Pauseless Java Garbage Collection

Azul’s Continuously Concurrent Compacting Garbage Collector (C4) is the only generational pauseless garbage collector available in Java.

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The C4 collector allows JVMs to smoothly scale up to a heap size of 20 terabytes, and sustain multi-gigabyte-per-sec allocation rates, while maintaining measurable jitter and response time.

Maintain consistent response times for mission critical enterprise applications

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Supported by the strong invariants of the Load Value Barrier (LVB), C4 operates as a fully concurrent collector across three continuous activities: marking to discover live objects, relocation/compaction to reclaim space, and remapping/reference processing to repair pointers as objects move.

Because every heap reference is verified on load, any pointer to a relocated object is corrected on the fly, preserving correctness under heavy mutation without stop-the-world fallback. The C4 algorithm also drives a dynamic page lifecycle—continuously mapping pages for allocation, protecting them to intercept stale loads, remapping addresses during relocation, and unmapping freed pages—enabling “hand-over-hand” compaction and rapid reuse of memory.

Understanding Java Garbage Collection

Garbage Collection (GC) is an integral part of application behavior on Java platforms, and developers need to understand how tuning garbage collector mechanisms can affect runtime performance, scalability, and reliability.

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Accommodate your requirements for performance, security and value

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