- SYSTEMS Programmer > 25 years
- Installation/Capacity Planning/Performance > 15 years
- Disaster Recovery > 20 years
- DB2 V. 5 up to V10 - 15 year
- Z/OS > 25 years
- CICS > 15 years
- WORKLOAD MANAGER,
- Coupling Facility,
- MAINVIEW and several other CA,
- BMC & RESPONSIVE SYSTEMS tools
PROFESSIONAL EXPERIENCESr. DB2 Systems Programmer
- Responsible for DB2 system tuning of over 190 subsystems spread throughout the Confidential.
- DB2 installation, Capacity Planning, System Performance and Disaster Recovery
- Led/assisted in several DB2 migrations; from V6 until the latest V10, as well as applied maintenance across multiple DB2 versions.
- The production environment consisted of Data Sharing groups of several sizes; from a few 3-way to several 12-way Data Sharing groups spread throughout the Confidential .
- Assisted in the redesign/consolidation strategies of LPARs in a sysplex data sharing environment.
- Worked closely with z/OS specialists to design WLM policies and insure that enclaves from different DB2 workloads had classifications according to their SLAs.
- Worked closely with z/OS specialists in problem determination analysis of CPU and DASD delays. Specialty engines DB2 usage was monitored closely across all lpars.
- Designed and maintained local & group buffer pools of all production Data-sharing environments.
- Buffer pools were set according to the different characteristics of the workloads. Analyzed local pools’ behavior and page fixed I/O intense buffer pools.
- Worked with DBA team to identify rogue workloads which had intense tablespace scans. Page residency time was used to size local pools. This insured a minimum consumption of virtual storage while providing a robust pool configuration. This strategy took into account the ability of surviving members to absorb the workload of a failed subsystem.
- Group buffer pools were sized to avoid cross-invalidations due to directory reclaims. GBPs synchronous hit ratios were monitored closely.
- GBP’s internal thresholds were adjusted to provide a trickle writing effect.
- Lead the resolution process of complex database systems problems where analysis of situations or data requires an in-depth evaluation of various factors.
- Reviewed and updated zparms across different DB2 versions with the objective of tuning systems.
- Pseudo-closing was monitored constantly to avoid high number of latch counters and unnecessary messages sent to the Coupling Facility, thus avoiding CF overhead. This provided a faster throughput for batch workloads.
- Package authorization cache and caching routine authorization high misses rates were corrected by adjusting CACHERAC and CACHEPAC values.
- Implemented a DB2PM Statistics Performance Database to be used for trend reports and problem determination.
- Several SQL queries were automated to help identify possible performance issues.
- Implemented a DB2PM Accounting Performance database to be loaded only for problem determination reasons.
- Lead and participate in the design, development, and implementation Bank of America’s DB2 Disaster Recovery strategy.
- Sized DB2 pools in large Data Sharing group to allow surviving members to absorb the workload of failing members.
- Provided guidance on DB2 system performance on a large SAP/DB2 configuration
- Worked with SAP Basis Administrators to adjust DB2 internal parameters to accommodate the workload
- Used page residency time to size local pools properly
- Monitored group buffer pools to avoid cross-invalidation and maintain a high synchronous hit ratios
- Interfaced with MVS Systems programmers to design WLM policies
- Assisted on LPAR, number of processors and weights configuration
- Lead migration from OS/390 DB2 V6 to V7
- Applied DB2 maintenance