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Subscriber LoginCheryl Watson's Tuning LetterFor more than 30 years, Cheryl Watson’s Tuning Letter has been the premier source of mainframe performance tuning insights. Renowned for its in-depth analysis and expert guidance, the Tuning Letter helps thousands of...

Arcati 2026 – Get InvolvedOur planned 2026 release for theArcati Mainframe Navigator is February 2026.Complete the 2026 Arcati Mainframe User Survey — Get a $10 Gift! For the next 100 verified respondents, we’re offering a $10 thank-you gift for completing the survey....

Subscriber LoginCheryl Watson's Tuning Letter | ArchivesExplore more than 30 years of Cheryl Waton's Tuning Letter content. Issue 01 Downloads Management Summary Cheryl's List SHARE Conference Recovery at Scale - Part 3 (Ransomware) User Experiences and Tips...

Subscriber LoginMost Recently Published Tuning LettersWhat's in this Issue GS-UK In-Person Conferences by Mark Wilson A Coffee Date with Db2 by Sally Mir Using Cloud Object Storage by John Hogan CICS 6.35 by Mark Wilson Unlocking business insights by Steve Warren...

Subscriber LoginCPU Chartsz Systems – Updated for May 2025 Presented in PDF and Excel format Cheryl Watson’s z Systems CPU Chart provides a comprehensive list of 3,147 processor configurations from IBM that can run z/OS. This current version contains the most recent...

Subscriber LoginLatest CPU ChartsMay 2025 IBM Z CPU Chart (This chart is based on z/OS 3.1 LSPRs and includes the 337 new IBM z17 processors that were announced on April 8, 2025.) Below you will find the spreadsheet for the CPU Chart for the z17. The first chart...

Subscriber LoginPresentations & MorePresentations & Papers This section contains our slide presentations [S] and papers [P] from user conferences such as SHARE, CMG, and IBM Conferences, as well as technical magazines, such as Technical Support Magazine and...