新生代大小对GC的影响

import java.util.Vector;

/**
 * Created by xxd on 2017/4/2.
 */
public class DumpOOM {
    public static void main(String[] args){
        Vector v = new Vector();
        for (int i=0;i<25;i++){
            v.add(new byte[1*1024*1024]);
        }
    }
}

"C:Program FilesJavajdk1.8.0_121injava" -Xmx20m -Xms20m -Xmn1m -XX:SurvivorRatio=2 -XX:+PrintGCDetails -Didea.launcher.port=7534 "-Didea.launcher.bin.path=E:Program Files (x86)JetBrainsIntelliJ IDEA Community Edition 2016.3in" -Dfile.encoding=UTF-8 -classpath "C:Program FilesJavajdk1.8.0_121jrelibcharsets.jar;C:Program FilesJavajdk1.8.0_121jrelibdeploy.jar;C:Program FilesJavajdk1.8.0_121jrelibextaccess-bridge-64.jar;C:Program FilesJavajdk1.8.0_121jrelibextcldrdata.jar;C:Program FilesJavajdk1.8.0_121jrelibextdnsns.jar;C:Program FilesJavajdk1.8.0_121jrelibextjaccess.jar;C:Program FilesJavajdk1.8.0_121jrelibextjfxrt.jar;C:Program FilesJavajdk1.8.0_121jrelibextlocaledata.jar;C:Program FilesJavajdk1.8.0_121jrelibext
ashorn.jar;C:Program FilesJavajdk1.8.0_121jrelibextsunec.jar;C:Program FilesJavajdk1.8.0_121jrelibextsunjce_provider.jar;C:Program FilesJavajdk1.8.0_121jrelibextsunmscapi.jar;C:Program FilesJavajdk1.8.0_121jrelibextsunpkcs11.jar;C:Program FilesJavajdk1.8.0_121jrelibextzipfs.jar;C:Program FilesJavajdk1.8.0_121jrelibjavaws.jar;C:Program FilesJavajdk1.8.0_121jrelibjce.jar;C:Program FilesJavajdk1.8.0_121jrelibjfr.jar;C:Program FilesJavajdk1.8.0_121jrelibjfxswt.jar;C:Program FilesJavajdk1.8.0_121jrelibjsse.jar;C:Program FilesJavajdk1.8.0_121jrelibmanagement-agent.jar;C:Program FilesJavajdk1.8.0_121jrelibplugin.jar;C:Program FilesJavajdk1.8.0_121jrelib
esources.jar;C:Program FilesJavajdk1.8.0_121jrelib
t.jar;F:idea_workspacejvmDebugoutproductionjvmDebug;E:Program Files (x86)JetBrainsIntelliJ IDEA Community Edition 2016.3libidea_rt.jar" com.intellij.rt.execution.application.AppMain NewSizeDemo

[GC (Allocation Failure) [PSYoungGen: 512K->504K(1024K)] 512K->512K(19968K), 0.0007921 secs] [Times: user=0.00 sys=0.00, real=0.00 secs] 

[GC (Allocation Failure) [PSYoungGen: 1016K->488K(1024K)] 1024K->684K(19968K), 0.0006238 secs] [Times: user=0.00 sys=0.00, real=0.00 secs] 

Java HotSpot(TM) 64-Bit Server VM warning: NewSize (1536k) is greater than the MaxNewSize (1024k). A new max generation size of 1536k will be used. 

Heap

 PSYoungGen      total 1024K, used 582K [0x00000000ffe80000, 0x0000000100000000, 0x0000000100000000)

  eden space 512K, 18% used [0x00000000ffe80000,0x00000000ffe97bd0,0x00000000fff00000)

  from space 512K, 95% used [0x00000000fff80000,0x00000000ffffa020,0x0000000100000000)

  to   space 512K, 0% used [0x00000000fff00000,0x00000000fff00000,0x00000000fff80000)

 ParOldGen       total 18944K, used 10436K [0x00000000fec00000, 0x00000000ffe80000, 0x00000000ffe80000)

  object space 18944K, 55% used [0x00000000fec00000,0x00000000ff6310b0,0x00000000ffe80000)

 Metaspace       used 3305K, capacity 4494K, committed 4864K, reserved 1056768K

  class space    used 362K, capacity 386K, committed 512K, reserved 1048576K

Process finished with exit code 0

===================================================================================================================================================

-Xmx20m -Xms20m -Xmn7m -XX:SurvivorRatio=2 -XX:+PrintGCDetails

"C:Program FilesJavajdk1.8.0_121injava" -Xmx20m -Xms20m -Xmn7m -XX:SurvivorRatio=2 -XX:+PrintGCDetails -Didea.launcher.port=7535 "-Didea.launcher.bin.path=E:Program Files (x86)JetBrainsIntelliJ IDEA Community Edition 2016.3in" -Dfile.encoding=UTF-8 -classpath "C:Program FilesJavajdk1.8.0_121jrelibcharsets.jar;C:Program FilesJavajdk1.8.0_121jrelibdeploy.jar;C:Program FilesJavajdk1.8.0_121jrelibextaccess-bridge-64.jar;C:Program FilesJavajdk1.8.0_121jrelibextcldrdata.jar;C:Program FilesJavajdk1.8.0_121jrelibextdnsns.jar;C:Program FilesJavajdk1.8.0_121jrelibextjaccess.jar;C:Program FilesJavajdk1.8.0_121jrelibextjfxrt.jar;C:Program FilesJavajdk1.8.0_121jrelibextlocaledata.jar;C:Program FilesJavajdk1.8.0_121jrelibext ashorn.jar;C:Program FilesJavajdk1.8.0_121jrelibextsunec.jar;C:Program FilesJavajdk1.8.0_121jrelibextsunjce_provider.jar;C:Program FilesJavajdk1.8.0_121jrelibextsunmscapi.jar;C:Program FilesJavajdk1.8.0_121jrelibextsunpkcs11.jar;C:Program FilesJavajdk1.8.0_121jrelibextzipfs.jar;C:Program FilesJavajdk1.8.0_121jrelibjavaws.jar;C:Program FilesJavajdk1.8.0_121jrelibjce.jar;C:Program FilesJavajdk1.8.0_121jrelibjfr.jar;C:Program FilesJavajdk1.8.0_121jrelibjfxswt.jar;C:Program FilesJavajdk1.8.0_121jrelibjsse.jar;C:Program FilesJavajdk1.8.0_121jrelibmanagement-agent.jar;C:Program FilesJavajdk1.8.0_121jrelibplugin.jar;C:Program FilesJavajdk1.8.0_121jrelib esources.jar;C:Program FilesJavajdk1.8.0_121jrelib t.jar;F:idea_workspacejvmDebugoutproductionjvmDebug;E:Program Files (x86)JetBrainsIntelliJ IDEA Community Edition 2016.3libidea_rt.jar" com.intellij.rt.execution.application.AppMain NewSizeDemo

[GC (Allocation Failure) [PSYoungGen: 3343K->864K(5632K)] 3343K->1896K(18944K), 0.0025715 secs] [Times: user=0.00 sys=0.00, real=0.00 secs] 

[GC (Allocation Failure) [PSYoungGen: 4056K->1520K(5632K)] 5088K->2820K(18944K), 0.0010995 secs] [Times: user=0.00 sys=0.00, real=0.00 secs] 

[GC (Allocation Failure) [PSYoungGen: 4688K->1528K(5632K)] 5988K->2828K(18944K), 0.0006183 secs] [Times: user=0.00 sys=0.00, real=0.00 secs] 

Heap

 PSYoungGen      total 5632K, used 3707K [0x00000000ff900000, 0x0000000100000000, 0x0000000100000000)

  eden space 4096K, 53% used [0x00000000ff900000,0x00000000ffb20fa8,0x00000000ffd00000)

  from space 1536K, 99% used [0x00000000ffd00000,0x00000000ffe7e040,0x00000000ffe80000)

  to   space 1536K, 0% used [0x00000000ffe80000,0x00000000ffe80000,0x0000000100000000)

 ParOldGen       total 13312K, used 1300K [0x00000000fec00000, 0x00000000ff900000, 0x00000000ff900000)

  object space 13312K, 9% used [0x00000000fec00000,0x00000000fed45020,0x00000000ff900000)

 Metaspace       used 3269K, capacity 4494K, committed 4864K, reserved 1056768K

  class space    used 360K, capacity 386K, committed 512K, reserved 1048576K

Process finished with exit code 0

===================================================================================================================================================

-Xmx20m -Xms20m -Xmn15m -XX:SurvivorRatio=2 -XX:+PrintGCDetails

"C:Program FilesJavajdk1.8.0_121injava" -Xmx20m -Xms20m -Xmn15m -XX:SurvivorRatio=2 -XX:+PrintGCDetails -Didea.launcher.port=7536 "-Didea.launcher.bin.path=E:Program Files (x86)JetBrainsIntelliJ IDEA Community Edition 2016.3in" -Dfile.encoding=UTF-8 -classpath "C:Program FilesJavajdk1.8.0_121jrelibcharsets.jar;C:Program FilesJavajdk1.8.0_121jrelibdeploy.jar;C:Program FilesJavajdk1.8.0_121jrelibextaccess-bridge-64.jar;C:Program FilesJavajdk1.8.0_121jrelibextcldrdata.jar;C:Program FilesJavajdk1.8.0_121jrelibextdnsns.jar;C:Program FilesJavajdk1.8.0_121jrelibextjaccess.jar;C:Program FilesJavajdk1.8.0_121jrelibextjfxrt.jar;C:Program FilesJavajdk1.8.0_121jrelibextlocaledata.jar;C:Program FilesJavajdk1.8.0_121jrelibext ashorn.jar;C:Program FilesJavajdk1.8.0_121jrelibextsunec.jar;C:Program FilesJavajdk1.8.0_121jrelibextsunjce_provider.jar;C:Program FilesJavajdk1.8.0_121jrelibextsunmscapi.jar;C:Program FilesJavajdk1.8.0_121jrelibextsunpkcs11.jar;C:Program FilesJavajdk1.8.0_121jrelibextzipfs.jar;C:Program FilesJavajdk1.8.0_121jrelibjavaws.jar;C:Program FilesJavajdk1.8.0_121jrelibjce.jar;C:Program FilesJavajdk1.8.0_121jrelibjfr.jar;C:Program FilesJavajdk1.8.0_121jrelibjfxswt.jar;C:Program FilesJavajdk1.8.0_121jrelibjsse.jar;C:Program FilesJavajdk1.8.0_121jrelibmanagement-agent.jar;C:Program FilesJavajdk1.8.0_121jrelibplugin.jar;C:Program FilesJavajdk1.8.0_121jrelib esources.jar;C:Program FilesJavajdk1.8.0_121jrelib t.jar;F:idea_workspacejvmDebugoutproductionjvmDebug;E:Program Files (x86)JetBrainsIntelliJ IDEA Community Edition 2016.3libidea_rt.jar" com.intellij.rt.execution.application.AppMain NewSizeDemo

[GC (Allocation Failure) [PSYoungGen: 7627K->1920K(11776K)] 7627K->1928K(16896K), 0.0014507 secs] [Times: user=0.00 sys=0.00, real=0.00 secs] 

Heap

 PSYoungGen      total 11776K, used 6338K [0x00000000ff100000, 0x0000000100000000, 0x0000000100000000)

  eden space 8192K, 53% used [0x00000000ff100000,0x00000000ff550b58,0x00000000ff900000)

  from space 3584K, 53% used [0x00000000ff900000,0x00000000ffae0040,0x00000000ffc80000)

  to   space 3584K, 0% used [0x00000000ffc80000,0x00000000ffc80000,0x0000000100000000)

 ParOldGen       total 5120K, used 8K [0x00000000fec00000, 0x00000000ff100000, 0x00000000ff100000)

  object space 5120K, 0% used [0x00000000fec00000,0x00000000fec02000,0x00000000ff100000)

 Metaspace       used 3279K, capacity 4494K, committed 4864K, reserved 1056768K

  class space    used 361K, capacity 386K, committed 512K, reserved 1048576K

Process finished with exit code 0

===================================================================================================================================================