Data Monitoring / PostgreSQL Monitoring
PostgreSQL: Temporary file growth
Large analytical queries spill substantial work to temporary files. Compare temp byte deltas, query evidence and concurrency for the incident window.
Environment and inputs: PostgreSQL 18 documentation baseline; views, extensions and permissions vary across versions and managed services.
Failure scenario
Large analytical queries spill substantial work to temporary files. Confirm the cause before choosing a fix.
Evidence to collect
Compare temp byte deltas, query evidence and concurrency for the incident window. Record the time, affected scope and a healthy comparison interval.
Fix the confirmed cause
Reduce expensive sort or hash demand and test memory changes with total concurrency in mind. Write the expected result first. Change one relevant setting at a time.
Check the result and hand over
Repeat the check for temporary file growth using the same scope and a representative interval. Check that the symptom is resolved, expected records are present and downstream results are correct. If coverage, correctness or latency worsens, restore the recorded configuration through the agreed rollback process.
Scope and precautions
Prefer read-only access and limit queries to the relevant period or dataset. This example has not been tested on your systems. Test changes in an approved environment. Keep credentials and sensitive data out of shared evidence.