condensediffs had some memory issues. Even though we were using

QuerySet.iterator, it seems memory was still increasing far too much.
To work around this, we're using a couple tricks that we used in

loaddb and dumpdb. We're only operating on batches of 200 diffs at a

time, and are resetting queries and garbage-collecting after each batch.
The query resets shouldn't impact production installs, since DEBUG

should be False, but it's a precaution. We're also forcing DEBUG to be

False in the management command as well.
With these changes, memory still increases over time, to a degree, but

seems to stabilize. This is with a sample set of over 8200 diffs.

Added some debug information to check process memory usage before and after.
Before, memory was steadily rising in usage (even with DEBUG = False).
After, memory rose for a bit and then stayed pretty steady, without growing

unexpectedly large.