+
+Database maintenance
+====================
+
+Git object database and other files/directories under ``.git`` require
+periodic maintenance and cleanup. For example, commit editing left
+unreferenced objects (dangling objects, in git terminology) and these
+objects should be pruned to avoid collecting cruft in the DB. The
+command ``git gc`` is used for maintenance. Git automatically runs
+``git gc --auto`` as a part of some commands to do quick maintenance.
+Users are recommended to run ``git gc --aggressive`` from time to
+time; ``git help gc`` recommends to run it every few hundred
+changesets; for more intensive projects it should be something like
+once a week and less frequently (biweekly or monthly) for lesser
+active projects.
+
+``git gc --aggressive`` not only removes dangling objects, it also
+repacks object database into indexed and better optimized pack(s); it
+also packs symbolic references (branches and tags). Another way to do
+it is to run ``git repack``.
+
+There is a well-known `message
+<https://gcc.gnu.org/ml/gcc/2007-12/msg00165.html>`_ from Linus
+Torvalds regarding "stupidity" of ``git gc --aggressive``. The message
+can safely be ignored now. It is old and outdated, ``git gc
+--aggressive`` became much better since that time.
+
+For those who still prefer ``git repack`` over ``git gc --aggressive``
+the recommended parameters are ``git repack -a -d -f --depth=20
+--window=250``. See `this detailed experiment
+<http://vcscompare.blogspot.ru/2008/06/git-repack-parameters.html>`_
+for explanation on the effects of these parameters.
+
+From time to time run ``git fsck [--strict]`` to verify integrity of
+the database. ``git fsck`` may produce a list of dangling objects;
+that's not an error, just a reminder to perform regular maintenance.