ggarber/django-background-task — pull request #1 by smallo (2012-11-13 09:51:17+00:00)
Title:  Change priority order to ASC in tasks query to improve performance 

Since MySQL is not implementing DESC indexes only ASC ordering is optimized [1]. So, it is better to define low numbers of priority being more prioritary. As an example of this definition for priority numbers see unix processes priority [2].

[1] http://dev.mysql.com/doc/refman/5.0/en/order-by-optimization.html
[2] http://www.manpagez.com/man/1/nice/