Performance Tuning -- 09 -- Btrace应用示例

原文链接：Performance Tuning – 09 – Btrace应用示例

这里主要展示些 Btrace 相关的应用示例

一、拦截简单参数

监控方法

@RestController
public class HelloController {

    /**
     *  拦截简单参数
     */
    @GetMapping(value = "/arg/simple/{name}")
    public String argSimple(@PathVariable("name") String name) {
        return "Hello " + name + "!";
    }
}

Btrace 脚本

@BTrace
public class PrintArgSimple {

    @OnMethod(clazz = "com.xj.controller.HelloController", method = "argSimple")
    public static void test(@ProbeClassName String pcn, @ProbeMethodName String pmn, AnyType[] args) {
        BTraceUtils.printArray(args);
        BTraceUtils.println(pcn + " , " + pmn);
        BTraceUtils.println();
    }
}

@ProbeClassName
- 标记一个参数，用于保存目标类的类名
@ProbeMethodName
- 标记一个参数，用于保存目标方法的方法名
AnyType
- 表示任何类型的参数

调用接口
```
http://localhost:9998/arg/simple/World
```

监控输出

[World, ]
com.xj.controller.HelloController , argSimple

二、拦截返回值

监控方法

@RestController
public class HelloController {

    /**
     *  拦截返回值
     */
    @GetMapping(value = "/arg/simple/{name}")
    public String argSimple(@PathVariable("name") String name) {
        return "Hello " + name + "!";
    }
}

Btrace 脚本

@BTrace
public class PrintReturn {

    @OnMethod(clazz = "com.xj.controller.HelloController", 
              method = "argSimple", 
              location = @Location(Kind.RETURN))
    public static void test(@ProbeClassName String pcn, @ProbeMethodName String pmn, @Return AnyType result) {
        BTraceUtils.println(pcn + " , " + pmn + " , " + result);
        BTraceUtils.println();
    }
}

@Return
- 标记一个参数，用于保存返回值

调用接口
```
http://localhost:9998/arg/simple/World
```

监控输出

com.xj.controller.HelloController , argSimple , Hello World!

三、拦截构造函数

监控方法

@Data
public class User {

    private int id;
    private String name;

    public User(int id, String name) {
        this.id = id;
        this.name = name;
    }
}

@RestController
public class HelloController {

    /**
     *  拦截构造函数
     */
    @GetMapping(value = "/constructor")
    public User constructor(User user) {
        return user;
    }
}

Btrace 脚本

@BTrace
public class PrintConstructor {

    @OnMethod(clazz = "com.xj.entity.User", method = "<init>")
    public static void test(@ProbeClassName String pcn, @ProbeMethodName String pmn, AnyType[] args) {
        BTraceUtils.printArray(args);
        BTraceUtils.println(pcn + " , " + pmn);
        BTraceUtils.println();
    }
}

目标类为 User 类，目标方法为 <init> 方法 (构造方法在字节码层面显示为 <init>)

调用接口

http://localhost:9998/constructor?id=1&name=小明

监控输出

[1, 小明, ]
com.xj.entity.User , <init>

四、拦截同名函数

监控方法

@RestController
public class HelloController {

    /**
     *  拦截同名函数
     */
    @GetMapping(value = "/same1/{name}")
    public String same(@PathVariable("name") String name) {
        return "Hello " + name + "!";
    }

    /**
     *  拦截同名函数
     */
    @GetMapping(value = "/same2/{name}/{id}")
    public String same(@PathVariable("name") String name, @PathVariable(name = "id") int id) {
        return "Hello " + name + " " + id + "!";
    }
}

Btrace 脚本

@BTrace
public class PrintSame1 {

    @OnMethod(clazz = "com.xj.controller.HelloController", method = "same")
    public static void test(@ProbeClassName String pcn, @ProbeMethodName String pmn, String name) {
        BTraceUtils.println(pcn + " , " + pmn + " , " + name);
        BTraceUtils.println();
    }
}

@BTrace
public class PrintSame2 {

    @OnMethod(clazz = "com.xj.controller.HelloController", method = "same")
    public static void test(@ProbeClassName String pcn, @ProbeMethodName String pmn, String name, int id) {
        BTraceUtils.println(pcn + " , " + pmn + " , " + name + " , " + id);
        BTraceUtils.println();
    }
}

同名方法可以用真实参数进行区分

调用接口

http://localhost:9998/same1/World

http://localhost:9998/same2/World/1

监控输出

com.xj.controller.HelloController , same , World

com.xj.controller.HelloController , same , World , 1

五、拦截异常

监控方法

@RestController
public class HelloController {

    /**
     *  拦截异常
     */
    @GetMapping(value = "/exception")
    public String exception() {
        try {
            System.out.println("method start");
            System.out.println(1 / 0);
            System.out.println("method end");
        } catch (Exception e) {
            // 把异常吞了
        }
        return "success";
    }
}

Btrace 脚本

@BTrace 
public class PrintOnThrow {    
    // store current exception in a thread local
    // variable (@TLS annotation). Note that we can't
    // store it in a global variable!
    @TLS 
    static Throwable currentException;

    // introduce probe into every constructor of java.lang.Throwable
    // class and store "this" in the thread local variable.
    @OnMethod(
        clazz="java.lang.Throwable",
        method="<init>"
    )
    public static void onthrow(@Self Throwable self) {//new Throwable()
        currentException = self;
    }

    @OnMethod(
        clazz="java.lang.Throwable",
        method="<init>"
    )
    public static void onthrow1(@Self Throwable self, String s) {//new Throwable(String msg)
        currentException = self;
    }

    @OnMethod(
        clazz="java.lang.Throwable",
        method="<init>"
    )
    public static void onthrow1(@Self Throwable self, String s, Throwable cause) {//new Throwable(String msg, Throwable cause)
        currentException = self;
    }

    @OnMethod(
        clazz="java.lang.Throwable",
        method="<init>"
    )
    public static void onthrow2(@Self Throwable self, Throwable cause) {//new Throwable(Throwable cause)
        currentException = self;
    }

    // when any constructor of java.lang.Throwable returns
    // print the currentException's stack trace.
    @OnMethod(
        clazz="java.lang.Throwable",
        method="<init>",
        location=@Location(Kind.RETURN)
    )
    public static void onthrowreturn() {
        if (currentException != null) {
        	BTraceUtils.Threads.jstack(currentException);
            currentException = null;
        }
    }
}

当方法内部抛出的异常被吞掉时，我们可以用该 Btrace 脚本来检测被吞掉的异常

调用接口
```
http://localhost:9998/exception
```

监控输出

java.lang.ArithmeticException: / by zero
	com.xj.controller.HelloController.exception(HelloController.java:57)
	sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	java.lang.reflect.Method.invoke(Method.java:498)
	org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)
	org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
	org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
	org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:892)
	org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:797)
	org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
	org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1039)
	org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942)
	org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1005)
	org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:897)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:634)
	org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:882)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
	org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
	org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
	org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99)
	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:118)
	org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:92)
	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:118)
	org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93)
	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:118)
	org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)
	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:118)
	org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)
	org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
	org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490)
	org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
	org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
	org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
	org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
	org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408)
	org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
	org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:853)
	org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1587)
	org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
	java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	java.lang.Thread.run(Thread.java:748)

六、拦截行号

监控方法

@RestController
public class HelloController {

    /**
     *  拦截行号
     */
    @GetMapping(value = "/line")
    public String line() {
        System.out.println("line");
        return "success";
    }
}

Btrace 脚本

@BTrace
public class PrintLine {

    @OnMethod(clazz = "com.xj.controller.HelloController", 
              location = @Location(value = Kind.LINE, line = 70))
    public static void test(@ProbeClassName String pcn, @ProbeMethodName String pmn, int line) {
        BTraceUtils.println(pcn + " , " + pmn + " , " + line);
        BTraceUtils.println();
    }
}

Kind.LINE
- 在某一行进行拦截

调用接口
```
http://localhost:9998/line
```

监控输出

com.xj.controller.HelloController , line , 70

七、拦截复杂参数

监控方法

@RestController
public class HelloController {
    
    /**
     * 拦截复杂参数
     */
    @GetMapping(value = "/arg/complex")
    public User argComplex(User user) {
        return user;
    }
}

Btrace 脚本

@BTrace
public class PrintArgComplex {

    @OnMethod(clazz = "com.xj.controller.HelloController", method = "argComplex")
    public static void test(@ProbeClassName String pcn, @ProbeMethodName String pmn, User user) {
        // print all fields
        BTraceUtils.printFields(user);
        // print one field
        Field field = BTraceUtils.field("com.xj.entity.User", "name");
        BTraceUtils.println(BTraceUtils.get(field, user));
        BTraceUtils.println(pcn + " , " + pmn);
        BTraceUtils.println();
    }
}

由于此处我们引用了 User 类，则需要将目标程序中的 User 类加入到 classpath 中

使用 Class

btrace -cp D:\Workspace\Idea\idea-exercise-maven\jvm-tuning\target\classes 8664 PrintArgComplex.java

使用 jar 包 (注意：此处 jar 包须为普通 jar 包，而不是可执行 jar 包)

btrace -cp D:\Workspace\Idea\idea-exercise-maven\jvm-tuning\target\jvm-tuning-0.0.1-SNAPSHOT.jar 8664 PrintArgComplex.java

调用接口

http://localhost:9998/arg/complex?id=1&name=小明

监控输出

{id=1, name=小明, }
小明
com.xj.controller.HelloController , argComplex

八、打印参数

Btrace 脚本

@BTrace
public class PrintJInfo {

    static {
        BTraceUtils.println("System Properties:");
        BTraceUtils.printProperties();
        BTraceUtils.println("VM Flags");
        BTraceUtils.printVmArguments();
        BTraceUtils.println("OS Environment");
        BTraceUtils.printEnv();
        BTraceUtils.exit(0);
    }
}

可以在静态代码块中打印出系统参数、JVM 参数以及环境变量，类似于 jinfo

监控输出

System Properties:
sun.desktop = windows
awt.toolkit = sun.awt.windows.WToolkit
file.encoding.pkg = sun.io
java.specification.version = 1.8
sun.cpu.isalist = amd64
sun.jnu.encoding = GBK
com.sun.management.jmxremote.authenticate = false
// ...

九、正则表达式匹配

监控方法

@RestController
public class HelloController {

    /**
     *  拦截简单参数
     */
    @GetMapping(value = "/arg/simple/{name}")
    public String argSimple(@PathVariable("name") String name) {
        return "Hello " + name + "!";
    }
}

Btrace 脚本

@BTrace
public class PrintRegex {

    @OnMethod(clazz = "com.xj.controller.HelloController", method = "/.*/")
    public static void test(@ProbeClassName String pcn, @ProbeMethodName String pmn) {
        BTraceUtils.println(pcn + " , " + pmn);
        BTraceUtils.println();
    }
}

在 method 参数中，我们可以通过正则表达式来匹配相应的方法名 (此处 .* 代表匹配所有方法)

调用接口
```
http://localhost:9998/arg/simple/World
```

监控输出

[World, ]
com.xj.controller.HelloController , argSimple

posted @ 2020-05-27 10:54 GeneXu 阅读(113) 评论(0) 收藏举报

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Gene Xu

个人博客 https://blog.xujun.pro/

Performance Tuning -- 09 -- Btrace应用示例

一、拦截简单参数

二、拦截返回值

三、拦截构造函数

四、拦截同名函数

五、拦截异常

六、拦截行号

七、拦截复杂参数

八、打印参数

九、正则表达式匹配

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