WordCacheSize defines the maximum allowed size of the in-memory words cache.
Word cache is used with DBMode=multi to improve
crawling performance.
A separate word cache of the given size is allocated for every DBAddr command, so if indexer.conf contains three DBAddr commands with WordCacheSize set to 10Mb, then 30Mb of RAM total will be used for the three word caches.
The default value is 8388608 (8Mb).