Here, you can configure the cache size in KB (geomsearch.cfg)

[CACHE_GEODB]
#:VALS_N
#:HELP;Kilobytes that geo db tables may consume
TableCacheSize=500000

As of SP3, you can find out how much memory is needed for the caches using this command:

geoDbUtils.exe cachesize *

This is the result of the current call and will change when adding new parts.