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/**
*
* @描述：对象优先在Eden分配
* @author	feiZhou
* @date	2018年11月21日上午8:30:41
* @version 1.0
*/
public class EdenAllocation1 {
private static final int _1MB = 1024*1024;
/**
* VM参数：-XX:+UseSerialGC -XX:+PrintGCDetails -verbose:gc -Xms20M -Xmx20M -Xmn10M -XX:SurvivorRatio=8
*/
@SuppressWarnings("unused")
public static void main(String[] args) {
byte[] allocation1,allocation2,allocation3,allocation4;
allocation1 = new byte[2 * _1MB];
allocation2 = new byte[2 * _1MB];
allocation3 = new byte[2 * _1MB];
allocation4 = new byte[4 * _1MB];
}
}

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[GC (Allocation Failure) [DefNew: 7808K->603K(9216K), 0.0062181 secs] 7808K->6747K(19456K), 0.0074891 secs] [Times: user=0.00 sys=0.00, real=0.01 secs]
Heap
def new generation
total 9216K, used 4781K [0x00000000fec00000, 0x00000000ff600000, 0x00000000ff600000)
eden space 8192K,
51% used [0x00000000fec00000, 0x00000000ff014930, 0x00000000ff400000)
from space 1024K,
58% used [0x00000000ff500000, 0x00000000ff596d10, 0x00000000ff600000)
to
space 1024K,
0% used [0x00000000ff400000, 0x00000000ff400000, 0x00000000ff500000)
tenured generation
total 10240K, used 6144K [0x00000000ff600000, 0x0000000100000000, 0x0000000100000000)
the space 10240K,
60% used [0x00000000ff600000, 0x00000000ffc00030, 0x00000000ffc00200, 0x0000000100000000)
Metaspace
used 3199K, capacity 4496K, committed 4864K, reserved 1056768K
class space
used 346K, capacity 388K, committed 512K, reserved 1048576K

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[GC (Allocation Failure) [DefNew: 7808K->603K(9216K), 0.0062181 secs] 7808K->6747K(19456K), 0.0074891 secs] [Times: user=0.00 sys=0.00, real=0.01 secs]
Heap