Re: Kernel Asynchronous IO on HP-UX

KAIO on HP-UX can bring a good performance increase (~10%) or, under certain conditions, can result in a severe (30-100%) decrease in disk IO speed. Informix and HP continually tweak their respective code lines to get the most out of each system, which sometimes results in issues like this. For example, Informix changed the way the "select ()" and the "nanosleep ()" calls worked from version 7.1 to 7.2 to 7.3 at the same time that HP changed the way these calls are implemented in the o/s. Your best plan is to read the release notes and machine notes for Informix and HP, use the very latest versions of each that you can, and then to verify for yourself how the feature runs in your environment. Be cautious about general statements and anecdotes. One of the nice things about KAIO is that it is pretty easy to turn on and off. HTH, Clem At 02:37 PM 01-10-98 GMT, Douglas Agnew wrote: >We were using 7.21 on HPUX 10.20 and were told NOT to use KAIO. Seems it works, >but not well. At 7.23, I don't know what the situation is, but it may require >changes from HP to resolve. > >EsquivelR wrote: > >> I have two Unix servers which run Online 7.23.UC7 and Online 7.14.UD6. Both >> servers are running HP-UX 10.20. Has anyone out there had any experience using >> Kernel Asynchronous IO? I'm looking for any known "gotchas" or testimonials on >> increased performance. >> >> esquivelr@aol.com > > > > > _____________________________________________________________ Clem Akins (aka clem@informix.com) Menlo Park x5937 Customer Course Development Informix Software, Inc Last seen: Pondering weak and weary over many quaint and curious volume of Informix lore...