Re: Work on ext4

On Fri, Jul 25, 2014 at 12:07 PM, Eric Sandeen [off-list ref] wrote:

On 7/25/14, 10:41 AM, Theodore Ts'o wrote:

...

quoted

This will hopefully get you started on the testing side of things,
which is also a good way to start learning about how ext4 works.

Cheers,

                                              - Ted

The old adage on IRC is "Don't ask to ask; ask."  In
development-land, it's more like "Don't ask to help; help."

The trick is knowing what constitutes "help."  Asking for
detailed instruction is not "help."

Over on the btrfs-list, Hugo had a good set of suggestions as
well; some are btrfs-specific, but in general, good advice for
anyone trying to get engaged with an upstream project:

From Hugo -

...

quoted

   My recommendations for you, if you want to work on btrfs, are:

 * Build and install the latest kernel from Linus's git repo

 * Read and understand the user documentation [2]

 * Create one or several btrfs filesystems with different
   configurations and learn how they work in userspace -- what are the
   features, what are the problems you see? Actually use at least one
   of the filesystems you created for real data in daily use (with
   backups)

 * Build the userspace tools from git

 * Pick up one of the userspace projects from [3] and implement that.
   If you pick the right one(s), you'll have to learn about some of
   the internal structures of the FS anyway. Compile and test your
   patch. If you're adding a new feature, write an automated xfstest
   for it as well.

 * Get that patch accepted. This will probably involve a sequence of
   revisions to it, multiple versions over a period of several weeks
   or more, with a review process. You should also send your test to
   xfstests and get that accepted.

 * Do the above again, until you get used to the processes involved,
   and have demonstrated that you can work well with the other people
   in the subsystem, and are generally producing useful and sane code.
   It's all about trust -- can you be trusted to mostly do the right
   thing? (So far on linux-kernel, you've rather demonstrated the
   opposite: your intentions are good, but your execution leaves a lot
   to be desired)

 * Use the documentation at [4], and the output of btrfs-debug-tree to
   understand the internal structure of the FS

 * Pick up one of the smaller, more self-contained ideas from the
   projects page [5] (say, [6] or [7]) and try to implement it. Again:
   build, write test code, test thoroughly, submit patch for review,
   modify as suggested by reviewers, and repeat as often as necessary

   Hugo.

I have got some work in brtfs for now , Ted so I won't
be able to run the tests for you for the next few weeks
probably. Sorry about the issues, but brtfs seems
more work then ext4 as of this point in time.
Nick