2017-08-29 06:56:59 -04:00
|
|
|
# Migrating from Perforce Helix
|
|
|
|
|
|
|
|
|
|
[Perforce Helix](https://www.perforce.com/) provides a set of tools which also
|
|
|
|
|
include a centralized, proprietary version control system similar to Git.
|
|
|
|
|
|
2017-08-30 03:59:56 -04:00
|
|
|
## Perforce vs Git
|
|
|
|
|
|
2017-08-29 06:56:59 -04:00
|
|
|
The following list illustrates the main differences between Perforce Helix and
|
|
|
|
|
Git:
|
|
|
|
|
|
|
|
|
|
1. In general the biggest difference is that Perforce branching is heavyweight
|
|
|
|
|
compared to Git's lightweight branching. When you create a branch in Perforce,
|
|
|
|
|
it creates an integration record in their proprietary database for every file
|
|
|
|
|
in the branch, regardless how many were actually changed. Whereas Git was
|
|
|
|
|
implemented with a different architecture so that a single SHA acts as a pointer
|
|
|
|
|
to the state of the whole repo after the changes, making it very easy to branch.
|
|
|
|
|
This is what made feature branching workflows so easy to adopt with Git.
|
|
|
|
|
1. Also, context switching between branches is much easier in Git. If your manager
|
|
|
|
|
said 'You need to stop work on that new feature and fix this security
|
|
|
|
|
vulnerability' you can do so very easily in Git.
|
|
|
|
|
1. Having a complete copy of the project and its history on your local machine
|
|
|
|
|
means every transaction is superfast and Git provides that. You can branch/merge
|
|
|
|
|
and experiment in isolation, then clean up your mess before sharing your new
|
|
|
|
|
cool stuff with everyone.
|
|
|
|
|
1. Git also made code review simple because you could share your changes without
|
|
|
|
|
merging them to master, whereas Perforce had to implement a Shelving feature on
|
|
|
|
|
the server so others could review changes before merging.
|
|
|
|
|
|
|
|
|
|
## Why migrate
|
|
|
|
|
|
|
|
|
|
Perforce Helix can be difficult to manage both from a user and an admin
|
|
|
|
|
perspective. Migrating to Git/GitLab there is:
|
|
|
|
|
|
|
|
|
|
- **No licensing costs**, Git is GPL while Perforce Helix is proprietary.
|
|
|
|
|
- **Shorter learning curve**, Git has a big community and a vast number of
|
|
|
|
|
tutorials to get you started.
|
|
|
|
|
- **Integration with modern tools**, migrating to Git and GitLab you can have
|
|
|
|
|
an open source end-to-end software development platform with built-in version
|
|
|
|
|
control, issue tracking, code review, CI/CD, and more.
|
|
|
|
|
|
|
|
|
|
## How to migrate
|
|
|
|
|
|
|
|
|
|
Git includes a built-in mechanism (`git p4`) to pull code from Perforce and to
|
|
|
|
|
submit back from Git to Perforce.
|
|
|
|
|
|
|
|
|
|
Here's a few links to get you started:
|
|
|
|
|
|
|
|
|
|
- [git-p4 manual page](https://www.kernel.org/pub/software/scm/git/docs/git-p4.html)
|
|
|
|
|
- [git-p4 example usage](https://git.wiki.kernel.org/index.php/Git-p4_Usage)
|
|
|
|
|
- [Git book migration guide](https://git-scm.com/book/en/v2/Git-and-Other-Systems-Migrating-to-Git#_perforce_import)
|
2018-02-26 12:58:57 -05:00
|
|
|
|
|
|
|
|
Note that `git p4` and `git filter-branch` are not very good at
|
|
|
|
|
creating small and efficient Git pack files. So it might be a good
|
|
|
|
|
idea to spend time and CPU to properly repack your repository before
|
|
|
|
|
sending it for the first time to your GitLab server. See
|
|
|
|
|
[this StackOverflow question](https://stackoverflow.com/questions/28720151/git-gc-aggressive-vs-git-repack/).
|
