Remove GIT notes

These notes describe how to use TopGit with this repo.  As of
this point TopGit is no longer used so the notes have been removed.

Signed-off-by: Brian Behlendorf <[email protected]>

1 files changed, 0 insertions, 197 deletions

diff --git a/GIT b/GIT
deleted file mode 100644
index 5293cb5ed..000000000
--- a/GIT
+++ /dev/null
@@ -1,197 +0,0 @@
-=========================== WHY USE GIT+TOPGIT? ==========================
-
-Three major concerns were on our mind when setting up this project.
-
-  o First we needed to structure the project in such a way that it would be
-    easy to rebase all of our changes on the latest official ZFS release
-    from Sun.  We absolutely need to be able to benefit from the upstream
-    improvements and not get locked in to an old version of the code base.
-
-  o Secondly, we wanted to be able to easily manage our changes in terms
-    of a patch stack or graph.  This allows us to easily isolate specific
-    changes and push them upstream for inclusion.  It also allows us to 
-    easily update or drop specific changes based on what occurs upstream.
-
-  o Thirdly we needed our DVCS to be integrated with the management of this
-    patch stack or graph.  We have tried other methods in the past such as
-    SVN+Quilt but have found managing the patch stack becomes cumbersome.
-    By using Git+TopGit to more tightly integrate our patches in to the repo
-    we expect several benefits.  One of the most important will be the
-    ability to easily work on the patch's with a distributed development
-    team, additionally the repo can track patch history, and we can utilize
-    Git to merge patches and resolve conflicts.
-
-TopGit is designed to specifically address these concerns by providing 
-tools to simplify the handling of large numbers of interdependent topic 
-branches.  When using a TopGit aware repo every topic branch represents
-a 'patch' and that branch references its dependent branches.  The union
-of all these branches is your final source base.
-
-========================= SETTING UP GIT+TOPGIT ==========================
-
-First off you need to install a Git package on your system.  For my
-purposes I have been working on a RHEL5 system with git version 1.5.4.5
-installed and it has been working well.  You will also need to go get
-the latest version of TopGit which likely is not packaged nicely so you
-will need to build it from source.  You can use Git to clone TopGit
-from the official site here and your all set:
-
-        > git clone git://repo.or.cz/topgit.git
-        > make
-        > make install    # Default installs to $(HOME)
-
-========================== TOPGIT AND ZFS ================================
-
-One you have Git and TopGit installed you will want to clone a copy of
-the Linux ZFS repo.  While this project does not yet have a public home
-it hopefully will some day.  In the meanwhile if you have VPN access to
-LLNL you can clone the latest official repo here.  Cloning a TopGit
-controlled repo is very similar to cloning a normal Git repo, but you
-need to remember to use 'tg remote' to populate all topic branches.
-
-        > git clone git://eris.llnl.gov/zfs.git
-        > cd zfs
-        > tg remote --populate origin
-
-Alternately, if you don't want to worry about using TopGit on your system
-you can simply clone the repo and then checkout the origin/top branch.  At
-this point you can simply create a new branch to track your changes.  You
-can then feed your patch back to the official repo maintainers to be merged
-in to the proper topic branches.
-
-	> git clone git://eris.llnl.gov/zfs.git
-	> cd zfs
-	> git checkout origin/top
-	> git checkout -b <new_branch_name>
-
-Now that you have the Linux ZFS repo the first thing you will probably 
-want to do is have a look at all the topic branches.  TopGit provides
-a summary command which shows all the branches and a brief summary for
-each branch obtained from the .topmsg files.
-
-        > tg summary
- 0      feature-branch                  [PATCH] feature-branch
-        feature-commit-cb               [PATCH] feature commit cb
-        feature-zap-cursor-to-key       [PATCH] feature zap cursor to key
-        ...
-
-By convention all TopGit branches are usually prefixed with 't/', however
-I have chosen not to do this for simplicity.  A different convention I have
-adopted is to tag the top most TopGit branch as 'top' for easy reference.
-This provides a consistent label to be used when you need to reference the
-branch which contains the union of all topic branches.
-
-One thing you may also notice about the 'tg summary' command is it does
-not show the branches in dependent order.  This is done because TopGit allows
-each branch to express multiple dependencies as a DAC.  Initially this seemed
-like an added complication which I planned to avoid by just implementing a
-stack using the graph.   However, this ended up being problematic because
-with a stack when a change was made to a branch near the base, it was a
-very expensive operation to merge the change up to the top of the stack.
-By defining the dependencies as a graph it is possible to keep the depth
-much shallower thus minimizing the merging.  It has also proved insightful
-as to each patches actual dependencies.
-
-To see the dependencies you will need to use the --graphviz option and pipe
-the result to dot for display.  The following command works fairly well for
-me.  Longer term it would be nice to update this option to use a preferred
-config options stored in the repo.
-
-        > tg summary --graphviz | dot -Txlib -Nfontsize=8
-
-========================= UPDATING A TOPIC BRANCH ========================
-
-Updating a topic branch in TopGit is a pretty straight forward but there
-are a few rules you need to be aware of.  The basic process involves 
-checking out the relevant topic branch where the changes need to be made,
-making the changes, committing the changes to the branch and then merging
-those changes in to dependent branches.  TopGit provides some tools to make
-this pretty easy, although it may be a little sluggish depending on how many
-dependent branches are impacted by the change.  Here is an example:
-
-        > git checkout modify-topic-branch  # Checkout the proper branch
-        > ...update branch...               # Update the branch
-        > git commit -a                     # Commit your changes
-        > git checkout top                  # Checkout the top branch
-        > tg update                         # Recursively merge in new branch
-
-Assuming you change does not introduce any conflicts your done.  All branches
-were dependent on your change will have had the changed merged in.  If your
-change introduced a conflict you will need to resolve the conflict and then
-continue on with the update.
-
-========================== ADDING A TOPIC BRANCH =========================
-
-Adding a topic branch in TopGit can be pretty straight forward.  If your 
-adding a non-conflicting patch in parallel with other patches of the same
-type, then things are pretty easy and TopGit does all the work.
-
-        > git co existing-topic-branch      # Checkout the branch to add after
-        > tg create new-topic-branch        # Create a new topic branch
-        > ...update .topmsg...              # Update the branch message
-        > ...create patch...                # Update with your changes
-        > git commit -a                     # Commit your changes
-        > git co dependent-topic-branch     # Checkout dependent branch
-        > tg depend add new-topic-branch    # Update dependencies 
-        > git checkout top                  # Checkout the top branch
-        > tg update                         # Recursively merge in new branch
-
-If you need to add your patch in series with another change things are
-a little more complicated.  In this case TopGit does not yet support removing
-dependencies so you will need to do it by hand, as follows.
-
-        > git co existing-topic-branch      # Checkout the branch to add after
-        > tg create new-topic-branch        # Create a new topic branch
-        > ...update .topmsg...              # Update the branch message
-        > ...create patch...                # Update with your changes
-        > git commit -a                     # Commit your changes
-        > git co dependent-topic-branch     # Checkout dependent branch
-        > ...update .topdeps...             # Manually update dependencies
-        > git commit -a                     # Commit your changes
-        > tg update                         # TopGit update
-        > git checkout top                  # Checkout the top branch
-        > tg update                         # Recursively merge in new branch
-
-Once your done, I find it is a good idea view the repo using the  
-'tg summary --graphviz' command and verify the updated dependency graph.
-
-========================= REMOVING A TOPIC BRANCH ========================
-
-Removing a topic branch in TopGit is also currently not very easy.  To remove
-a dependent branch the basic process is to commit a patch which reverts all
-changes on the branch.  Then that reversion must be merged in to all dependent
-branches, the dependencies manually updated and finally the branch removed.
-If the branch is not empty you will not be able to remove it.
-
-        > git co delete-topic-branch        # Checkout the branch to delete
-        > tg patch | patch -R -p1           # Revert all branch changes
-        > git commit -a                     # Commit your changes
-        > git checkout top                  # Checkout the top branch
-        > tg update                         # Recursively merge revert
-        > git co dependent-topic-branch     # Checkout dependent branch
-        > ...update .topdeps...             # Manually update dependencies
-        > git commit -a                     # Commit your changes
-        > tg delete delete-topic-branch     # Delete empty topic branch
-
-Once your done, I find it is a good idea view the repo using the  
-'tg summary --graphviz' command and verify the updated dependency graph.
-
-============================ TOPGIT TODO =================================
-
-TopGit is still a young package which seems to be under active development
-by its author.  It provides the minimum set of commands needed but there
-are clearly areas which simply have not yet been implemented.  My short
-list of features includes:
-
-  o 'tg summary --deps', option to display a text version of the topic
-    branch dependency DAC.
-
-  o 'tg depend list', list all topic branch dependencies.
-
-  o 'tg depend delete', cleanly remove a topic branch dependency.
-
-  o 'tg create', cleanly insert a topic branch in the middle
-    of the graph and properly take care updating all dependencies.
-
-  o 'tg delete', cleanly delete a topic branch in the middle
-    of the graph and properly take care updating all dependencies.