sqlite: fast path when nothing to save If we have no new data to save, we should try to do anything. Doing something concurrently is hard enough. If we can avoid doing it at all that would be great.

sqlcache: initialize meta table last It turns out that pysqlite commit after each table creation. This commit is an hopeless attemps to make the caches more concurrent friendly.

obshashrange: always check in base cachekey against the recorded one Ignoring the check in the none case is just disaster waiting to happens.