https://abiasforaction.net/understanding-jvm-garbage-collection-part-1/
JVM overview
GC approaches
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ref counting
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tracing garbage collection
https://abiasforaction.net/understanding-jvm-garbage-collection-part-2/ -
Mark phase
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Sweep phase
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Compaction phase
To run the garbage collection safely (without any concurrency issues) older GC algorithms stop all application threads (Stop the World Pauses) so that memory can be safely reclaimed. Thus a GC cycle does the following:
- Stops all application threads
- Runs garbage collection
- Starts all application threads again
Variations
- Mark Sweep
- Mark Sweep and Compaction
- Mark and Copy
