Humongous allocation full GC
A Java service running G1GC has fine average GC behavior but develops periodic ~1.5s full-GC pauses (not normal young/mixed pauses) that cause request timeouts a few times an hour. Heap usage looks moderate (~55% of 16GB) and there's no obvious memory leak (heap returns to baseline after each pause). GC logs show frequent 'humongous allocation' entries and a rising humongous-region count, plus occasional 'to-space exhausted.' A week ago a feature began returning larger result payloads (some multi-MB byte arrays / lists). How do you triage and mitigate?
What a strong answer looks like
Stop the bleeding first (mitigate), then form hypotheses from real signals. Separate root cause from symptom, communicate status as you go, and close with what prevents a repeat.
0:00 of about 35 min
Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.
Run or narrate your approach, then ask the coach.