JSAM - Job Summary Analysis Monitor

Enhanced Definition

JSAM (Job Summary Analysis Monitor) is a utility or software product designed for the IBM z/OS environment to monitor, analyze, and report on the execution characteristics of batch jobs. Its primary purpose is to provide insights into job performance, resource consumption, and completion status, aiding in performance tuning and problem determination.

Key Characteristics

- Data Source: Primarily collects execution data from System Management Facilities (SMF) records (e.g., Type 30 for common address space work, Type 42 for dataset activity) generated by z/OS.
- Reporting Capabilities: Generates various reports including summary reports, detailed job step reports, exception reports (e.g., long-running jobs, high CPU usage), and trend analysis reports.
- Performance Metrics: Tracks key performance indicators such as CPU time, elapsed time, I/O counts (EXCPs), memory usage, and abend codes for individual jobs and job steps.
- Historical Data Management: Stores collected job execution data in a database or flat files, enabling historical analysis, trending, and capacity planning.
- Alerting and Notification: Can be configured to issue alerts or notifications when predefined thresholds are exceeded (e.g., job runtime exceeding SLA, excessive resource consumption).
- User Interface: Typically provides a user-friendly interface, often ISPF-based or a web-based dashboard, for querying data and viewing reports.

Use Cases

- Batch Performance Tuning: Identifying specific jobs or job steps that consume excessive CPU, I/O, or elapsed time, allowing developers and system programmers to optimize COBOL programs or JCL definitions.
- Problem Determination: Quickly pinpointing the root cause of batch window overruns, job failures (abends), or performance degradation by analyzing historical and current job execution data.
- Capacity Planning: Utilizing historical resource consumption trends to forecast future hardware and software requirements for the batch workload.
- Service Level Agreement (SLA) Compliance: Monitoring job completion times against defined SLAs to ensure critical business processes are completed within expected windows.
- Chargeback/Showback: Providing detailed resource usage data for attributing costs to specific applications, departments, or business units based on their batch workload.

Related Concepts

JSAM relies heavily on SMF (System Management Facilities) as its fundamental data source, processing the raw SMF records into meaningful performance metrics. It complements Job Schedulers (like IBM Z Workload Scheduler / TWS, CA-7, BMC Control-M) by providing post-execution analysis that schedulers typically don't offer. While RMF (Resource Measurement Facility) and other system-level monitors (e.g., IBM OMEGAMON) provide broad system performance data, JSAM offers a more granular, job -centric view. It helps validate the effectiveness of WLM (Workload Manager) policies by showing how individual jobs perform under their assigned service classes.

Best Practices:

Regular Report Review: Periodically review JSAM summary and exception reports to proactively identify potential performance bottlenecks or inefficient JCL/COBOL code.
Define Meaningful Thresholds: Configure alerts with realistic thresholds for job runtime, CPU usage, and I/O counts to focus on critical issues and avoid alert fatigue.
Maintain Sufficient Historical Data: Retain several months or even years of historical job data to enable robust trend analysis and accurate capacity planning.
Integrate with Automation: Where possible, integrate JSAM alerts with automated operations tools to trigger actions like notifying support teams or initiating recovery procedures for critical job failures.
Collaborate with Development: Share JSAM insights and performance data with application development teams to foster a continuous improvement cycle for batch application efficiency.