Re: Database tuning.. any hints?

jockc (jockc@netcom.com) wrote: : I'm very new to Informix and I'm trying to improve performance : for an Informix application we are running. The application is : Quintus and each process is consuming about 10 megs of virtual : memory on an HP 9000 server. Of the 10 megs about 6meg is private : data. Also the tbstat -p program reports about a 95-97% cache : hit rate on reads but less than 20% on writes.. I have BUFFERS : set at 1000, LOCKS is about the same, and the clean MIN/MAX values : (can't remember the parameter names) are 70 and 80.. I've made a : few changes as suggested by the ref manual tuning section and gotten : some improvement. Can anyone suggest anything I can do. Do I : need to provide more info about my tbconfig settings? You need *loads* more buffers. It sounds like your application is performing many updates. You don't mention what your checkpoint interval is set to but if it is around five minutes, try setting your number of buffers to something like 10,000 and see how long checkpoints take. If they take an unacceptably long time, then start reducing MIN_DIRTY, MAX_DIRTY so that most writes are LRU writes, and the checkpoint time is acceptable. The number of locks that you need depends totally on your application. If you don't run out of locks then leave the figure as it is. Mike.