JVM 堆参数

野性酷女 2023-02-11 03:19 3阅读 0赞

**堆相关参数：**  
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/**
     *  演示内存的分配策略
     */
    public class Demo2_1 {
        private static final int _512KB = 512 * 1024;
        private static final int _1MB = 1024 * 1024;
        private static final int _6MB = 6 * 1024 * 1024;
        private static final int _7MB = 7 * 1024 * 1024;
        private static final int _8MB = 8 * 1024 * 1024;
    
        // -Xms20M -Xmx20M -Xmn10M -XX:+UseSerialGC -XX:+PrintGCDetails -verbose:gc -XX:-ScavengeBeforeFullGC
        public static void main(String[] args) throws InterruptedException {
        }
    }
    
    Heap
     def new generation   total 9216K, used 984K [0x00000000fec00000, 0x00000000ff600000, 0x00000000ff600000)
      eden space 8192K,  12% used [0x00000000fec00000, 0x00000000fecf6060, 0x00000000ff400000)
      from space 1024K,   0% used [0x00000000ff400000, 0x00000000ff400000, 0x00000000ff500000)
      to   space 1024K,   0% used [0x00000000ff500000, 0x00000000ff500000, 0x00000000ff600000)
     tenured generation   total 10240K, used 0K [0x00000000ff600000, 0x0000000100000000, 0x0000000100000000)
       the space 10240K,   0% used [0x00000000ff600000, 0x00000000ff600000, 0x00000000ff600200, 0x0000000100000000)
     Metaspace       used 2588K, capacity 4486K, committed 4864K, reserved 1056768K
      class space    used 286K, capacity 386K, committed 512K, reserved 1048576K
    
      total 9216K：为什么不是10M，因为to区域没有算，to区域实际不用使用的，只是临时交换时

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![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mjg2ODYzOA_size_16_color_FFFFFF_t_70 4]

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