Read-aheads and bufwaits

IDS: 7.30.uc7 OS: HPUX 10.20 KAIO: enabled and working well While testing RA parameters, I noticed that when read-aheads weren't activated ( set to 0 in ONCONFIG ), I had no bufwaits. When I activate them (64 / 32), the bufwait count increases. While rereading my notes, I thought that the two sets of parameters were unrelated. Is there something different about 7.30 that ties the two together? NOTE: This is the only application active on the test system. John Carlson Informix DBA WHSmith USA

Carlson@WHSmith wrote: > > IDS: 7.30.uc7 > OS: HPUX 10.20 > KAIO: enabled and working well > > While testing RA parameters, I noticed that when read-aheads weren't > activated ( set to 0 in ONCONFIG ), I had no bufwaits. When I activate > them (64 / 32), the bufwait count increases. > > While rereading my notes, I thought that the two sets of parameters were > unrelated. Is there something different about 7.30 that ties the two > together? NOTE: This is the only application active on the test > system. Increased buffer activity related to the extra reads all close together from the readahead. Perhaps you need to increase the number of LRUs. That often helps reduce bufwaits (avoid 64 & 96 though). Art S. Kagel