clients can make changes in the repositories and those changes will be local to them unless they synchronize with someone else. Depending on the requirements, Git also offers a centralized repository
- 6. SVN Dataflow Git Data Flow Working Dir Remote Repository
- 7. Online Source Control User must be online in order to commit to the repository from the working copy. Offline Source Control Clients can commit changes to their localized repositories as new revisions even while being offline
- 8. Longer time to store because all of the data is stored in a centralized repository. Extremely Fast Complete copy of the data is stored locally in the client‟s system Very less network response time
- 9. SVN help is more organized There is some time wasted since it is difficult to get a quick reference from Git’s search.
- 10. More Storage Space Two copies of a file in the working directory of SVN One copy is used for storing the actual work while the other copy hidden in .svn/ contains the information used to aid operations (status and commit) When there are a lot of documents, there is a huge impact on disk space in the SVN compared with Git Less Storage Space Has an efficient memory because the data‟s file format is compressed Git has a small index file to store the info related to a particular file
- 11. Creating and working on branch/Merge is complex and difficult to use Simple and Easy to use branch and Merge The working directory of a developer is itself a branch.
- 12. Sequencial Commits Data is lost when simultaneous commits of two or more working copies are performed Non-Sequencial Commits Large number of users can put data to the same repository No need to worry about data lost or immediate merging of others changes
- 13. Merge The facility to merge data is also there in SVN, but it is somewhat incomplete SVN merge records seem to miss some of the important details that Git keeps track of. Merge Users to have control over the merging of data in synchronized repositories. Merges are always pulled by someone and nobody can push to commit merges in someone else’s repository.
- 14. Revision Tracking SVN keeps record of files File history is lost on renaming Fixed by giving a file unique long lived id Revision Tracking Git keeps track of contents. Even a small change in content it tracks it as a separate change. Git needs a global check of the project to determine changes
- 15. Particially Checkout Checkouts at subdirectory level are possible. Only Full Checkout Git will not allow you to checkout a subdirectory. Instead, the user will have to checkout the whole repository.
- 16. Simple usablity Simpler to learn • create, commit and checkout Single central "master-repository” Complex usablity Two modes of creating repositories • checkout vs. clone • commit vs. push. You have to know which commands work locally and which work with "the server“ Git has more concepts and more commands. many Git commands are cryptic, and error messages are very user- unfriendly
- 17. Projects using SVN Projects using Git BitBucket Gitorious Codeplex
- 18. MATCH 1 RESULT 3 : 7
- 20. MATCH 2
- 21. Steep Learning Curve Mercurial's terminology and commands are closer to Subversion and CVS, Easier to migrate Flat Learning Curve More commands More options The volume can be intimidating to new users
- 22. Clean Windows Support Mercurial is Python based The official distribution runs cleanly under Windows (as well as Linux, Mac OS X, etc). Indirect Windows Support Git has a strong Linux heritage Official way to run it under Windows is to use cygwin Not so ideal from the perspective of a Windows user A MinGw based port of Git is gaining popularity, but Windows still remains a “second class citizen” in the world of Git.
- 23. Client Storage Management If a branch is in the local repository, then all of its revisions (back to the very initial commit) must also be present Client Storage Management Git allows previously pulled branches to be discarded. Git also allows old revision data to be pruned from the local repository (while still keeping recent revision data on those branches).
- 24. Slightly slower Branching Branching, merging and tagging systems are equally powerful and only slightly slower. Faster Branching , but… Slightly faster Suffers irregular heavy performance drops
- 25. Bob clones this repo, and ends up with a complete, independent, local copy of Alice's store and a clean checkout of the tipmost revision d in his working directory: Creating Branch and Merging in Mercurial (1)
- 26. Creating Branch and Merging in Mercurial (2)
- 27. Creating Branch and Merging in Mercurial (3) Pull Merge Commit
- 28. Creating Branch and Merging in Mercurial (4)
- 29. Limited Number of Parents Allows only two parents. Unlimited Number of Parents Git supports an unlimited number of parent revisions during a merge
- 30. No Maintenance Mercurial does not require any maintenance. A lot less sophisticated with respect to managing the clients disk space Needs Maintenance Git requires periodic maintenance of repositories Need to run the commad git -gc The Manual of Git Says : “Users are encouraged to run the above mentioned task on a regular basis within each repository to maintain good disk space utilization and good operating performance.”
- 31. Immutable History Structured more as an ever- growing collection of objects whose state cannot be changed after they are created Histories can be changed…. Git is extremely powerful, and will do almost anything you ask it to. Unfortunately, this also means that Git is perfectly happy to lose history. For example,the command git-push --force can result in revisions becoming lost in the remote repository.
- 32. Integration GOOD HTTP SUPPORT: Mercurial has very good support for HTTP based stateless pushing and pulling of remote repositories. Less number of client – server calls All of the relevant information is bundled into a single large transfer. Integration Git includes support for HTTP pulls (and WebDAV pushes), but the implementation assumes that the server knows nothing about Git. It is designed such that you can have a Apache simply serve the Git repository as static content. This method requires numerous synchronous round trip requests
- 33. Fans Fans The following Web sites provide free source code hosting for Git repositories
- 34. Summary In terms of implementation effort, Mercurial has a clear advantage due to its efficient HTTP transport protocol. Much faster if the team size is not large Eclipse supports Mercurial with the MercurialEclipse plugin. Summary In terms of features, Git is more powerful, but this tends to be offset by it being more complicated to use. Social coding : Popular and More suited for shared open source project involving many users. Eclipse supports Git with the EGit plugin.
- 35. SCREENSHOT OF TORTOISE HG GUI CLIENT HISTORY
- 37. MATCH 2 RESULT ? : ?
- 38. WHO DO YOU THINK WON?
- 39. • Reference http://importantshock.wordpress.com/2008/08/07/git-vs-mercurial/ http://code.google.com/p/support/wiki/DVCSAnalysis http://www.ericsink.com/entries/hg_denzel.html http://www.rockstarprogrammer.org/post/2008/apr/06/differences- between-mercurial-and-git/ http://en.wikipedia.org/wiki/Mercurial http://www.wikivs.com/wiki/Git_vs_Mercurial