Re: Database tuning.. any hints?

Don't worry too much about the write caching rate. Although the book says that you should aim for 80% this assumes a well-balanced application. If you are doing a large number of INSERTs of large record sizes you will probably not achieve very high caching rates. Think about the application. Do you think that it is running slow? Try to understand why this would be. If you do a large amount of browsing between updates this could also cause the write caching to be low. I personally would query the amount of private data for the applications. And is Shared Memory Resident? if not it might be swapped! And that would certainly affect performance. Have you attended an INFORMIX OnLine Admin course? They are worth doing. Malcolm Weallans ONLINE Database Consultancy (+44)628-72154