Modules like GDBM_File are fraught when you have potentialy many readers/writers (like say in a long running forking daemon). While they might handle file locking properly, if any program holds the lock for too long, others will not be able to write to the file. This module solves the problem by doing a tie/operation/untie for each and every operation. NOTE THAT THIS IS ONE HUGE PERFORMANCE HIT. Only use this where all other methods fail.