Re: Reducing Extents on Informix 5.0 and hp-ux

Yes indeed. I am sure there are tons of others who are doing it day-in and day-out. Well your check list should include the followings (and may be more depending on the seriousness of your slow-downs): a) Check to see if you are using proper indexes on all queries. b) Check to see if you have spread-out your tables across multiple hard drives. c) Check to see if your tables are normalized and contain a manageable record lay-out. d) Check to see if you are using proper LOCK MODEs on all tables, and adequate WAIT times for responses from the engine. e) Check to see if you are using proper EXTENT SIZES for each table. Reducing EXTENT sizes will increase the number of EXTENTS used by a table and will certainly affect the performance adversely. There is a danger of you running out of max extents parameter. f) Check to see if your code is optimized and ensure that it is designed to avoiding all unnecessary SQL related over-heads. (80% of gains in performance is achievable by tuning your code - not tweeking the database! Believe me. It is a reality!! The more you clean-up the more you will be left with to clean-up!!!) g) And finally, you may have to look deeper into your processing logic to find places where you can intercept the flow at logical intervals and perform summarization activities (Extra Work ???) . You may consider that it is ill-logical but it has been found to be more than practical. This little extra work leads to better utilization of the CPU as and when it is available and reduces a lot of work for the database at a later point in time. Regards, Ravi.