The least recently used taxonomy threshold property indicates the maximum time that can elapse since a taxonomy was last accessed before it is unloaded. In the properties file, this property is named taxonomy_cache_threshold.
Settings for this property include:
Value—In minutes.
Default—The default value is 30 minutes. For example, setting the value to 30 means that a loaded taxonomy remains in the cache (memory) for up to 30 minutes of inactivity before it is unloaded. When a new user request, which accesses a taxonomy occurs, its time stamp is reset. In this example, 30 minutes of no user requests must occur before the taxonomy is unloaded.
Disable—Setting the value to zero disables this feature.