Lock Reservation

This is blog 7 in the OpenJ9 locking/synchronization series (blog 1). It covers an optimization related to the object-monitors (blog 2), which are used to enforce synchronization for the Java objects. Before reading this blog, one needs to have knowledge about the object-monitors. Please read the blog on the object-monitors before reading this blog. In…

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Class-Specific Spin Parameters (CSSP)

This is blog 8 in the OpenJ9 locking/synchronization series (blog 1). This blog covers an OpenJ9 feature which allows spin control parameters to be varied on a per-class basis. Before reading this blog, one needs to know about the system-monitors (blog 2), object-monitors (blog 3), three-tier spinning (blog 4) and adaptive spinning (blog 5). Please…

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Three-Tier Spinning

This is blog 4 in the OpenJ9 locking/synchronization series (blog 1). Before reading this blog, one needs to know about the system-monitors (blog 2), GC-spinlocks (blog 2), and object-monitors (blog 3). Please read the aforementioned blogs before reading this blog. Three-tier spinning is used to make acquiring locks more efficient when the lock contention is…

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