Buffer sizing

I've been reading the Performance and Tuning manual and have some questions regarding the amount of buffers to use. I'm running ODS 7.22 on a system with a Gig of memory and a 4K page size. According to the manual on page 2-29, it says that buffers should be set between 20-25% of physical memory. Ours is currently set at 15,000 which is low according to the recommendation. Our read/write buffer utilization is 95+% and 90+% respectively which would seem to indicate the we do not need the excess buffers. However, bufwaits continues to climb (it's about 1.15% of the read + write pages total) and we occassionaly have foreground writes (right now there have been 2 today). I have 19 dbspaces, 1 chunk per space, running kaio, 25 LRUs, 18 cleaners and min/max dirty set at 7 and 3 so we're flushing almost constantly (currently 72.8% of writing is being done by the cleaners in non-checkpoint times). Checkpoint duration is at 5 minutes and run usually between 1-3 seconds. The disks/controller doesn't seem to be saturated yet so it doesn't appear the bottleneck is there. Why is bufwaits climbing and why do I get these foreground writes when it appears that plenty of buffers are available? Do I need to up buffers to the recommended levels? Do I need more lrus or cleaners? Am I missing something? Do I really even have a problem? By the way, we run a separate instance of Informix on this box also. However, it is for development so it is very scaled down in terms of the resources allocated to it. There are no other applications running on the box. -------------------------------------------------------- Name: Bill Weaver E-mail: Bill Weaver <billw@fscorp.com> Date: 10/20/97 Time: 14:20:30 This message was sent by Z-Mail Pro - from NetManage NetManage - delivers Standards Based IntraNet Solutions --------------------------------------------------------