in reply to shared memory LRU cache which containes filehandles
I agree with lhoward's answer. Surely its time to think of SQL and a relational database (MySQL etc). I also disagree that the free databases are little better than tied hashes. MySQL has a very good reputation. In fact IMHO, if your database has under 1000 tables and key table contain less than a million rows then no commercial product is worth buying. (specially Oracle :-)