Always Run the RelStorage Tests

I would like to advise all users of RelStorage to run the RelStorage test suite on their staging and production servers before running any application that uses RelStorage.  There are a number of ways to misconfigure the database and the tests will reveal many kinds of issues.  The test suite is in very good shape and should pass every test, every time.

Here are a few MySQL-specific misconfigurations that the tests will reveal:

  • An incorrect database adapter.  For example, Debian Etch still ships MySQLdb 1.2.1, causing most of the tests to fail.
  • Insufficient packet size.  In my.cnf, you should increase max_allowed_packet from 16M to at least 32M.  This parameter limits the maximum size of an object stored by RelStorage.
  • Insufficient space in /tmp.  You need a lot more than 16M available, but linux-vserver limits /tmp to 16M by default.

To run the suite, do something like this:

cd /path/to/relstorage
export PYTHONPATH=`pwd`:/path/to/ZODB/src
python relstorage/tests/  # or or

Personally, every time I run these tests on a new database, I discover something misconfigured.  It is worth the time to run the tests.