Hi Team,
I’ve been working on a project that involves periodic load testing using Grafana K6. On several occasions, I’ve observed that the database becomes unavailable during testing, even though CPU, RAM, and active connections remain well below their limits or saturation points.
From the logs, it appears that PostgreSQL restarts unexpectedly without any preceding errors or resource constraints. Unfortunately, I haven’t been able to locate any related logs that indicate why it restarted. Could you please help me understand this behavior? it happens almost all the time when I do load test.
Based on the available logs, this doesn’t seem to be caused by lock contention or performance degradation. However, I do see clear entries indicating that the database system was “interrupted” and then “starting up,” as shown below:
[6905b181.44-1] user=,db=,app=,client=,LOG: database system was interrupted; last known up at 2025-11-01 07:05:20 UTC
[6905b181.45-1] user=[unknown],db=[unknown],app=[unknown],client=*.*.*.*,LOG: connection received: host=*.*.*.* port=53998
[6905b181.45-2] user=psql_db1,db=psql_db1_bj6f,app=[unknown],client=*.*.*.*,FATAL: the database system is starting up