Fix for Issue Where Session-Wise PGA Usage Aggregates Differ from Actual Values

Issue Number	701306a
Issue	Despite no actual memory shortage occurring, excessive memory demand warnings are heavily logged in the system logs. Additionally, session-wise and overall PGA usage figures in views such as V$PGASTAT and V$SESSION may be displayed inaccurately compared to actual usage. After the PE process restarts, the PGA usage of the PE CTHR is not reset and retains previous values.
Cause	During the aggregation of session-wise PGA usage, shared memory allocator usage data is updated without concurrency protection, which can lead to data loss if multiple threads update simultaneously. Also, the process cleanup path lacks the usage reset logic for specific threads.
Solutions	Apply atomic operations to ensure data integrity when aggregating SYSTEM_ALLOC usage. Limit the frequency of warning logs to prevent unlimited generation even when thresholds are exceeded. Reset PGA usage during PE process cleanup.
Occurrence Date	August 21, 2026
Versions Requiring Patch	6FS07PS 7FS02PS

Patch Name	FS02PS_701306a
Major Version	7
Minor Version	FS02PS
Version Title	Fix for Issue Where Session-Wise PGA Usage Aggregates Differ from Actual Values
Release Date	September 4, 2026
Compatibility	• TAC Rolling Patch: Supported • TSC Rolling Patch: Supported • Backup Data Compatibility: Supported • Protocol Compatibility: Supported • Data Format Compatibility: Supported
AP Impact	• Plan Changes: No • Result Value Changes: No • SQL Syntax Changes: No • System Object Changes: No • Existing Feature Changes: No
Parameters	-
Workaround	Disable _SYSTEMALLOC_CONSUMPTION_CHECK parameter SQL> ALTER SYSTEM SET _SYSTEMALLOC_CONSUMPTION_CHECK = N;

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