RA, bugs, and performance

Informix DS 7.23.uc4 HPUX 10.01 HP K200 4-way Up to this time, I have maintained a RA hit percentage of 90-99%. My RA variables were set to : RA_PAGES 150 RA_THRESHOLD 75 While these numbers were a bit high, we were able to take advantage of most of the pages that were read-ahead. As part of my tuning, I was planning to revisit these variables. Where would be a good trade-off between read-aheads and bufwaits? I've seen the postings by various people, and took them to heart for the next round of R&D testing on my test system. Unfortunately, bug# 85350 changed all of that. I now have reset these parameters to 0. While I didn't mind retuning these variables, I hadn't planned on resetting them quite like this. Any idea of what the impact to my system would be? We're a mixed environment, OLTP and DSS batch reporting.