A report services document Cache will be marked as invalid and cleaned up if any of the following criteria are met:
When a document cache is invalidated, an entry similar to the following will be seen in the document server cache trace:
RWDCache Manager: cache with ID A2BC507A4BA2034A02A7E68DFE194966 is deleted
RWDCache Pool Table: cache with ID A2BC507A4BA2034A02A7E68DFE194966 is removed
Backup cache index C:\Program Files (x86)\MicroStrategy\Intelligence Server\Caches\Strategy Analytics Modules Server\MyServer\RWDCache\RWDPool3.idx.