Frequency
In the context of IBM z/OS and mainframe systems, **frequency** refers to the rate at which specific events, transactions, or operations occur within a given timeframe. It is a critical metric used for performance analysis, capacity planning, problem determination, and system monitoring, indicating how often an activity takes place.
Key Characteristics
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- Context-Dependent: The meaning and significance of frequency are entirely dependent on the event being measured (e.g., CICS transaction frequency, I/O request frequency, error message frequency).
- Time-Bound: Always expressed as occurrences per unit of time (e.g., transactions per second, jobs per hour, errors per minute), providing a quantifiable measure of activity.
- Performance Indicator: High or low frequencies of certain events can indicate system health, bottlenecks, unusual activity, or workload intensity.
- Data Source Driven: Frequencies are derived from system logs like
SMF (System Management Facilities),RMF (Resource Measurement Facility),SYSLOG, application logs, and various mainframe monitoring tools. - Baseline Comparison: Often compared against historical baselines or expected values to detect deviations that might signal performance issues, security threats, or operational anomalies.
Use Cases
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- Performance Monitoring: Tracking the frequency of
CICStransactions,DB2calls, orIMSmessages to ensure service level agreements (SLAs) are met and identify peak usage times. - Capacity Planning: Analyzing the frequency of batch job executions, online user logins, or specific resource requests over time to predict future resource requirements and plan upgrades.
- Problem Determination: Identifying an unusual spike in the frequency of
abends, error messages (e.g.,WTOs), or resource contention events to pinpoint and diagnose system issues. - Workload Management (WLM) Optimization: Using frequency data to refine
WLMpolicies by understanding the distribution and intensity of different workloads, ensuring critical tasks receive appropriate resources. - Security Auditing: Monitoring the frequency of failed login attempts, unauthorized access attempts, or specific security events to detect potential breaches or policy violations.
- Performance Monitoring: Tracking the frequency of
Related Concepts
Frequency is a fundamental metric derived from and applied to various z/OS components. It is often analyzed in conjunction with response time to understand overall system performance, as a high frequency of slow transactions indicates a major bottleneck. It relies heavily on SMF (System Management Facilities) and RMF (Resource Measurement Facility) data, which capture the raw event records from which frequencies are calculated. Effective Workload Management (WLM) policies are often based on understanding the frequency and importance of different workloads to prioritize system resources.
- **Establish Bas
The term "Frequent - Often occurring" is a general English adjective and not a specific technical term within the IBM mainframe, z/OS, COBOL, or JCL ecosystem.
This glossary is designed for technical terms unique to or having a specific meaning within the mainframe context. As "frequent" does not have a specialized or distinct technical definition, implementation, or usage within z/OS beyond its standard English meaning, it cannot be given a meaningful entry following the specified structure.
Please provide a technical term relevant to mainframe/z/OS technologies for which to generate a glossary entry.