Allocate one large segment and slice for each MsgHdrMemory (#16234)#16251
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normanmaurer merged 1 commit into5.0from Feb 11, 2026
Merged
Allocate one large segment and slice for each MsgHdrMemory (#16234)#16251normanmaurer merged 1 commit into5.0from
normanmaurer merged 1 commit into5.0from
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Motivation: IoUringIoHandler.msgHdrMemoryArray has 1024 MsgHdrMemory instances, each allocating 4 CleanableDirectBuffers. On JDK 25, each clean() closes a shared Arena, so shutdown performs 1024 * 4 closeScope0 calls, i.e., excessive handshakes. Modification: Reimplement MsgHdrMemoryArray to allocate one large segment and slice for each MsgHdrMemory. collapses 4096 shared closes into a single close. Result: Fixes #16174 --------- Co-authored-by: Norman Maurer <norman_maurer@apple.com> Co-authored-by: Chris Vest <christianvest_hansen@apple.com>
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Motivation:
IoUringIoHandler.msgHdrMemoryArray has 1024 MsgHdrMemory instances, each allocating 4 CleanableDirectBuffers. On JDK 25, each clean() closes a shared Arena, so shutdown performs 1024 * 4 closeScope0 calls, i.e., excessive handshakes.
Modification:
Reimplement MsgHdrMemoryArray to allocate one large segment and slice for each MsgHdrMemory.
collapses 4096 shared closes into a single close.
Result:
Fixes #16174