Reducing Write Barrier Overheads for Orthogonal Persistence
summary
Implements replication-based persistency (RBP) inside HotSpot VM (OpenJDK) and shifts the expensive fence from every putfield to copier-weight handshakes that synchronize the copier with other threads, reducing the writer-side overhead by about 75% (from a 43.7% penalty close to baseline) and giving a 23% speedup over RBP when no durable roots exist. A persistence-aware escape analysis statically elides many handshakes (eliminating ~52% of the overheads); worst-case handshake cost was ~37.9%, and final copier-weight overheads drop to ~2.4% on evaluated DaCapo and persistent-data-structure benchmarks.
AI-written summary · about
chapters (16)
- 0:00Orthogonal persistence intro
- 1:17Hybrid NVM systems
- 2:42Replication persistence model
- 3:45NVM concurrent access issues
- 6:36Weak memory reordering
- 8:03Writer barrier overheads
- 10:14Shift overhead to copier
- 13:52Copier weight gains
- 14:55Frequent persistent copying
- 17:06Persistent escape analysis
- 21:00Static analysis handshakes
- 22:46Related work challenges
- 23:07Conclusion and future
- 24:10Q&A: Crash consistency
- 25:12Q&A: Multiple copiers
- 26:38Q&A: Unexplored overheads
related talks
17mHow JDK 26 Improves G1's Throughput
54mJava performance techniques The cost of HotSpot runtime optimizations
53mJava Performance Update 2024
56mProject Lilliput: Shrinking Object Headers in the HotSpot JVM
01h 12mHidden pearls for high-performance-persistence in Java
55mThe Performance Engineer's Guide To Java HotSpot
39mMemory Efficient Java
44mJava at Speed: Building a Better JVM.