Sascha, This rule is for UNIX servers (AIX, Solaris, HP-UX). You can find where the rule originates from - in redbook "Getting Started with Tivoli Storage Manager: Implementation Guide" (SG24-5416-01) on p.270 you can find a description "Tivoli Adaptive Algorithm: Tivoli Storage Manager can use the SELFTUNEBUFPOOLSIZE YES parameter in the server options file to activate self-tuning. When you activate this option, the server will check the cache hit ratio each time inventory expiration is run. If the value is less than 98%, then it will increase the BUFPOOLSIZE by a predictable factor related to the actual cache hit ratio achieved. An upper limit for BUFPOOLSIZE with self-tuning is imposed of 10% of the real memory for AIX, HP UX, Sun Solaris and Windows NT, and 50% of the region size in OS/390. If you still need a larger BUFPOOLSIZE and it is acceptable in your environment, you will have to set the value manually."
And because your question was about OS/390 TSM servers the correct answer ought to be 50% of the TSM server region. If 49152k is 10% of the region size then the correct answer probably is 245760k. Of course if 49152 is 10% of total memory of the mainframe then the region is smaller and bufpoolsize must be too. In fact you are achieving 97.7% with only 32 MB so 48 MB might be enough to get over 98%. Many people on this list reported that SELFTUNEBUFPOOLSIZE served them well and it might be worth to try it yourself. Zlatko Krastev IT Consultant Please respond to "ADSM: Dist Stor Manager" <[EMAIL PROTECTED]> Sent by: "ADSM: Dist Stor Manager" <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] cc: Subject: Antwort: Re: cache hit rate Hi, an IBM Technician gave me the following rule: bufpoolsize = 10% of your memory. I think 49152 is ok ... 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]
