Re: Major performance problems with Informix Online

On Mon, 20 Oct 1997 07:21:54 -0400, Tim Schaefer <tschaefe@mindspring.com> wrote: >I <was> curious to some of the tuning information, were these recommendations >purely for a Siemens machine or were these for 7.2x in general? > >A couple of the recommendations were interesting ( yes experience here ) and >I want to know a little more reasoning, if you can elaborate. I'm in learning >mode here. :-) > >Questions about the responses ( Koens and Davids ): > >1. The logging information was a bit confusing. ??? >2. NUMCPUVPS looked ok, even low, I've heard use (CPUs - 1) as the rule? If your computer have something else to do except to run the database you should leave some procesors for that. If you are binding CPU_VP-s on procesors you must leave at least one procesor to run OS. If your database server is used only for that porpose, or have wery litle other jobs you can put NUMCPUVPS=_num_of_CPUs_ , and without affinity. If you have only two or three CPUs you can try this even with computer running DB and some other serious jobs. >3. NOAGE and affinity can cause problems on some systems, I'd turn them on last. They are not supported on some systems, as well as RESIDENT. >4. I wouldn't diddle with PHYSBUF OR LOGSBUF sizes. Why would you change these? No comment. >5. Using OSTIME, and using the system instead of internal. Does this apply to > other machines? You should use OSTIME only when you need fraction of a second. (Try to check this somewhere else too.) >6. RA_PAGES. What's your theory here? :-) The command "onstat -p" can give you some interesting numbers in the last row. If RA-pgused / (ixda-RA + idx-RA + da-RA ) is not high enough you should use lower values for RA_PAGES and RA_TRESHOLD. >7. OPCOMPIND is ok to use with 7.2x?? I heard this was a showstopper. ??? Ivica Smolic Chief of computer maintenance (or something like that) Company Address: Medimurska banka Valenta Morandinija 37 40000 Cakovec Croatia tel.: 385 40 810638 fax.: 385 40 810623 E-mail: ismolic@open.hr