Arthas 关于方法调用命令实战

「爱情、让人受尽委屈。」 2022-09-10 04:16 283阅读 0赞

# 一 点睛 #

> 1 monitor 方法执行监控，调用次数、执行时间、失败率
> 
> \-c 统计周期，默认值为120秒
> 
> 2 watch 方法执行观测，能观察到的范围为：返回值、抛出异常、入参，通过编写 groovy 表达式进行对应变量的查看
> 
> \-b 在方法调用之前观察(默认关闭)
> 
> \-e 在方法异常之后观察(默认关闭)
> 
> \-s 在方法返回之后观察(默认关闭)
> 
> \-f 在方法结束之后(正常返回和异常返回)观察(默认开启)
> 
> \-x 指定输岀结果的属性遍历深度,默认为0
> 
> 3 trace 方法内部调用路径,并输出方法路径上的每个节点上耗时
> 
> \-n 执行次数限制
> 
> 4 stack 输出当前方法被调用的调用路径
> 
> 5 tt 方法执行数据的时空隧道,记录下指定方法每次调用的入参和返回信息,并能对这些不同的时间下调用进行观测

# 二 代码 #

package chapter03;
    
    import java.util.ArrayList;
    import java.util.Random;
    
    /**
    * -Xms600m -Xmx600m -XX:SurvivorRatio=8
    * 老年代：400m
    * 伊甸园：160m
    * s0:20m
    * s1:20m
    */
    public class OOMTest {
        public static void main(String[] args) {
            ArrayList<Picture> list = new ArrayList<>();
            while (true) {
                try {
                    Thread.sleep(50);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                list.add(new Picture(new Random().nextInt(100 * 50)));
            }
        }
    }
    
    class Picture {
        private byte[] pixels;
    
    
        public Picture(int length) {
            this.pixels = new byte[length];
        }
    }

# 三 windows下进入命令界面 #

D:\ProgramFiles\arthas-packaging-3.5.4-bin>jps
    10656 Jps
    12736 Launcher
    2864
    10668 OOMTest
    
    D:\ProgramFiles\arthas-packaging-3.5.4-bin>as.bat 10668
    环境变量 JAVA_TOOL_OPTIONS 没有定义
    JAVA_HOME: D:\ProgramFiles\Java\jdk1.8.0_251
    telnet port: 3658
    http port: 8563
    信息: 用提供的模式无法找到文件。
    telnet wasn't found, please google how to install telnet under windows.
    Try to visit http://127.0.0.1:8563 to connecto arthas server.

# 四 实战 #

# monitor：每隔5秒打印一次方法执行情况
    [arthas@16852]$ monitor -c 5 chapter03.Picture <init>
    Press Q or Ctrl+C to abort.
    Affect(class count: 1 , method count: 1) cost in 98 ms, listenerId: 3
    timestamp                    class                                      method                                     total         success        fail          avg-rt(ms)     fail-rate
    -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
    2021-09-04 14:00:24          chapter03.Picture                          <init>                                     77            77             0             0.05           0.00%
    
    
    timestamp                    class                                      method                                     total         success        fail          avg-rt(ms)     fail-rate
    -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
    2021-09-04 14:00:29          chapter03.Picture                          <init>                                     79            79             0             0.02           0.00%
    
    
    timestamp                    class                                      method                                     total         success        fail          avg-rt(ms)     fail-rate
    -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
    2021-09-04 14:00:34          chapter03.Picture  
    
    # watch 方法执行观测，能观察到的范围为：返回值、抛出异常、入参
    [arthas@16852]$ watch chapter03.Picture <init>
    method=chapter03.Picture.<init> location=AtExit
    ts=2021-09-04 14:03:18; [cost=0.0176ms] result=@ArrayList[
        @Object[][isEmpty=false;size=1],
        @Picture[chapter03.Picture@4d76f3f8],
        null,
    ]
    method=chapter03.Picture.<init> location=AtExit
    ts=2021-09-04 14:03:18; [cost=0.0184ms] result=@ArrayList[
        @Object[][isEmpty=false;size=1],
        @Picture[chapter03.Picture@2d8e6db6],
        null,
    ]
    
    # 关注返回参数和结果 -x：返回深度 这里为2
    [arthas@16852]$ watch chapter03.Picture <init> "{params,returnObj}" -x 2
    method=chapter03.Picture.<init> location=AtExit
    ts=2021-09-04 14:06:50; [cost=0.0157ms] result=@ArrayList[
        @Object[][
            @Integer[2930],
        ],
        null,
    ]
    method=chapter03.Picture.<init> location=AtExit
    ts=2021-09-04 14:06:50; [cost=0.0202ms] result=@ArrayList[
        @Object[][
            @Integer[2113],
        ],
        null,
    ]
    Command execution times exceed limit: 100, so command will exit. You can set it with -n option.
    
    # 默认深度为1
    [arthas@16852]$ watch chapter03.Picture <init> "{params,returnObj}"
    method=chapter03.Picture.<init> location=AtExit
    ts=2021-09-04 14:09:43; [cost=0.0197ms] result=@ArrayList[
        @Object[][isEmpty=false;size=1],
        null,
    ]
    method=chapter03.Picture.<init> location=AtExit
    ts=2021-09-04 14:09:43; [cost=0.0298ms] result=@ArrayList[
        @Object[][isEmpty=false;size=1],
        null,
    ]
    Command execution times exceed limit: 100, so command will exit. You can set it with -n option.
    
    # trace 方法内部调用路径,并输出方法路径上的每个节点上耗时
    [arthas@16852]$ trace chapter03.Picture <init>
    `---ts=2021-09-04 14:11:50;thread_name=main;id=1;is_daemon=false;priority=5;TCCL=sun.misc.Launcher$AppClassLoader@18b4aac2
        `---[0.0125ms] chapter03.Picture:<init>()
    
    `---ts=2021-09-04 14:11:50;thread_name=main;id=1;is_daemon=false;priority=5;TCCL=sun.misc.Launcher$AppClassLoader@18b4aac2
        `---[0.0146ms] chapter03.Picture:<init>()
    
    # -n：限定执行次数，这里是 5次
    [arthas@16852]$ trace -n 5 chapter03.Picture <init>
    Press Q or Ctrl+C to abort.
    Affect(class count: 1 , method count: 1) cost in 38 ms, listenerId: 8
    `---ts=2021-09-04 14:15:41;thread_name=main;id=1;is_daemon=false;priority=5;TCCL=sun.misc.Launcher$AppClassLoader@18b4aac2
        `---[0.1016ms] chapter03.Picture:<init>()
    
    `---ts=2021-09-04 14:15:41;thread_name=main;id=1;is_daemon=false;priority=5;TCCL=sun.misc.Launcher$AppClassLoader@18b4aac2
        `---[0.0088ms] chapter03.Picture:<init>()
    
    `---ts=2021-09-04 14:15:42;thread_name=main;id=1;is_daemon=false;priority=5;TCCL=sun.misc.Launcher$AppClassLoader@18b4aac2
        `---[0.0057ms] chapter03.Picture:<init>()
    
    `---ts=2021-09-04 14:15:42;thread_name=main;id=1;is_daemon=false;priority=5;TCCL=sun.misc.Launcher$AppClassLoader@18b4aac2
        `---[0.0131ms] chapter03.Picture:<init>()
    
    `---ts=2021-09-04 14:15:42;thread_name=main;id=1;is_daemon=false;priority=5;TCCL=sun.misc.Launcher$AppClassLoader@18b4aac2
        `---[0.0076ms] chapter03.Picture:<init>()
    
    Command execution times exceed limit: 5, so command will exit. You can set it with -n option.
    
    # stack 输出当前方法被调用的调用路径
    [arthas@16852]$ stack chapter03.Picture <init>
    ts=2021-09-04 14:17:12;thread_name=main;id=1;is_daemon=false;priority=5;TCCL=sun.misc.Launcher$AppClassLoader@18b4aac2
        @chapter03.Picture.<init>()
            at chapter03.OOMTest.main(OOMTest.java:22)
    
    ts=2021-09-04 14:17:12;thread_name=main;id=1;is_daemon=false;priority=5;TCCL=sun.misc.Launcher$AppClassLoader@18b4aac2
        @chapter03.Picture.<init>()
            at chapter03.OOMTest.main(OOMTest.java:22)
    
    # tt 方法执行数据的时空隧道,记录下指定方法每次调用的入参和返回信息,并能对这些不同的时间下调用进行观测
    [arthas@16852]$ tt -t -n 3 chapter03.Picture <init>
    Press Q or Ctrl+C to abort.
    Affect(class count: 1 , method count: 1) cost in 36 ms, listenerId: 10
    INDEX       TIMESTAMP                    COST(ms)      IS-RET      IS-EXP     OBJECT                CLASS                                       METHOD
    -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
    1000        2021-09-04 14:20:24          0.1697        true        false      0x7506e922            Picture                                     <init>
    1001        2021-09-04 14:20:24          0.0126        true        false      0x573fd745            Picture                                     <init>
    1002        2021-09-04 14:20:24          0.02          true        false      0x15327b79            Picture                                     <init>
    Command execution times exceed limit: 3, so command will exit. You can set it with -n option.