文章目錄
1.標準參數
1.1.概述
1.標準參數：我們認爲隨着jdk版本的升級，這些參數是不會變化的；
1.2.-x參數
1.2.1. java -version
localhost:~ gaoxinfu$ java -version
java version "1.8.0_211"
Java(TM) SE Runtime Environment (build 1.8.0_211-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.211-b12, mixed mode)
localhost:~ gaoxinfu$
說明
1.java虛擬機的模式是mixed模式(混合模式):既可以解釋執行，又可以編譯執行;
（Java採用的是解釋和編譯混合的模式。它首先通過javac將源碼編譯成字節碼文件class.然後在運行的時候通過解釋器或者JIT將字節碼轉換成最終的機器碼。）
設置爲解釋執行模式
localhost:~ gaoxinfu$ java -Xint -version
java version "1.8.0_211"
Java(TM) SE Runtime Environment (build 1.8.0_211-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.211-b12, interpreted mode)
設置爲編譯執行模式
localhost:~ gaoxinfu$ java -Xcompiled -version
java version "1.8.0_211"
Java(TM) SE Runtime Environment (build 1.8.0_211-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.211-b12, compiled mode)
設置爲混合模式
localhost:~ gaoxinfu$ java -Xmixed -version
java version "1.8.0_211"
Java(TM) SE Runtime Environment (build 1.8.0_211-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.211-b12, mixed mode)
localhost:~ gaoxinfu$
1.2.1.java -help 獲取java參數幫助命令
localhost:~ gaoxinfu$ java -help
用法: java [-options] class [args...]
(執行類)
或 java [-options] -jar jarfile [args...]
(執行 jar 文件)
其中選項包括:
-d32 使用 32 位數據模型 (如果可用)
-d64 使用 64 位數據模型 (如果可用)
-server 選擇 "server" VM
默認 VM 是 server,
因爲您是在服務器類計算機上運行。
-cp <目錄和 zip/jar 文件的類搜索路徑>
-classpath <目錄和 zip/jar 文件的類搜索路徑>
用 : 分隔的目錄, JAR 檔案
和 ZIP 檔案列表, 用於搜索類文件。
-D<名稱>=<值>
設置系統屬性
-verbose:[class|gc|jni]
啓用詳細輸出
-version 輸出產品版本並退出
-version:<值>
警告: 此功能已過時, 將在
未來發行版中刪除。
需要指定的版本才能運行
-showversion 輸出產品版本並繼續
-jre-restrict-search | -no-jre-restrict-search
警告: 此功能已過時, 將在
未來發行版中刪除。
在版本搜索中包括/排除用戶專用 JRE
-? -help 輸出此幫助消息
-X 輸出非標準選項的幫助
-ea[:<packagename>...|:<classname>]
-enableassertions[:<packagename>...|:<classname>]
按指定的粒度啓用斷言
-da[:<packagename>...|:<classname>]
-disableassertions[:<packagename>...|:<classname>]
禁用具有指定粒度的斷言
-esa | -enablesystemassertions
啓用系統斷言
-dsa | -disablesystemassertions
禁用系統斷言
-agentlib:<libname>[=<選項>]
加載本機代理庫 <libname>, 例如 -agentlib:hprof
另請參閱 -agentlib:jdwp=help 和 -agentlib:hprof=help
-agentpath:<pathname>[=<選項>]
按完整路徑名加載本機代理庫
-javaagent:<jarpath>[=<選項>]
加載 Java 編程語言代理, 請參閱 java.lang.instrument
-splash:<imagepath>
使用指定的圖像顯示啓動屏幕
有關詳細信息, 請參閱 http://www.oracle.com/technetwork/java/javase/documentation/index.html。
localhost:~ gaoxinfu$
2.非標準參數
1.非標準參數，我們認爲隨着jdk版本的升級，這些參數有可能變化的
2.1.-xx參數
2.1.1.Boolean類型：是否使用啓動參數
格式
--XX:[+/-]name #啓用或者停止使用某參數(name)
樣例
-XX:+UseSerialGC
2.1.2.非Boolean類型
格式
--XX:name=value #name是key，value是屬性值
樣例
-XX:MaxHeapSeiz=100M
2.2.其他參數
-Xms1000K等價於-XX:InitialHeapSize=1000K
-Xmx1000M等價於-XX:MaxHeapSize=1000M
-Xss100等K價於-XX:ThreadStackSize=100K
2.2.1.比如：設置棧深度 -Xss100K等價於-XX:ThreadStackSize=100K
運行,發下棧的深度設置的太小了，單個線程不夠，我們用另外一種方式設置200K
成功運行
2.2.2.比如啓動的時候打印出所有的參數信息：-XX:+PrintFlagsFinal
/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/bin/java -agentlib:jdwp=transport=dt_socket,address=127.0.0.1:62333,suspend=y,server=n -XX:+PrintFlagsFinal -javaagent:/Users/gaoxinfu/Library/Caches/IntelliJIdea2019.1/captureAgent/debugger-agent.jar -Dfile.encoding=UTF-8 -classpath "/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/charsets.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/deploy.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/cldrdata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/dnsns.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/jaccess.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/jfxrt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/localedata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/nashorn.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/sunec.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/sunjce_provider.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/sunpkcs11.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/zipfs.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/javaws.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/jce.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/jfr.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/jfxswt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/jsse.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/management-agent.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/plugin.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/resources.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/rt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/lib/ant-javafx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/lib/dt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/lib/javafx-mx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/lib/jconsole.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/lib/packager.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/lib/sa-jdi.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/lib/tools.jar:/Users/gaoxinfu/demo-idea/demo-jdk/demo-jvm/target/classes:/Users/gaoxinfu/.m2/repository/org/springframework/boot/spring-boot-starter-web/2.1.6.RELEASE/spring-boot-starter-web-2.1.6.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/boot/spring-boot-starter/2.1.6.RELEASE/spring-boot-starter-2.1.6.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/boot/spring-boot/2.1.6.RELEASE/spring-boot-2.1.6.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/boot/spring-boot-autoconfigure/2.1.6.RELEASE/spring-boot-autoconfigure-2.1.6.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/boot/spring-boot-starter-logging/2.1.6.RELEASE/spring-boot-starter-logging-2.1.6.RELEASE.jar:/Users/gaoxinfu/.m2/repository/ch/qos/logback/logback-classic/1.2.3/logback-classic-1.2.3.jar:/Users/gaoxinfu/.m2/repository/ch/qos/logback/logback-core/1.2.3/logback-core-1.2.3.jar:/Users/gaoxinfu/.m2/repository/org/apache/logging/log4j/log4j-to-slf4j/2.11.2/log4j-to-slf4j-2.11.2.jar:/Users/gaoxinfu/.m2/repository/org/apache/logging/log4j/log4j-api/2.11.2/log4j-api-2.11.2.jar:/Users/gaoxinfu/.m2/repository/org/slf4j/jul-to-slf4j/1.7.26/jul-to-slf4j-1.7.26.jar:/Users/gaoxinfu/.m2/repository/javax/annotation/javax.annotation-api/1.3.2/javax.annotation-api-1.3.2.jar:/Users/gaoxinfu/.m2/repository/org/yaml/snakeyaml/1.23/snakeyaml-1.23.jar:/Users/gaoxinfu/.m2/repository/org/springframework/boot/spring-boot-starter-json/2.1.6.RELEASE/spring-boot-starter-json-2.1.6.RELEASE.jar:/Users/gaoxinfu/.m2/repository/com/fasterxml/jackson/core/jackson-databind/2.9.9/jackson-databind-2.9.9.jar:/Users/gaoxinfu/.m2/repository/com/fasterxml/jackson/core/jackson-annotations/2.9.0/jackson-annotations-2.9.0.jar:/Users/gaoxinfu/.m2/repository/com/fasterxml/jackson/core/jackson-core/2.9.9/jackson-core-2.9.9.jar:/Users/gaoxinfu/.m2/repository/com/fasterxml/jackson/datatype/jackson-datatype-jdk8/2.9.9/jackson-datatype-jdk8-2.9.9.jar:/Users/gaoxinfu/.m2/repository/com/fasterxml/jackson/datatype/jackson-datatype-jsr310/2.9.9/jackson-datatype-jsr310-2.9.9.jar:/Users/gaoxinfu/.m2/repository/com/fasterxml/jackson/module/jackson-module-parameter-names/2.9.9/jackson-module-parameter-names-2.9.9.jar:/Users/gaoxinfu/.m2/repository/org/springframework/boot/spring-boot-starter-tomcat/2.1.6.RELEASE/spring-boot-starter-tomcat-2.1.6.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/apache/tomcat/embed/tomcat-embed-core/9.0.21/tomcat-embed-core-9.0.21.jar:/Users/gaoxinfu/.m2/repository/org/apache/tomcat/embed/tomcat-embed-el/9.0.21/tomcat-embed-el-9.0.21.jar:/Users/gaoxinfu/.m2/repository/org/apache/tomcat/embed/tomcat-embed-websocket/9.0.21/tomcat-embed-websocket-9.0.21.jar:/Users/gaoxinfu/.m2/repository/org/hibernate/validator/hibernate-validator/6.0.17.Final/hibernate-validator-6.0.17.Final.jar:/Users/gaoxinfu/.m2/repository/javax/validation/validation-api/2.0.1.Final/validation-api-2.0.1.Final.jar:/Users/gaoxinfu/.m2/repository/org/jboss/logging/jboss-logging/3.3.2.Final/jboss-logging-3.3.2.Final.jar:/Users/gaoxinfu/.m2/repository/com/fasterxml/classmate/1.4.0/classmate-1.4.0.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-web/5.1.8.RELEASE/spring-web-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-beans/5.1.8.RELEASE/spring-beans-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-webmvc/5.1.8.RELEASE/spring-webmvc-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-aop/5.1.8.RELEASE/spring-aop-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-context/5.1.8.RELEASE/spring-context-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-expression/5.1.8.RELEASE/spring-expression-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/slf4j/slf4j-api/1.7.26/slf4j-api-1.7.26.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-core/5.1.8.RELEASE/spring-core-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-jcl/5.1.8.RELEASE/spring-jcl-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/asm/asm/3.3.1/asm-3.3.1.jar:/Applications/IntelliJ IDEA.app/Contents/lib/idea_rt.jar" com.gaoxinfu.demo.jvm.DemoJvmApplication
[Global flags]
intx ActiveProcessorCount = -1 {product}
uintx AdaptiveSizeDecrementScaleFactor = 4 {product}
uintx AdaptiveSizeMajorGCDecayTimeScale = 10 {product}
uintx AdaptiveSizePausePolicy = 0 {product}
uintx AdaptiveSizePolicyCollectionCostMargin = 50 {product}
。。。。。。。中間參數太多，省略了
intx hashCode = 5 {product}
Connected to the target VM, address: '127.0.0.1:62333', transport: 'socket'
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.1.6.RELEASE)
2020-03-11 16:17:55.717 INFO 20761 --- [ main] c.gaoxinfu.demo.jvm.DemoJvmApplication : Starting DemoJvmApplication on localhost with PID 20761 (/Users/gaoxinfu/demo-idea/demo-jdk/demo-jvm/target/classes started by gaoxinfu in /Users/gaoxinfu/demo-idea/demo-jdk)
2020-03-11 16:17:55.744 INFO 20761 --- [ main] c.gaoxinfu.demo.jvm.DemoJvmApplication : No active profile set, falling back to default profiles: default
2020-03-11 16:17:57.444 INFO 20761 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8080 (http)
2020-03-11 16:17:57.477 INFO 20761 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2020-03-11 16:17:57.478 INFO 20761 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/9.0.21]
2020-03-11 16:17:57.603 INFO 20761 --- [ main] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2020-03-11 16:17:57.604 INFO 20761 --- [ main] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 1735 ms
2020-03-11 16:17:57.984 INFO 20761 --- [ main] o.s.s.concurrent.ThreadPoolTaskExecutor : Initializing ExecutorService 'applicationTaskExecutor'
2020-03-11 16:17:58.523 INFO 20761 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8080 (http) with context path ''
2020-03-11 16:17:58.528 INFO 20761 --- [ main] c.gaoxinfu.demo.jvm.DemoJvmApplication : Started DemoJvmApplication in 3.442 seconds (JVM running for 4.211)
3.參數修改方式
3.1.開發工具修改：idea 或者 eclipse中VM中修改
3.2.執行linux命令的時候指定參數
如下啓動打印全部jvm參數
java -XX:+PrintFlagsFinal -jar demo-jdk.jar
3.3.在容器中設置，比如tomcat的Catalina.sh文件中修改或者新增
3.4.通過命令對正在運行的jvm進行參數修改(無需修改)：通過jinfo命令去設置
4.如何對我們設置過的jvm參數進行驗證
4.1.案例：-XX:+PrintFlagsFinal -Xms100M -Xmx200M
4.1.1設置：-XX:+PrintFlagsFinal -Xms100M -Xmx200M
比如我們設置：-XX:+PrintFlagsFinal -Xms100M -Xmx200M
-XX:+PrintFlagsFinal ：啓動時打印全部的jvm參數
-Xms100M：設置堆內存最小100M
-Xmx200M：設置堆內存最大200M
4.1.2.啓動springboot應用
/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/bin/java -agentlib:jdwp=transport=dt_socket,address=127.0.0.1:64801,suspend=y,server=n -XX:+PrintFlagsFinal -Xms100M -Xmx200M -javaagent:/Users/gaoxinfu/Library/Caches/IntelliJIdea2019.1/captureAgent/debugger-agent.jar -Dfile.encoding=UTF-8 -classpath "/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/charsets.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/deploy.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/cldrdata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/dnsns.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/jaccess.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/jfxrt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/localedata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/nashorn.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/sunec.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/sunjce_provider.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/sunpkcs11.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/ext/zipfs.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/javaws.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/jce.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/jfr.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/jfxswt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/jsse.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/management-agent.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/plugin.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/resources.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/jre/lib/rt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/lib/ant-javafx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/lib/dt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/lib/javafx-mx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/lib/jconsole.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/lib/packager.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/lib/sa-jdi.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_211.jdk/Contents/Home/lib/tools.jar:/Users/gaoxinfu/demo-idea/demo-jdk/demo-jvm/target/classes:/Users/gaoxinfu/.m2/repository/org/springframework/boot/spring-boot-starter-web/2.1.6.RELEASE/spring-boot-starter-web-2.1.6.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/boot/spring-boot-starter/2.1.6.RELEASE/spring-boot-starter-2.1.6.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/boot/spring-boot/2.1.6.RELEASE/spring-boot-2.1.6.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/boot/spring-boot-autoconfigure/2.1.6.RELEASE/spring-boot-autoconfigure-2.1.6.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/boot/spring-boot-starter-logging/2.1.6.RELEASE/spring-boot-starter-logging-2.1.6.RELEASE.jar:/Users/gaoxinfu/.m2/repository/ch/qos/logback/logback-classic/1.2.3/logback-classic-1.2.3.jar:/Users/gaoxinfu/.m2/repository/ch/qos/logback/logback-core/1.2.3/logback-core-1.2.3.jar:/Users/gaoxinfu/.m2/repository/org/apache/logging/log4j/log4j-to-slf4j/2.11.2/log4j-to-slf4j-2.11.2.jar:/Users/gaoxinfu/.m2/repository/org/apache/logging/log4j/log4j-api/2.11.2/log4j-api-2.11.2.jar:/Users/gaoxinfu/.m2/repository/org/slf4j/jul-to-slf4j/1.7.26/jul-to-slf4j-1.7.26.jar:/Users/gaoxinfu/.m2/repository/javax/annotation/javax.annotation-api/1.3.2/javax.annotation-api-1.3.2.jar:/Users/gaoxinfu/.m2/repository/org/yaml/snakeyaml/1.23/snakeyaml-1.23.jar:/Users/gaoxinfu/.m2/repository/org/springframework/boot/spring-boot-starter-json/2.1.6.RELEASE/spring-boot-starter-json-2.1.6.RELEASE.jar:/Users/gaoxinfu/.m2/repository/com/fasterxml/jackson/core/jackson-databind/2.9.9/jackson-databind-2.9.9.jar:/Users/gaoxinfu/.m2/repository/com/fasterxml/jackson/core/jackson-annotations/2.9.0/jackson-annotations-2.9.0.jar:/Users/gaoxinfu/.m2/repository/com/fasterxml/jackson/core/jackson-core/2.9.9/jackson-core-2.9.9.jar:/Users/gaoxinfu/.m2/repository/com/fasterxml/jackson/datatype/jackson-datatype-jdk8/2.9.9/jackson-datatype-jdk8-2.9.9.jar:/Users/gaoxinfu/.m2/repository/com/fasterxml/jackson/datatype/jackson-datatype-jsr310/2.9.9/jackson-datatype-jsr310-2.9.9.jar:/Users/gaoxinfu/.m2/repository/com/fasterxml/jackson/module/jackson-module-parameter-names/2.9.9/jackson-module-parameter-names-2.9.9.jar:/Users/gaoxinfu/.m2/repository/org/springframework/boot/spring-boot-starter-tomcat/2.1.6.RELEASE/spring-boot-starter-tomcat-2.1.6.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/apache/tomcat/embed/tomcat-embed-core/9.0.21/tomcat-embed-core-9.0.21.jar:/Users/gaoxinfu/.m2/repository/org/apache/tomcat/embed/tomcat-embed-el/9.0.21/tomcat-embed-el-9.0.21.jar:/Users/gaoxinfu/.m2/repository/org/apache/tomcat/embed/tomcat-embed-websocket/9.0.21/tomcat-embed-websocket-9.0.21.jar:/Users/gaoxinfu/.m2/repository/org/hibernate/validator/hibernate-validator/6.0.17.Final/hibernate-validator-6.0.17.Final.jar:/Users/gaoxinfu/.m2/repository/javax/validation/validation-api/2.0.1.Final/validation-api-2.0.1.Final.jar:/Users/gaoxinfu/.m2/repository/org/jboss/logging/jboss-logging/3.3.2.Final/jboss-logging-3.3.2.Final.jar:/Users/gaoxinfu/.m2/repository/com/fasterxml/classmate/1.4.0/classmate-1.4.0.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-web/5.1.8.RELEASE/spring-web-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-beans/5.1.8.RELEASE/spring-beans-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-webmvc/5.1.8.RELEASE/spring-webmvc-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-aop/5.1.8.RELEASE/spring-aop-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-context/5.1.8.RELEASE/spring-context-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-expression/5.1.8.RELEASE/spring-expression-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/slf4j/slf4j-api/1.7.26/slf4j-api-1.7.26.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-core/5.1.8.RELEASE/spring-core-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/org/springframework/spring-jcl/5.1.8.RELEASE/spring-jcl-5.1.8.RELEASE.jar:/Users/gaoxinfu/.m2/repository/asm/asm/3.3.1/asm-3.3.1.jar:/Applications/IntelliJ IDEA.app/Contents/lib/idea_rt.jar" com.gaoxinfu.demo.jvm.DemoJvmApplication
[Global flags]
intx ActiveProcessorCount = -1 {product}
uintx AdaptiveSizeDecrementScaleFactor = 4 {product}
uintx AdaptiveSizeMajorGCDecayTimeScale = 10 {product}
uintx AdaptiveSizePausePolicy = 0 {product}
uintx AdaptiveSizePolicyCollectionCostMargin = 50 {product}
uintx AdaptiveSizePolicyInitializingSteps = 20 {product}
uintx AdaptiveSizePolicyOutputInterval = 0 {product}
uintx AdaptiveSizePolicyWeight = 10 {product}
uintx AdaptiveSizeThroughPutPolicy = 0 {product}
uintx AdaptiveTimeWeight = 25 {product}
bool AdjustConcurrency = false {product}
bool AggressiveHeap = false {product}
bool AggressiveOpts = false {product}
intx AliasLevel = 3 {C2 product}
bool AlignVector = false {C2 product}
intx AllocateInstancePrefetchLines = 1 {product}
intx AllocatePrefetchDistance = 192 {product}
intx AllocatePrefetchInstr = 3 {product}
intx AllocatePrefetchLines = 4 {product}
intx AllocatePrefetchStepSize = 64 {product}
intx AllocatePrefetchStyle = 1 {product}
bool AllowJNIEnvProxy = false {product}
bool AllowNonVirtualCalls = false {product}
bool AllowParallelDefineClass = false {product}
bool AllowUserSignalHandlers = false {product}
bool AlwaysActAsServerClassMachine = false {product}
bool AlwaysCompileLoopMethods = false {product}
bool AlwaysLockClassLoader = false {product}
bool AlwaysPreTouch = false {product}
bool AlwaysRestoreFPU = false {product}
bool AlwaysTenure = false {product}
bool AssertOnSuspendWaitFailure = false {product}
bool AssumeMP = false {product}
intx AutoBoxCacheMax = 128 {C2 product}
uintx AutoGCSelectPauseMillis = 5000 {product}
intx BCEATraceLevel = 0 {product}
intx BackEdgeThreshold = 100000 {pd product}
bool BackgroundCompilation = true {pd product}
uintx BaseFootPrintEstimate = 268435456 {product}
intx BiasedLockingBulkRebiasThreshold = 20 {product}
intx BiasedLockingBulkRevokeThreshold = 40 {product}
intx BiasedLockingDecayTime = 25000 {product}
intx BiasedLockingStartupDelay = 4000 {product}
bool BindGCTaskThreadsToCPUs = false {product}
bool BlockLayoutByFrequency = true {C2 product}
intx BlockLayoutMinDiamondPercentage = 20 {C2 product}
bool BlockLayoutRotateLoops = true {C2 product}
bool BranchOnRegister = false {C2 product}
bool BytecodeVerificationLocal = false {product}
bool BytecodeVerificationRemote = true {product}
bool C1OptimizeVirtualCallProfiling = true {C1 product}
bool C1ProfileBranches = true {C1 product}
bool C1ProfileCalls = true {C1 product}
bool C1ProfileCheckcasts = true {C1 product}
bool C1ProfileInlinedCalls = true {C1 product}
bool C1ProfileVirtualCalls = true {C1 product}
bool C1UpdateMethodData = true {C1 product}
intx CICompilerCount := 3 {product}
bool CICompilerCountPerCPU = true {product}
bool CITime = false {product}
bool CMSAbortSemantics = false {product}
uintx CMSAbortablePrecleanMinWorkPerIteration = 100 {product}
intx CMSAbortablePrecleanWaitMillis = 100 {manageable}
uintx CMSBitMapYieldQuantum = 10485760 {product}
uintx CMSBootstrapOccupancy = 50 {product}
bool CMSClassUnloadingEnabled = true {product}
uintx CMSClassUnloadingMaxInterval = 0 {product}
bool CMSCleanOnEnter = true {product}
bool CMSCompactWhenClearAllSoftRefs = true {product}
uintx CMSConcMarkMultiple = 32 {product}
bool CMSConcurrentMTEnabled = true {product}
uintx CMSCoordinatorYieldSleepCount = 10 {product}
bool CMSDumpAtPromotionFailure = false {product}
bool CMSEdenChunksRecordAlways = true {product}
uintx CMSExpAvgFactor = 50 {product}
bool CMSExtrapolateSweep = false {product}
uintx CMSFullGCsBeforeCompaction = 0 {product}
uintx CMSIncrementalDutyCycle = 10 {product}
uintx CMSIncrementalDutyCycleMin = 0 {product}
bool CMSIncrementalMode = false {product}
uintx CMSIncrementalOffset = 0 {product}
bool CMSIncrementalPacing = true {product}
uintx CMSIncrementalSafetyFactor = 10 {product}
uintx CMSIndexedFreeListReplenish = 4 {product}
intx CMSInitiatingOccupancyFraction = -1 {product}
uintx CMSIsTooFullPercentage = 98 {product}
double CMSLargeCoalSurplusPercent = 0.950000 {product}
double CMSLargeSplitSurplusPercent = 1.000000 {product}
bool CMSLoopWarn = false {product}
uintx CMSMaxAbortablePrecleanLoops = 0 {product}
intx CMSMaxAbortablePrecleanTime = 5000 {product}
uintx CMSOldPLABMax = 1024 {product}
uintx CMSOldPLABMin = 16 {product}
uintx CMSOldPLABNumRefills = 4 {product}
uintx CMSOldPLABReactivityFactor = 2 {product}
bool CMSOldPLABResizeQuicker = false {product}
uintx CMSOldPLABToleranceFactor = 4 {product}
bool CMSPLABRecordAlways = true {product}
uintx CMSParPromoteBlocksToClaim = 16 {product}
bool CMSParallelInitialMarkEnabled = true {product}
bool CMSParallelRemarkEnabled = true {product}
bool CMSParallelSurvivorRemarkEnabled = true {product}
uintx CMSPrecleanDenominator = 3 {product}
uintx CMSPrecleanIter = 3 {product}
uintx CMSPrecleanNumerator = 2 {product}
bool CMSPrecleanRefLists1 = true {product}
bool CMSPrecleanRefLists2 = false {product}
bool CMSPrecleanSurvivors1 = false {product}
bool CMSPrecleanSurvivors2 = true {product}
uintx CMSPrecleanThreshold = 1000 {product}
bool CMSPrecleaningEnabled = true {product}
bool CMSPrintChunksInDump = false {product}
bool CMSPrintEdenSurvivorChunks = false {product}
bool CMSPrintObjectsInDump = false {product}
uintx CMSRemarkVerifyVariant = 1 {product}
bool CMSReplenishIntermediate = true {product}
uintx CMSRescanMultiple = 32 {product}
uintx CMSSamplingGrain = 16384 {product}
bool CMSScavengeBeforeRemark = false {product}
uintx CMSScheduleRemarkEdenPenetration = 50 {product}
uintx CMSScheduleRemarkEdenSizeThreshold = 2097152 {product}
uintx CMSScheduleRemarkSamplingRatio = 5 {product}
double CMSSmallCoalSurplusPercent = 1.050000 {product}
double CMSSmallSplitSurplusPercent = 1.100000 {product}
bool CMSSplitIndexedFreeListBlocks = true {product}
intx CMSTriggerInterval = -1 {manageable}
uintx CMSTriggerRatio = 80 {product}
intx CMSWaitDuration = 2000 {manageable}
uintx CMSWorkQueueDrainThreshold = 10 {product}
bool CMSYield = true {product}
uintx CMSYieldSleepCount = 0 {product}
uintx CMSYoungGenPerWorker = 67108864 {pd product}
uintx CMS_FLSPadding = 1 {product}
uintx CMS_FLSWeight = 75 {product}
uintx CMS_SweepPadding = 1 {product}
uintx CMS_SweepTimerThresholdMillis = 10 {product}
uintx CMS_SweepWeight = 75 {product}
bool CheckEndorsedAndExtDirs = false {product}
bool CheckJNICalls = false {product}
bool ClassUnloading = true {product}
bool ClassUnloadingWithConcurrentMark = true {product}
intx ClearFPUAtPark = 0 {product}
bool ClipInlining = true {product}
uintx CodeCacheExpansionSize = 65536 {pd product}
uintx CodeCacheMinimumFreeSpace = 512000 {product}
bool CollectGen0First = false {product}
bool CompactFields = true {product}
intx CompilationPolicyChoice = 3 {product}
ccstrlist CompileCommand = {product}
ccstr CompileCommandFile = {product}
ccstrlist CompileOnly = {product}
intx CompileThreshold = 10000 {pd product}
bool CompilerThreadHintNoPreempt = true {product}
intx CompilerThreadPriority = -1 {product}
intx CompilerThreadStackSize = 0 {pd product}
uintx CompressedClassSpaceSize = 1073741824 {product}
uintx ConcGCThreads = 0 {product}
intx ConditionalMoveLimit = 3 {C2 pd product}
intx ContendedPaddingWidth = 128 {product}
bool ConvertSleepToYield = true {pd product}
bool ConvertYieldToSleep = false {product}
bool CrashOnOutOfMemoryError = false {product}
bool CreateMinidumpOnCrash = false {product}
bool CriticalJNINatives = true {product}
bool DTraceAllocProbes = false {product}
bool DTraceMethodProbes = false {product}
bool DTraceMonitorProbes = false {product}
bool Debugging = false {product}
uintx DefaultMaxRAMFraction = 4 {product}
intx DefaultThreadPriority = -1 {product}
intx DeferPollingPageLoopCount = -1 {product}
intx DeferThrSuspendLoopCount = 4000 {product}
bool DeoptimizeRandom = false {product}
bool DisableAttachMechanism = false {product}
bool DisableExplicitGC = false {product}
bool DisplayVMOutputToStderr = false {product}
bool DisplayVMOutputToStdout = false {product}
bool DoEscapeAnalysis = true {C2 product}
bool DontCompileHugeMethods = true {product}
bool DontYieldALot = false {pd product}
ccstr DumpLoadedClassList = {product}
bool DumpReplayDataOnError = true {product}
bool DumpSharedSpaces = false {product}
bool EagerXrunInit = false {product}
intx EliminateAllocationArraySizeLimit = 64 {C2 product}
bool EliminateAllocations = true {C2 product}
bool EliminateAutoBox = true {C2 product}
bool EliminateLocks = true {C2 product}
bool EliminateNestedLocks = true {C2 product}
intx EmitSync = 0 {product}
bool EnableContended = true {product}
bool EnableResourceManagementTLABCache = true {product}
bool EnableSharedLookupCache = true {product}
bool EnableTracing = false {product}
uintx ErgoHeapSizeLimit = 0 {product}
ccstr ErrorFile = {product}
ccstr ErrorReportServer = {product}
double EscapeAnalysisTimeout = 20.000000 {C2 product}
bool EstimateArgEscape = true {product}
bool ExitOnOutOfMemoryError = false {product}
bool ExplicitGCInvokesConcurrent = false {product}
bool ExplicitGCInvokesConcurrentAndUnloadsClasses = false {product}
bool ExtendedDTraceProbes = false {product}
ccstr ExtraSharedClassListFile = {product}
bool FLSAlwaysCoalesceLarge = false {product}
uintx FLSCoalescePolicy = 2 {product}
double FLSLargestBlockCoalesceProximity = 0.990000 {product}
bool FailOverToOldVerifier = true {product}
bool FastTLABRefill = true {product}
intx FenceInstruction = 0 {ARCH product}
intx FieldsAllocationStyle = 1 {product}
bool FilterSpuriousWakeups = true {product}
ccstr FlightRecorderOptions = {product}
bool ForceNUMA = false {product}
bool ForceTimeHighResolution = false {product}
intx FreqInlineSize = 325 {pd product}
double G1ConcMarkStepDurationMillis = 10.000000 {product}
uintx G1ConcRSHotCardLimit = 4 {product}
uintx G1ConcRSLogCacheSize = 10 {product}
intx G1ConcRefinementGreenZone = 0 {product}
intx G1ConcRefinementRedZone = 0 {product}
intx G1ConcRefinementServiceIntervalMillis = 300 {product}
uintx G1ConcRefinementThreads = 0 {product}
intx G1ConcRefinementThresholdStep = 0 {product}
intx G1ConcRefinementYellowZone = 0 {product}
uintx G1ConfidencePercent = 50 {product}
uintx G1HeapRegionSize = 0 {product}
uintx G1HeapWastePercent = 5 {product}
uintx G1MixedGCCountTarget = 8 {product}
intx G1RSetRegionEntries = 0 {product}
uintx G1RSetScanBlockSize = 64 {product}
intx G1RSetSparseRegionEntries = 0 {product}
intx G1RSetUpdatingPauseTimePercent = 10 {product}
intx G1RefProcDrainInterval = 10 {product}
uintx G1ReservePercent = 10 {product}
uintx G1SATBBufferEnqueueingThresholdPercent = 60 {product}
intx G1SATBBufferSize = 1024 {product}
intx G1UpdateBufferSize = 256 {product}
bool G1UseAdaptiveConcRefinement = true {product}
uintx GCDrainStackTargetSize = 64 {product}
uintx GCHeapFreeLimit = 2 {product}
uintx GCLockerEdenExpansionPercent = 5 {product}
bool GCLockerInvokesConcurrent = false {product}
uintx GCLogFileSize = 8192 {product}
uintx GCPauseIntervalMillis = 0 {product}
uintx GCTaskTimeStampEntries = 200 {product}
uintx GCTimeLimit = 98 {product}
uintx GCTimeRatio = 99 {product}
uintx HeapBaseMinAddress = 2147483648 {pd product}
bool HeapDumpAfterFullGC = false {manageable}
bool HeapDumpBeforeFullGC = false {manageable}
bool HeapDumpOnOutOfMemoryError = false {manageable}
ccstr HeapDumpPath = {manageable}
uintx HeapFirstMaximumCompactionCount = 3 {product}
uintx HeapMaximumCompactionInterval = 20 {product}
uintx HeapSizePerGCThread = 87241520 {product}
bool IgnoreEmptyClassPaths = false {product}
bool IgnoreUnrecognizedVMOptions = false {product}
uintx IncreaseFirstTierCompileThresholdAt = 50 {product}
bool IncrementalInline = true {C2 product}
uintx InitialBootClassLoaderMetaspaceSize = 4194304 {product}
uintx InitialCodeCacheSize = 2555904 {pd product}
uintx InitialHeapSize := 104857600 {product}
uintx InitialRAMFraction = 64 {product}
double InitialRAMPercentage = 1.562500 {product}
uintx InitialSurvivorRatio = 8 {product}
uintx InitialTenuringThreshold = 7 {product}
uintx InitiatingHeapOccupancyPercent = 45 {product}
bool Inline = true {product}
ccstr InlineDataFile = {product}
intx InlineSmallCode = 2000 {pd product}
bool InlineSynchronizedMethods = true {C1 product}
bool InsertMemBarAfterArraycopy = true {C2 product}
intx InteriorEntryAlignment = 16 {C2 pd product}
intx InterpreterProfilePercentage = 33 {product}
bool JNIDetachReleasesMonitors = true {product}
bool JavaMonitorsInStackTrace = true {product}
intx JavaPriority10_To_OSPriority = -1 {product}
intx JavaPriority1_To_OSPriority = -1 {product}
intx JavaPriority2_To_OSPriority = -1 {product}
intx JavaPriority3_To_OSPriority = -1 {product}
intx JavaPriority4_To_OSPriority = -1 {product}
intx JavaPriority5_To_OSPriority = -1 {product}
intx JavaPriority6_To_OSPriority = -1 {product}
intx JavaPriority7_To_OSPriority = -1 {product}
intx JavaPriority8_To_OSPriority = -1 {product}
intx JavaPriority9_To_OSPriority = -1 {product}
bool LIRFillDelaySlots = false {C1 pd product}
uintx LargePageHeapSizeThreshold = 134217728 {product}
uintx LargePageSizeInBytes = 0 {product}
bool LazyBootClassLoader = true {product}
intx LiveNodeCountInliningCutoff = 40000 {C2 product}
bool LogCommercialFeatures = false {product}
intx LoopMaxUnroll = 16 {C2 product}
intx LoopOptsCount = 43 {C2 product}
intx LoopUnrollLimit = 60 {C2 pd product}
intx LoopUnrollMin = 4 {C2 product}
bool LoopUnswitching = true {C2 product}
bool ManagementServer = false {product}
uintx MarkStackSize = 4194304 {product}
uintx MarkStackSizeMax = 536870912 {product}
uintx MarkSweepAlwaysCompactCount = 4 {product}
uintx MarkSweepDeadRatio = 1 {product}
intx MaxBCEAEstimateLevel = 5 {product}
intx MaxBCEAEstimateSize = 150 {product}
uintx MaxDirectMemorySize = 0 {product}
bool MaxFDLimit = true {product}
uintx MaxGCMinorPauseMillis = 18446744073709551615 {product}
uintx MaxGCPauseMillis = 18446744073709551615 {product}
uintx MaxHeapFreeRatio = 100 {manageable}
uintx MaxHeapSize := 209715200 {product}
intx MaxInlineLevel = 9 {product}
intx MaxInlineSize = 35 {product}
intx MaxJNILocalCapacity = 65536 {product}
intx MaxJavaStackTraceDepth = 1024 {product}
intx MaxJumpTableSize = 65000 {C2 product}
intx MaxJumpTableSparseness = 5 {C2 product}
intx MaxLabelRootDepth = 1100 {C2 product}
intx MaxLoopPad = 11 {C2 product}
uintx MaxMetaspaceExpansion = 5451776 {product}
uintx MaxMetaspaceFreeRatio = 70 {product}
uintx MaxMetaspaceSize = 18446744073709547520 {product}
uintx MaxNewSize := 69730304 {product}
intx MaxNodeLimit = 75000 {C2 product}
uint64_t MaxRAM = 137438953472 {pd product}
uintx MaxRAMFraction = 4 {product}
double MaxRAMPercentage = 25.000000 {product}
intx MaxRecursiveInlineLevel = 1 {product}
uintx MaxTenuringThreshold = 15 {product}
intx MaxTrivialSize = 6 {product}
intx MaxVectorSize = 32 {C2 product}
uintx MetaspaceSize = 21807104 {pd product}
bool MethodFlushing = true {product}
uintx MinHeapDeltaBytes := 524288 {product}
uintx MinHeapFreeRatio = 0 {manageable}
intx MinInliningThreshold = 250 {product}
intx MinJumpTableSize = 10 {C2 pd product}
uintx MinMetaspaceExpansion = 339968 {product}
uintx MinMetaspaceFreeRatio = 40 {product}
uintx MinRAMFraction = 2 {product}
double MinRAMPercentage = 50.000000 {product}
uintx MinSurvivorRatio = 3 {product}
uintx MinTLABSize = 2048 {product}
intx MonitorBound = 0 {product}
bool MonitorInUseLists = false {product}
intx MultiArrayExpandLimit = 6 {C2 product}
bool MustCallLoadClassInternal = false {product}
uintx NUMAChunkResizeWeight = 20 {product}
uintx NUMAInterleaveGranularity = 2097152 {product}
uintx NUMAPageScanRate = 256 {product}
uintx NUMASpaceResizeRate = 1073741824 {product}
bool NUMAStats = false {product}
ccstr NativeMemoryTracking = off {product}
bool NeedsDeoptSuspend = false {pd product}
bool NeverActAsServerClassMachine = false {pd product}
bool NeverTenure = false {product}
uintx NewRatio = 2 {product}
uintx NewSize := 34603008 {product}
uintx NewSizeThreadIncrease = 5320 {pd product}
intx NmethodSweepActivity = 10 {product}
intx NmethodSweepCheckInterval = 5 {product}
intx NmethodSweepFraction = 16 {product}
intx NodeLimitFudgeFactor = 2000 {C2 product}
uintx NumberOfGCLogFiles = 0 {product}
intx NumberOfLoopInstrToAlign = 4 {C2 product}
intx ObjectAlignmentInBytes = 8 {lp64_product}
uintx OldPLABSize = 1024 {product}
uintx OldPLABWeight = 50 {product}
uintx OldSize := 70254592 {product}
bool OmitStackTraceInFastThrow = true {product}
ccstrlist OnError = {product}
ccstrlist OnOutOfMemoryError = {product}
intx OnStackReplacePercentage = 140 {pd product}
bool OptimizeFill = true {C2 product}
bool OptimizePtrCompare = true {C2 product}
bool OptimizeStringConcat = true {C2 product}
bool OptoBundling = false {C2 pd product}
intx OptoLoopAlignment = 16 {pd product}
bool OptoScheduling = false {C2 pd product}
uintx PLABWeight = 75 {product}
bool PSChunkLargeArrays = true {product}
intx ParGCArrayScanChunk = 50 {product}
uintx ParGCDesiredObjsFromOverflowList = 20 {product}
bool ParGCTrimOverflow = true {product}
bool ParGCUseLocalOverflow = false {product}
uintx ParallelGCBufferWastePct = 10 {product}
uintx ParallelGCThreads = 4 {product}
bool ParallelGCVerbose = false {product}
uintx ParallelOldDeadWoodLimiterMean = 50 {product}
uintx ParallelOldDeadWoodLimiterStdDev = 80 {product}
bool ParallelRefProcBalancingEnabled = true {product}
bool ParallelRefProcEnabled = false {product}
bool PartialPeelAtUnsignedTests = true {C2 product}
bool PartialPeelLoop = true {C2 product}
intx PartialPeelNewPhiDelta = 0 {C2 product}
uintx PausePadding = 1 {product}
intx PerBytecodeRecompilationCutoff = 200 {product}
intx PerBytecodeTrapLimit = 4 {product}
intx PerMethodRecompilationCutoff = 400 {product}
intx PerMethodTrapLimit = 100 {product}
bool PerfAllowAtExitRegistration = false {product}
bool PerfBypassFileSystemCheck = false {product}
intx PerfDataMemorySize = 32768 {product}
intx PerfDataSamplingInterval = 50 {product}
ccstr PerfDataSaveFile = {product}
bool PerfDataSaveToFile = false {product}
bool PerfDisableSharedMem = false {product}
intx PerfMaxStringConstLength = 1024 {product}
intx PreInflateSpin = 10 {pd product}
bool PreferInterpreterNativeStubs = false {pd product}
intx PrefetchCopyIntervalInBytes = 576 {product}
intx PrefetchFieldsAhead = 1 {product}
intx PrefetchScanIntervalInBytes = 576 {product}
bool PreserveAllAnnotations = false {product}
bool PreserveFramePointer = false {pd product}
uintx PretenureSizeThreshold = 0 {product}
bool PrintAdaptiveSizePolicy = false {product}
bool PrintCMSInitiationStatistics = false {product}
intx PrintCMSStatistics = 0 {product}
bool PrintClassHistogram = false {manageable}
bool PrintClassHistogramAfterFullGC = false {manageable}
bool PrintClassHistogramBeforeFullGC = false {manageable}
bool PrintCodeCache = false {product}
bool PrintCodeCacheOnCompilation = false {product}
bool PrintCommandLineFlags = false {product}
bool PrintCompilation = false {product}
bool PrintConcurrentLocks = false {manageable}
intx PrintFLSCensus = 0 {product}
intx PrintFLSStatistics = 0 {product}
bool PrintFlagsFinal := true {product}
bool PrintFlagsInitial = false {product}
bool PrintGC = false {manageable}
bool PrintGCApplicationConcurrentTime = false {product}
bool PrintGCApplicationStoppedTime = false {product}
bool PrintGCCause = true {product}
bool PrintGCDateStamps = false {manageable}
bool PrintGCDetails = false {manageable}
bool PrintGCID = false {manageable}
bool PrintGCTaskTimeStamps = false {product}
bool PrintGCTimeStamps = false {manageable}
bool PrintHeapAtGC = false {product rw}
bool PrintHeapAtGCExtended = false {product rw}
bool PrintHeapAtSIGBREAK = true {product}
bool PrintJNIGCStalls = false {product}
bool PrintJNIResolving = false {product}
bool PrintOldPLAB = false {product}
bool PrintOopAddress = false {product}
bool PrintPLAB = false {product}
bool PrintParallelOldGCPhaseTimes = false {product}
bool PrintPromotionFailure = false {product}
bool PrintReferenceGC = false {product}
bool PrintSafepointStatistics = false {product}
intx PrintSafepointStatisticsCount = 300 {product}
intx PrintSafepointStatisticsTimeout = -1 {product}
bool PrintSharedArchiveAndExit = false {product}
bool PrintSharedDictionary = false {product}
bool PrintSharedSpaces = false {product}
bool PrintStringDeduplicationStatistics = false {product}
bool PrintStringTableStatistics = false {product}
bool PrintTLAB = false {product}
bool PrintTenuringDistribution = false {product}
bool PrintTieredEvents = false {product}
bool PrintVMOptions = false {product}
bool PrintVMQWaitTime = false {product}
bool PrintWarnings = true {product}
uintx ProcessDistributionStride = 4 {product}
bool ProfileInterpreter = true {pd product}
bool ProfileIntervals = false {product}
intx ProfileIntervalsTicks = 100 {product}
intx ProfileMaturityPercentage = 20 {product}
bool ProfileVM = false {product}
bool ProfilerPrintByteCodeStatistics = false {product}
bool ProfilerRecordPC = false {product}
uintx PromotedPadding = 3 {product}
uintx QueuedAllocationWarningCount = 0 {product}
uintx RTMRetryCount = 5 {ARCH product}
bool RangeCheckElimination = true {product}
intx ReadPrefetchInstr = 0 {ARCH product}
bool ReassociateInvariants = true {C2 product}
bool ReduceBulkZeroing = true {C2 product}
bool ReduceFieldZeroing = true {C2 product}
bool ReduceInitialCardMarks = true {C2 product}
bool ReduceSignalUsage = false {product}
intx RefDiscoveryPolicy = 0 {product}
bool ReflectionWrapResolutionErrors = true {product}
bool RegisterFinalizersAtInit = true {product}
bool RelaxAccessControlCheck = false {product}
ccstr ReplayDataFile = {product}
bool RequireSharedSpaces = false {product}
uintx ReservedCodeCacheSize = 251658240 {pd product}
bool ResizeOldPLAB = true {product}
bool ResizePLAB = true {product}
bool ResizeTLAB = true {pd product}
bool RestoreMXCSROnJNICalls = false {product}
bool RestrictContended = true {product}
bool RewriteBytecodes = true {pd product}
bool RewriteFrequentPairs = false {pd product}
intx SafepointPollOffset = 256 {C1 pd product}
intx SafepointSpinBeforeYield = 2000 {product}
bool SafepointTimeout = false {product}
intx SafepointTimeoutDelay = 10000 {product}
bool ScavengeBeforeFullGC = true {product}
intx SelfDestructTimer = 0 {product}
uintx SharedBaseAddress = 34359738368 {product}
ccstr SharedClassListFile = {product}
uintx SharedMiscCodeSize = 122880 {product}
uintx SharedMiscDataSize = 4194304 {product}
uintx SharedReadOnlySize = 16777216 {product}
uintx SharedReadWriteSize = 16777216 {product}
bool ShowMessageBoxOnError = false {product}
intx SoftRefLRUPolicyMSPerMB = 1000 {product}
bool SpecialEncodeISOArray = true {C2 product}
bool SplitIfBlocks = true {C2 product}
intx StackRedPages = 1 {pd product}
intx StackShadowPages = 20 {pd product}
bool StackTraceInThrowable = true {product}
intx StackYellowPages = 2 {pd product}
bool StartAttachListener = false {product}
intx StarvationMonitorInterval = 200 {product}
bool StressLdcRewrite = false {product}
uintx StringDeduplicationAgeThreshold = 3 {product}
uintx StringTableSize = 60013 {product}
bool SuppressFatalErrorMessage = false {product}
uintx SurvivorPadding = 3 {product}
uintx SurvivorRatio = 8 {product}
intx SuspendRetryCount = 50 {product}
intx SuspendRetryDelay = 5 {product}
intx SyncFlags = 0 {product}
ccstr SyncKnobs = {product}
intx SyncVerbose = 0 {product}
uintx TLABAllocationWeight = 35 {product}
uintx TLABRefillWasteFraction = 64 {product}
uintx TLABSize = 0 {product}
bool TLABStats = true {product}
uintx TLABWasteIncrement = 4 {product}
uintx TLABWasteTargetPercent = 1 {product}
uintx TargetPLABWastePct = 10 {product}
uintx TargetSurvivorRatio = 50 {product}
uintx TenuredGenerationSizeIncrement = 20 {product}
uintx TenuredGenerationSizeSupplement = 80 {product}
uintx TenuredGenerationSizeSupplementDecay = 2 {product}
intx ThreadPriorityPolicy = 0 {product}
bool ThreadPriorityVerbose = false {product}
uintx ThreadSafetyMargin = 52428800 {product}
intx ThreadStackSize = 1024 {pd product}
uintx ThresholdTolerance = 10 {product}
intx Tier0BackedgeNotifyFreqLog = 10 {product}
intx Tier0InvokeNotifyFreqLog = 7 {product}
intx Tier0ProfilingStartPercentage = 200 {product}
intx Tier23InlineeNotifyFreqLog = 20 {product}
intx Tier2BackEdgeThreshold = 0 {product}
intx Tier2BackedgeNotifyFreqLog = 14 {product}
intx Tier2CompileThreshold = 0 {product}
intx Tier2InvokeNotifyFreqLog = 11 {product}
intx Tier3BackEdgeThreshold = 60000 {product}
intx Tier3BackedgeNotifyFreqLog = 13 {product}
intx Tier3CompileThreshold = 2000 {product}
intx Tier3DelayOff = 2 {product}
intx Tier3DelayOn = 5 {product}
intx Tier3InvocationThreshold = 200 {product}
intx Tier3InvokeNotifyFreqLog = 10 {product}
intx Tier3LoadFeedback = 5 {product}
intx Tier3MinInvocationThreshold = 100 {product}
intx Tier4BackEdgeThreshold = 40000 {product}
intx Tier4CompileThreshold = 15000 {product}
intx Tier4InvocationThreshold = 5000 {product}
intx Tier4LoadFeedback = 3 {product}
intx Tier4MinInvocationThreshold = 600 {product}
bool TieredCompilation = true {pd product}
intx TieredCompileTaskTimeout = 50 {product}
intx TieredRateUpdateMaxTime = 25 {product}
intx TieredRateUpdateMinTime = 1 {product}
intx TieredStopAtLevel = 4 {product}
bool TimeLinearScan = false {C1 product}
bool TraceBiasedLocking = false {product}
bool TraceClassLoading = false {product rw}
bool TraceClassLoadingPreorder = false {product}
bool TraceClassPaths = false {product}
bool TraceClassResolution = false {product}
bool TraceClassUnloading = false {product rw}
bool TraceDynamicGCThreads = false {product}
bool TraceGen0Time = false {product}
bool TraceGen1Time = false {product}
ccstr TraceJVMTI = {product}
bool TraceLoaderConstraints = false {product rw}
bool TraceMetadataHumongousAllocation = false {product}
bool TraceMonitorInflation = false {product}
bool TraceParallelOldGCTasks = false {product}
intx TraceRedefineClasses = 0 {product}
bool TraceSafepointCleanupTime = false {product}
bool TraceSharedLookupCache = false {product}
bool TraceSuspendWaitFailures = false {product}
intx TrackedInitializationLimit = 50 {C2 product}
bool TransmitErrorReport = false {product}
bool TrapBasedNullChecks = false {pd product}
bool TrapBasedRangeChecks = false {C2 pd product}
intx TypeProfileArgsLimit = 2 {product}
uintx TypeProfileLevel = 111 {pd product}
intx TypeProfileMajorReceiverPercent = 90 {C2 product}
intx TypeProfileParmsLimit = 2 {product}
intx TypeProfileWidth = 2 {product}
intx UnguardOnExecutionViolation = 0 {product}
bool UnlinkSymbolsALot = false {product}
bool Use486InstrsOnly = false {ARCH product}
bool UseAES = true {product}
bool UseAESIntrinsics = true {product}
intx UseAVX = 2 {ARCH product}
bool UseAdaptiveGCBoundary = false {product}
bool UseAdaptiveGenerationSizePolicyAtMajorCollection = true {product}
bool UseAdaptiveGenerationSizePolicyAtMinorCollection = true {product}
bool UseAdaptiveNUMAChunkSizing = true {product}
bool UseAdaptiveSizeDecayMajorGCCost = true {product}
bool UseAdaptiveSizePolicy = true {product}
bool UseAdaptiveSizePolicyFootprintGoal = true {product}
bool UseAdaptiveSizePolicyWithSystemGC = false {product}
bool UseAddressNop = true {ARCH product}
bool UseAltSigs = false {product}
bool UseAutoGCSelectPolicy = false {product}
bool UseBMI1Instructions = true {ARCH product}
bool UseBMI2Instructions = true {ARCH product}
bool UseBiasedLocking = true {product}
bool UseBimorphicInlining = true {C2 product}
bool UseBoundThreads = true {product}
bool UseBsdPosixThreadCPUClocks = true {product}
bool UseCLMUL = true {ARCH product}
bool UseCMSBestFit = true {product}
bool UseCMSCollectionPassing = true {product}
bool UseCMSCompactAtFullCollection = true {product}
bool UseCMSInitiatingOccupancyOnly = false {product}
bool UseCRC32Intrinsics = true {product}
bool UseCodeCacheFlushing = true {product}
bool UseCompiler = true {product}
bool UseCompilerSafepoints = true {product}
bool UseCompressedClassPointers := true {lp64_product}
bool UseCompressedOops := true {lp64_product}
bool UseConcMarkSweepGC = false {product}
bool UseCondCardMark = false {C2 product}
bool UseCountLeadingZerosInstruction = true {ARCH product}
bool UseCountTrailingZerosInstruction = true {ARCH product}
bool UseCountedLoopSafepoints = false {C2 product}
bool UseCounterDecay = true {product}
bool UseDivMod = true {C2 product}
bool UseDynamicNumberOfGCThreads = false {product}
bool UseFPUForSpilling = true {C2 product}
bool UseFastAccessorMethods = false {product}
bool UseFastEmptyMethods = false {product}
bool UseFastJNIAccessors = true {product}
bool UseFastStosb = true {ARCH product}
bool UseG1GC = false {product}
bool UseGCLogFileRotation = false {product}
bool UseGCOverheadLimit = true {product}
bool UseGCTaskAffinity = false {product}
bool UseHeavyMonitors = false {product}
bool UseHugeTLBFS = false {product}
bool UseInlineCaches = true {product}
bool UseInterpreter = true {product}
bool UseJumpTables = true {C2 product}
bool UseLWPSynchronization = true {product}
bool UseLargePages = false {pd product}
bool UseLargePagesInMetaspace = false {product}
bool UseLargePagesIndividualAllocation = false {pd product}
bool UseLockedTracing = false {product}
bool UseLoopCounter = true {product}
bool UseLoopInvariantCodeMotion = true {C1 product}
bool UseLoopPredicate = true {C2 product}
bool UseMathExactIntrinsics = true {C2 product}
bool UseMaximumCompactionOnSystemGC = true {product}
bool UseMembar = true {pd product}
bool UseMontgomeryMultiplyIntrinsic = true {C2 product}
bool UseMontgomerySquareIntrinsic = true {C2 product}
bool UseMulAddIntrinsic = true {C2 product}
bool UseMultiplyToLenIntrinsic = true {C2 product}
bool UseNUMA = false {product}
bool UseNUMAInterleaving = false {product}
bool UseNewLongLShift = false {ARCH product}
bool UseOSErrorReporting = false {pd product}
bool UseOldInlining = true {C2 product}
bool UseOnStackReplacement = true {pd product}
bool UseOnlyInlinedBimorphic = true {C2 product}
bool UseOprofile = false {product}
bool UseOptoBiasInlining = true {C2 product}
bool UsePSAdaptiveSurvivorSizePolicy = true {product}
bool UseParNewGC = false {product}
bool UseParallelGC := true {product}
bool UseParallelOldGC = true {product}
bool UsePerfData = true {product}
bool UsePopCountInstruction = true {product}
bool UseRDPCForConstantTableBase = false {C2 product}
bool UseRTMDeopt = false {ARCH product}
bool UseRTMLocking = false {ARCH product}
bool UseSHA = false {product}
bool UseSHA1Intrinsics = false {product}
bool UseSHA256Intrinsics = false {product}
bool UseSHA512Intrinsics = false {product}
bool UseSHM = false {product}
intx UseSSE = 4 {product}
bool UseSSE42Intrinsics = true {product}
bool UseSerialGC = false {product}
bool UseSharedSpaces = false {product}
bool UseSignalChaining = true {product}
bool UseSquareToLenIntrinsic = true {C2 product}
bool UseStoreImmI16 = false {ARCH product}
bool UseStringDeduplication = false {product}
bool UseSuperWord = true {C2 product}
bool UseTLAB = true {pd product}
bool UseThreadPriorities = true {pd product}
bool UseTypeProfile = true {product}
bool UseTypeSpeculation = true {C2 product}
bool UseUnalignedLoadStores = true {ARCH product}
bool UseVMInterruptibleIO = false {product}
bool UseXMMForArrayCopy = true {product}
bool UseXmmI2D = false {ARCH product}
bool UseXmmI2F = false {ARCH product}
bool UseXmmLoadAndClearUpper = true {ARCH product}
bool UseXmmRegToRegMoveAll = true {ARCH product}
bool VMThreadHintNoPreempt = false {product}
intx VMThreadPriority = -1 {product}
intx VMThreadStackSize = 1024 {pd product}
intx ValueMapInitialSize = 11 {C1 product}
intx ValueMapMaxLoopSize = 8 {C1 product}
intx ValueSearchLimit = 1000 {C2 product}
bool VerifyMergedCPBytecodes = true {product}
bool VerifySharedSpaces = false {product}
intx WorkAroundNPTLTimedWaitHang = 1 {product}
uintx YoungGenerationSizeIncrement = 20 {product}
uintx YoungGenerationSizeSupplement = 80 {product}
uintx YoungGenerationSizeSupplementDecay = 8 {product}
uintx YoungPLABSize = 4096 {product}
bool ZeroTLAB = false {product}
intx hashCode = 5 {product}
Connected to the target VM, address: '127.0.0.1:64801', transport: 'socket'
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.1.6.RELEASE)
2020-03-11 16:33:04.786 INFO 21370 --- [ main] c.gaoxinfu.demo.jvm.DemoJvmApplication : Starting DemoJvmApplication on localhost with PID 21370 (/Users/gaoxinfu/demo-idea/demo-jdk/demo-jvm/target/classes started by gaoxinfu in /Users/gaoxinfu/demo-idea/demo-jdk)
2020-03-11 16:33:04.808 INFO 21370 --- [ main] c.gaoxinfu.demo.jvm.DemoJvmApplication : No active profile set, falling back to default profiles: default
2020-03-11 16:33:07.294 INFO 21370 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8080 (http)
2020-03-11 16:33:07.343 INFO 21370 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2020-03-11 16:33:07.344 INFO 21370 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/9.0.21]
2020-03-11 16:33:07.503 INFO 21370 --- [ main] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2020-03-11 16:33:07.507 INFO 21370 --- [ main] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 2505 ms
2020-03-11 16:33:07.784 INFO 21370 --- [ main] o.s.s.concurrent.ThreadPoolTaskExecutor : Initializing ExecutorService 'applicationTaskExecutor'
2020-03-11 16:33:08.084 INFO 21370 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8080 (http) with context path ''
2020-03-11 16:33:08.098 INFO 21370 --- [ main] c.gaoxinfu.demo.jvm.DemoJvmApplication : Started DemoJvmApplication in 3.923 seconds (JVM running for 4.85
4.1.3.驗證：如下驗證成功，被修改參數前面都有一個冒號
4.1.4.備註：上面的單位都是字節byte
1k=1024byte字節
1MB=1024K
1GB=1024MB
5.常用參數彙總說明
| 參數 | 含義 | 說明 |
|---|---|---|
| -XX:CICompilerCount=3 | 最大並行編譯數 | 如果設置大於1，雖然編譯速度會提高，但是同樣影響系統穩定性，會增加JVM崩潰的可能 |
| -XX:InitialHeapSize=100M | 初始化堆大小 | 簡寫-Xms100M |
| -XX:MaxHeapSize=100M | 最大堆大小 | 簡寫-Xmx100M |
| -XX:NewSize=20M | 設置年輕代的大小 | |
| -XX:MaxNewSize=50M | 年輕代最大大小 | |
| -XX:OldSize=50M | 設置老年代大小 | |
| -XX:MetaspaceSize=50M | 設置方法區大小 | |
| -XX:MaxMetaspaceSize=50M | 方法區最大大小 | |
| -XX:+UseParallelGC | 使用UseParallelGC | 新生代，吞吐量優先 |
| -XX:+UseParallelOldGC | 使用UseParallelOldGC | 老年代，吞吐量優先 |
| -XX:+UseConcMarkSweepGC | 使用CMS | 老年代，停頓時間優先 |
| -XX:+UseG1GC | 使用G1GC | 新生代，老年代，停頓時間優先 |
| -XX:NewRatio | 新老生代的比值 | 比如-XX:Ratio=4，則表示新生代:老年代=1:4，也就是新生代佔整個堆內存的1/5 |
| -XX:SurvivorRatio | 兩個S區和Eden區的比值 | 比如-XX:SurvivorRatio=8，也就是(S0+S1):Eden=2:8， 也就是一個S佔整個新生代的1/10 |
| -XX:+HeapDumpOnOutOfMemoryError | 啓動堆內存溢出打印 | 當JVM堆內存發生溢出時，也就是OOM，自動生成dump文件 |
| -XX:HeapDumpPath=heap.hprof | 指定堆內存溢出打印目錄 | 表示在當前目錄生成一個heap.hprof文件 |
| XX:+PrintGCDetails - XX:+PrintGCTimeStamps - XX:+PrintGCDateStamps Xloggc:$CATALINA_HOME/logs/gc.log | 打印出GC日誌 | 可以使用不同的垃圾收集器，對比查看GC情況 |
| -Xss128k | 設置每個線程的堆棧大小 | 經驗值是3000-5000最佳 |
| -XX:MaxTenuringThreshold=6 | 提升年老代的最大臨界值 | 默認值爲 15 |
| G1之類的垃圾收集器用它來觸發併發GC週期,基於整個堆的使用率,而不只是某一代內存的使用比. 值爲 0 則表 | ||
| -XX:InitiatingHeapOccupancyPercent | 啓動併發GC週期時堆內存使用佔比 | 示”一直執行GC循環”. 默認值爲 45. |
| -XX:G1HeapWastePercent | 允許的浪費堆空間的佔比 | 默認是10%，如果併發標記可回收的空間小於10%,則不會觸發MixedGC。 |
| -XX:MaxGCPauseMillis=200ms | G1最大停頓時間 | 暫停時間不能太小，太小的話就會導致出現G1跟不上垃圾產生的速度。最終退化成Full GC。 所以對這個參數的調優是一個持續的過程，逐步調整到最佳狀態。 |
| -XX:ConcGCThreads=n | 併發垃圾收集器使用的線程數量 | 默認值隨JVM運行的平臺不同而不同 |
| -XX:G1MixedGCLiveThresholdPercent=65 | 混合垃圾回收週期中要包括的舊區域設置佔用率閾值 | 默認佔用率爲 65% |
| -XX:G1MixedGCCountTarget=8 | 設置標記週期完成後，對存活數據上限爲G1MixedGCLIveThresholdPercent 的舊區域執行混合垃圾回收的目標次數 | 默認8次混合垃圾回收，混合回收的目標是要控制在此目 標次數以內 |