On-Line Perform. on RS6000

Good morning, from the finally warming up Northeast! We have been running INFORMIX On-Line (now vers. 5.01) on an IBM RS6000 Model 930 for almost 4 years. We have been disappointed with the performance from the beginning and have sought the advice of both IBM and INFORMIX supplied consultants. None have been able to identify and resolve our problems. I have noticed that immediately after we reboot the system, and with only 1 individual logged in, anything run in INFORMIX completes very quickly. As an example, we have a 2.5 million row, 850MB database. If we do a select (*) from the db, and dump the results to /dev/null, we can read through the file in about 40 minutes. But, after the system has been up and running, and with other users logged in, performance degrades to, at best, 2-3 hours for the same select, and at worst, can take 6-8 hours. I realize that with a single processor machine, load is not handled well, and some degradation occurs, but am wondering if there are "hidden or invisible" things, like daemons, memory eaters, cpu hogs, processes hung and still running, or other things that might be causing our extreme degradation. We use both IBM bundled utilities and tbcheck and can't "see" anything. Any ideas, suggestions? Thanks. ========================================================== lmarks@hanys.org Louise Marks Healthcare Association of NYS