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@stingh711
Created July 17, 2012 07:35
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Try to make JVM only do full GC
class OnlyFullGc {
private static final int _1M = 1024 * 1024;
//java -verbose:gc -XX:+PrintGCDetails -XX:PretenureSizeThreshold=3145728 -Xms20M -Xmx20M -Xmn10M OnlyFullGc
//1
//2
//[GC [Tenured: 9216K->4237K(10240K), 0.0110910 secs] 9543K->4237K(19456K), [Perm : 91K->91K(12288K)], 0.0113940 secs] [Times: user=0.01 sys=0.00, real=0.01 secs]
//3
//Heap
//def new generation total 9216K, used 491K [0x8e510000, 0x8ef10000, 0x8ef10000)
//eden space 8192K, 6% used [0x8e510000, 0x8e58af00, 0x8ed10000)
//from space 1024K, 0% used [0x8ed10000, 0x8ed10000, 0x8ee10000)
//to space 1024K, 0% used [0x8ee10000, 0x8ee10000, 0x8ef10000)
//tenured generation total 10240K, used 9357K [0x8ef10000, 0x8f910000, 0x8f910000)
//the space 10240K, 91% used [0x8ef10000, 0x8f833468, 0x8f833600, 0x8f910000)
//compacting perm gen total 12288K, used 91K [0x8f910000, 0x90510000, 0x93910000)
//the space 12288K, 0% used [0x8f910000, 0x8f926eb8, 0x8f927000, 0x90510000)
//ro space 10240K, 60% used [0x93910000, 0x93f1dba0, 0x93f1dc00, 0x94310000)
//rw space 12288K, 61% used [0x94310000, 0x94a72ed0, 0x94a73000, 0x94f10000)
public static void main(String[] args) {
byte[] a0, a1;
a0 = new byte[5 * _1M];
System.out.println(1);
a1 = new byte[4 * _1M];
System.out.println(2);
a0 = null;
a0 = new byte[5 * _1M];
System.out.println(3);
}
}
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second version works

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