The leak that isn't on the heap

Reported: ingestd RSS goes 300MB → 1.4GB over 4 weeks, then the OOM killer takes it. Heap usage (jstat, heap dumps) holds flat at ~90MB, with no GC pressure.

• This month's release added a zero-copy parser that does ByteBuffer.allocateDirect(64 * 1024) per message and lets it drop after parsing (~3k msg/s).
• -XX:MaxDirectMemorySize unset.
• jcmd <pid> VM.native_memory summary (NMT enabled on canary):

- Internal (reserved=1210MB, committed=1190MB)
     (malloc=1188MB #4,019,551)

• Container base image uses glibc malloc with default MALLOC_ARENA_MAX.