[LLVMdev] [Zorg] Reorganisation, documentation and other issues

[Dan Liew]

Hi All,

Recent conversations [1][2] would suggest we need to rethink zorg or
at the very least improve the documentation.

I've CC'ed Daniel Dunbar, Galina Kistanova and Duncan Sands because it
seemed that they have contributed the most code to Zorg

Organisation
=========

The current organisation of the Zorg repository doesn't make a huge
amount of sense from my perspective. There are two things that we
should be able to do with this code

- Run the currently in use buildbot master.
- Run a builtbot master and slave on a local machine for testing.

The current project layout doesn't seem to facilitate either of these
needs particularly well. If we take a look at
``/buildbot/osuosl/master`` the ``zorg`` folder isn't in here so the
``master.cfg`` adds a non portable hack to load the zorg code (assumes
zorg is in user's home directory).

Unless there is a good reason for doing so I think the zorg modules
should be moved into the master buildbot directory so this hack isn't
necessary. If there is a really good reason for doing this we should
document this so people can actually run the buildbot master on their
own machine.

The ``master.cfg`` file is also full of stuff that is not suited for
testing a master and slaves hosted on the same machine.

* Buildbot master should only listen on localhost (no out going connections)
* Buildbot master should have no authorisation and show the web
interface so manual builds are easy to trigger
* Buildbot master should not use the large list of slaves because a
locally hosted master cannot connect to these because they shouldn't
be contacted for testing (it doesn't have the passwords for these
buildbot slaves either).
* Buildbot should load slaves from a file not under version control
for local testing.

Either we need to make it so that the buildbot master
(/buildbot/osuosl/master) can operate in two modes (normal and
localhost testing) or we need to provide another buildbot master
configuration for localhost testing. I think this is what
``buildbot/smooshlab`` is for but that code has not been touched in
ages and is probably dead (if it is dead, we should delete it).


Other issues
==========

* Ancient version of buildbot.

Why do we use buildbot 0.8.5? Newer versions are available in Pypi
which anyone using Python can install. I have issues with 0.8.5 and I
have to patch it before it will actually work. I don't think we should
have in our documentation that you need to patch buildbot, we should
just upgrade to a newer version.

* reload()

I see lots of reload() all over the place. Why do we need these?
Surely if you do

$ buildbot stop master
$ buildbot start master

This would reload everything making uses of ``reload()`` pointless.

* KLEE stuff

KLEE is no longer actively developed as part of LLVM so all this stuff
should be dropped from Zorg.

* Lack of documentation
This can be addressed once we fix the other issues.

* Builders

There are lots of python modules in ``zorg/zorg/buildbot/builders``.
These are Factories, not builders so why do they have ``Builder`` in
their name and are in the "builders" folder? This is unnecessarily
confusing.

* llvmlab, osuosl, smooshlab?

Not sure those names are particularly helpful. I suspect ``smooshlab``
will probably be removed entirely and I suspect osuosl ought to be
renamed. I'm not sure if we need to keep any of the llvmlab stuff.

This is probably an incomplete list of issues but theses are issues I
have observed in my brief time playing with Zorg and buildbot.

[1] http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/075287.html
[2] http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/075348.html


Thanks,
Dan.