Pauseless Java: Inside Azul's C4, Falcon and ReadyNow

An airhacks.fm conversation with Simon Ritter about:

Azul Zulu as a straight build of openJDK versus Azul Zing/Prime as the commercial high-performance JVM,

improving Java performance without changing application code,

C4 the Continuously Concurrent Compacting Collector,

fully concurrent and compacting pauseless garbage collection,

reaching a global safe point and millisecond-level pauses,

a loaded-value read barrier intercepting every object read with a two-instruction test-and-jump,

using bits in the object header limiting heaps to 20 terabytes,

the one and a half day garbage collection pause anecdote on a terabyte-scale heap,

latency-sensitive workloads like high-frequency trading and ad brokering,

ZGC as a garbage collector heavily based on the published C4 work,

Falcon a JIT compiler based on LLVM replacing HotSpot's C2,