#Serial images serial
#Serial images full

If no maximum Java heap size is specified, a native image that uses the Serial GC will set its maximum Java heap size to 80% of the physical memory size.ДЇor example, on a machine with 4GB of RAM, the maximum Java heap size will be set to 3.2GB.

#Serial images full

Typically, a young collection is much faster than an full collection, however doing full collections is important for keeping the memory footprint low.Д«y default, the GC tries to balance the time that is spent in young and full collections. When the old generation becomes full, a full collection is triggered. Objects that are alive in the young generation, will be moved to the old generation, thus freeing up the young generation for subsequent object allocations. The young generation is reserved for the allocation of new objects and when this part becomes full, a young collection is triggered. Those chunks are the GC-internal unit for memory allocation and memory reclamation. It divides the Java heap into a young and an old generation.Д®ach generation consists of a set of equally sized chunks, each a contiguous range of virtual memory. In its core, the Serial GC is a simple (non-parallel, non-concurrent) stop and copy GC.

# Build a native image that uses the serial GC with default settings It is also possible to explicitly enable the Serial GC by passing the option -gc=serial to the native image builder. If no other GC is specified, the Serial GC will be used implicitly as the default on both GraalVM Community and Enterprise Edition. The Serial GC is optimized for low footprint and small Java heap sizes. The young generation size determines the amount of Java memory that can be allocated without triggering a garbage collection.The minimum Java heap size defines how much memory the GC may always assume as reserved for the Java heap, no matter how little of that memory is actually used.Note: The maximum heap size is only the upper limit for the Java heap and not necessarily the upper limit for the total amount of consumed memory, as Native Image places some data such as thread stacks, just-in-time compiled code, and internal data structures in memory that is separate from the Java heap. If the Java heap is full and the GC is unable reclaim sufficient memory for a Java object allocation, the allocation will fail with the OutOfMemoryError. The maximum Java heap size defines the upper limit for the size of the whole Java heap.The exact values may depend on the system configuration and the used GC. Young generation pauses can be minimized by using a small young generation at the expense of throughput.Д«y default, Native Image automatically determines values for the Java heap settings that are listed below. Footprint is the working set of a process, measured in pages and cache lines.Д¬hoosing settings for the Java heap is always a trade-off between these metrics.ДЇor example, a very large young generation may maximize throughput, but does so at the expense of footprint and latency.Garbage collection pauses negatively affect the responsiveness.

Latency is the responsiveness of an application.

Throughput is the percentage of total time not spent in garbage collection considered over long periods of time.

The primary metrics for garbage collection are throughput, latency, and footprint: To enable the Epsilon GC, specify the option -gc=epsilon at image build time. The primary use case for this GC are very short running applications that only allocate a small amount of memory.

The Epsilon GC (available with GraalVM 21.2 or later) is a no-op garbage collector that does not do any garbage collection and therefore never frees any allocated memory.

To enable G1, specify the option -gc=G1 at image build time.Д¬urrently, G1 can only be used in native images that are built on Linux for AMD64. The G1 GC (only available with GraalVM Enterprise Edition) is a multi-threaded GC that is optimized to reduce stop-the-world pauses and therefore improve latency, while achieving high throughput.It is optimized for low memory footprint and small Java heap sizes. The Serial GC is the default GC in both GraalVM Community and Enterprise Edition.When the heap becomes full, a garbage collection is triggered to reclaim memory of objects that are no longer used.ДЇor managing the Java heap, Native Image provides different garbage collector (GC) implementations: The Java heap is created when the native image starts up, and may increase or decrease in size while the native image runs. Java objects that a native image allocates at run time reside in the area called вЂњthe Java heapвЂќ. That runtime includes all necessary components, and one of them is the memory management. A native image, when being executed, does not run on the Java HotSpot VM but on the runtime system provided with GraalVM.