This issue raises the fact that the 2.X documentation 
lists two logging levels (SUBDEBUG and SUBWARNING) 
without explaining how these two fit into the logging 
hierarchy of the logging levels provided by the standard library logging module
(ie, is SUBDEBUG between INFO and DEBUG). 

The patch (provided by JJeffries and modified by Petri Lehtinen) 
adds an explanatory note stating the hierarchy as follows


These are  :const:`SUBWARNING`,
+which fits between :const:`INFO` and :const:`WARNING` in the normal logging
+hierarchy, and :const:`SUBDEBUG`, which fits below :const:`DEBUG`


Review (this applies to the 2.X version of the documentation)

1. It would be nice to clarify that SUBDEBUG is between DEBUG and NOTSET
instead of saying that it is 'below' as this maybe misunderstood (at least it's not very clear to me). 

2. Slightly unrelated to the main issue of this patch

2a) "In addition to having these two logging functions, the multiprocessing also"

Should be 

"In addition to having these two logging functions, the multiprocessing module also"


3. The documentation for the multiprocessing module in Python 3.X has removed any mention
of SUBWARNING and SUBDEBUG, so I'm not sure if this patch is even relevant anymore?

4. Also, slightly tangent to this patch, but might be nice to pick up is the fact that
documentation for the 2.X version mentions that the logging level table can be viewed in 
the logging module documentation

"For a full table of logging levels, see the logging module."

which is not the case anymore. As Vinay Sajip mentions, in 2.X the logging level table
has moved to the how-to https://docs.python.org/2/howto/logging.html#logging-levels 
and so this link should be updated as well


TODO:
1. Check if SUBWARNING and SUBDEBUG are still part of the public API in 3.X and then 
suggest alterations to documentation based on that.