On woensdag, augustus 21, 2002, at 09:46 , Sascha Braeuning wrote: > Hi all, > > first I've to thank all participants for the amount of answers I got on > my > latest questions. Now I've got a new one which relates on the > bufferpoolsize and the cache hit rate on OS/390 TSM-Servers. > > we use the following bufpoolsize: 32768 > our chache hit rate: 97,7 % > > I know from my training at IBM that a cache hit rate of 99 % and above > is > recommended. Is it possible, that a lower cache hit rate can cause > performance-problems? What is your experience? > > > MfG > Sascha Br�uning > > > Sparkassen Informatik, Fellbach > > OrgEinheit: 6322 > Wilhelm-Pfitzer Str. 1 > 70736 Fellbach > > Telefon: (0711) 5722-2144 > Telefax: (0711) 5722-1630 > > Mailadr.: [EMAIL PROTECTED] >
Hi, a too low cache-hit rate has severe impact on performance. I guess 98% cache-hits or better is acceptable. Set the selftunebufsize in your dsmserv.opt file to allow TSM to tune the size of its cache for better performance (though i noticed setting it to more or less a sensible default to start with helps a lot...) --- Met vriendelijke groeten, Remco Post SARA - Stichting Academisch Rekencentrum Amsterdam http://www.sara.nl High Performance Computing Tel. +31 20 592 8008 Fax. +31 20 668 3167 "I really didn't foresee the Internet. But then, neither did the computer industry. Not that that tells us very much of course - the computer industry didn't even foresee that the century was going to end." -- Douglas Adams
