Use the PGA Memory Pressure alert in Mini DBA to monitor Oracle instances and make this condition visible before it becomes a wider database incident.
Mini DBA describes this alert as: PGA (Program Global Area) memory usage vs target When PGA exceeds target, operations spill to temp tablespace Consider increasing pga_aggregate_target parameter The default evaluation frequency is Minute, so the alert is intended to be close enough to operational reality for live triage. Because duration is used, Mini DBA can avoid treating a single short spike as a full incident when the condition clears quickly.
This alert helps detect memory pressure and cache efficiency problems. Low cache effectiveness or high memory pressure increases physical I/O, query latency, and the chance that a workload will become unstable during busy periods.
Enable it once the instance has a normal workload baseline. It is especially useful on busy OLTP, reporting, and integration systems where resource pressure can quickly become user-visible.
Threshold meaning: % of target. Major threshold: 98 %. Minor threshold: 95 %. Comparison direction: "over". Duration is used, so prefer requiring the condition to persist before paging people for transient spikes. Use higher thresholds on batch-heavy, development, or intentionally bursty systems where brief pressure is expected. Use lower thresholds on latency-sensitive production systems, small instances with little headroom, and services with strict recovery or availability commitments.
Check memory configuration, cache hit indicators, top memory consumers, and host pressure. Remove unnecessary competing services, tune query memory grants or work areas, adjust engine memory settings, and add RAM or resize the service tier when the working set has outgrown the instance.
If this alert is noisy, check whether the workload naturally has short bursts. Raise the duration or threshold for expected batch windows, but keep a lower route for production systems where user-facing latency matters. Avoid simply disabling the alert until you know whether the noise is caused by threshold choice or by a real capacity trend.