Cheryl Watson’s Tuning Letter
For 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 organizations optimize their z/OS and MVS environments, cutting through complexity with practical, field-tested advice.
As technology and workloads have evolved, so has the Tuning Letter. Through it, readers say they:
- Gain the tools to bridge the mainframe skills gap
- Stay ahead of rapid hardware and OS changes
- Tap into a gold-standard reference library when troubleshooting
- Eliminate vendor noise
- Learn new tuning strategies that drive measurable cost savings
Every article, presentation, and tip is designed to help solve problems faster and keep your systems running at peak performance.
Join the thousands of mainframers worldwide who rely on the Tuning Letter.
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Current Issues
Access the current 4 issues of the Cheryl Watson’s Tuning Letter.
Tuning Letter Archives
Dig into the Cheryl Watson’s Tuning Letter archive, going all the way back to 1991.
CPU Charts
Access the CPU Charts to help with measuring performance and estimating pricing models.
Presentations & More
Technical presentations, published articles, and more.

