Handshaking in HotSpot JVM: Improving Thread Safety and Performance

Explore the intricacies of HotSpot JVM's thread management in this 44-minute conference talk from Jfokus VM Tech Summit 2020. Dive deep into the implementation of the new thread local poll mechanism, which replaces global safepoints for accessing thread local resources safely. Learn how this innovation targets individual threads, removes inter-thread dependencies, and allows for direct execution of per-thread operations when the target thread is in a safe state. Discover the benefits of this approach in reducing application latency and improving throughput. Examine current uses of handshaking in ZGC, deoptimization, and lock revocation, and get a glimpse of potential future applications. Gain insights from Oracle HotSpot runtime team member Robbin Ehn as he shares his expertise in concurrency, locking, and safepointing.