拓胜技术专家教你如何深入理解JVM调优

1/16Java(2/161...........................................................................................................................................52JAVA........................................................................................................52.1..........................................................................................................................52.2...........................................................................................................63JAVA........................................................................................................83.1Java...........................................................................................................83.2Java.........................................................................................................104JAVA...........................................................................................144.1GC...........................................................................................................144.2JIT...........................................................................................................154.3Java..................................................................................................155.....................................................................................................................................166.................................................................................................................................163/161JVM....................................................................................................................102JVM....................................................................................................................113JVMGC/Hotspot..................................................................................................134JVM.............................................................................................................144/16JavaJAVAJ2EEJAVAJAVAJAVAJAVAJAVAJAVASUNJVMJavaVirtualMachineJAVAGCGarbageCollectionHotSpotJavaJITJust-In-Time5/161JavaJavaJavaJVMJavaJDKCPUJavaJava2JAVA2.1JavaJavaJavaJavaJavaJavaClassJavaJavaJavaJavaCPUJavaJavaJavaJavaJavaJavaJavaHotspot80/208020JavaJavaClassJavaPCJavaJavaPCCPUIPJavaHotspotVMJavaJavaJavaJavaJava6/161JavaJavanewHeapC/C++C/C++4Gmalloc/C/C++newJavaJavaJavaGCJava-Xms-XmsJavaJavaJavaJavaGC2.2JavaJavaJava7/16JDKC/C++deleteJavaCPU10JavaGCGCJVM——JavaJavaC/C++APIJavaJDKRunableThreadJavaJVMJVMJVMJVMJVMJVMJava”——JavaSynchronizedJavamonitorentermonitorexitSynchronizedSynchronizedmonitorentermonitorexitJVMmonitorentermonitorexit8/162Java3JAVA3.1JavaJavaSolaris1.4.2-d32-d64JavaVM3264326464CPU64-server6464CPU326432-client-serverJVMClientServerHotspotJVMJITJVMClientGUIServer9/16-hotspotHotspotJVMClientHotspot-cp-classpathJVMJava*.zip*.jar*.classJVM-Dname=valueJavaJVMargumentJavasystem.getProperty-DJVMmain-verbose:class-verbose:gc-verbose:jni:class:gc:jniJVM:gcJVM-version-showversion-versionJVM-showversionJVM-esa-enableassertions10/16-da-disableassertions1JVM3.2JavaJavaSolaris1.4.2HotspotVM-XmixedJVMHotspotHotspotJVM-XintJVMJVM-Xbootclasspath-Xnoclassgc-Xincgc-Xloggc:fileGC-Xbatch-XmssizeJVM-XmxsizeJVM-XsssizeJVM-Xprof-Xrunhprofheapcpu-Xdebug11/16-Xfuture-Xrs-Xcheck:jni2JVMJavaHotspotGCSolaris1.4.2–XJVM–XX-Xincgc-Xnoincgc-XX:MaxHeapFreeRatio=MaximumJVM70%GC70GC-X:MinHeapFreeRation=MinimumJVM40%GC40%GC-XintJIT-XX:+UseBoundThreadsSolarisonlyJavaJVMSolaris-XX:+UseParallelGC-XX:+UseAltSigs-XX:+PrintCompilationJIT-XX:+UseV8InstrsOnly-XX:MaxInlineSize=size-XX:FreqInlineSize=size12/16-XX:-AllowUserSignalHandlers-XX:AltStackSize=16384-XX:+MaxFDLimitJVMSolarisonly-XX:-UseLWPSynchronizationLWPJavaJVMSolarisJVM-XX:+UseThreadPriorities-XX:-CITimeHotspot-XX:-PrintTenuringDistribution-XX:+DisableExplicitGCsystem.gc()-XX:TargetSurvivorRatio=50GC-XX:CompileThreshold=10000-server10000-client1500JIT-XX:MaxNewSize=32m-XX:NewRatio=2SUNParc–server21Intel121-XX:NewSize=22282242K13/16-XX:-UseSpinning-XX:PreBlockSpin=10-XX:ReservedCodeCacheSize=32m-XX:SurvivorRatio=64-XX:ThreadStackSize=512K0Sparc:512KSolarisIntel:256KSparc64bit:10240-XX:+UseTLABSUNSparc–servertruefalse-XX:-UseISMISM18K2ISM/etc/systemsetshmsys:shminfo_shmmax=0xffffffffsetshmsys:shminfo_shmseg=323JVMGC/HotspotHotspotGCSolaris1.4.2heap=valueJVMcpu=valueJVMCPUCPUmonitor=valueJVMSocketformat=valueascii14/16file=valuejava.hprof.txtnet=valueSocketdepth=value4cutoff=valuelineno=valuethread=valuedoe=valueJVM4JVMJVMJavaProfileJprobeOptimizeITJprobe4JAVA4.1GCJVMJVM-XX:NewRatio=2//-XX:NewSize=2228224//2K4K8K-XX:MaxNewSize//-XX:MaxPermSize=64m//64M-XX:SurvivorRatio//GC-Xxincgc//-XX:+UseConcMarkSweepGC//-Xverifyheap//DebugGC-XX:TargetSurvivorRatio=50//GC15/16JVM-Xms//-Xmx//-XX:MinFreeHeapRatio=40//GCJVM-XX:MaxHeapFreeRatio70//GCJVM-XX:+AggressiveHeap//JVMJVM1G//-Xms-XmxJVM//U-NICA4.2JITJVMJava-server//Hotspot//-Xmaxjitcodesize32m//-Xint//-Xtime//JIT-XX:+D