Hi Lucene community,
We've identified a significant performance regression in Amazon when upgrading to JDK 25 that affects applications using Parallel GC Issue: JDK-8375467 - Unproductive Full GC cycles with Compact Object Headers enabled • Link: https://bugs.openjdk.org/browse/JDK-8375467 • Affects: JDK 25 with Parallel GC + Compact Object Headers Our Experience: We observed heap usage spiking to 100%, dramatically slower indexing, and much larger segment merges in production. Root Cause: The new Parallel GC implementation for Lilliput (Compact Object Headers) has a bug where non-maximum-compaction full GCs become unproductive, leading to repeated unproductive GC cycles. The OpenJDK team is working on a fix. Best regards, Rohith Reddy Nedhunuri
