Cache Management

Because network connections are expensive in time, compute cycles and network bandwidth, a strong caching paradigm (love using that word) was implemented to help lower the use of resources and lower the response time.

Configuration

• the timeout and size can be tweaked as needed to support a particular environment. The system will send out an INFO alert if it's purging too quickly.
• the memory cache can be completely disabled by setting the size to 0. This should only be done if you are using a single process, as the database interface *should* be caching results.

Lookups

• Each search to the AD server is through a cached LDAP filehandle. The restart option has been enabled to allow it to persist.
• When valid data is found .. the data is pickled, and the key hashed and stored in a new table in the database called ad_cache.
• It's also stored in a class variable _cache which is a dictionary.

Retrieval

• the memory cache is checked first
• then the database cache
• lastly the AD server itself is searched
• Any results are then pushed back on the cache(s)

Integration

• data is cached by 'class' where appropriate to speed up processing,
• all ldap searches are cached using a key which is a hashed combination of ( base_dn, scope, filter )