社交网站开发难度,刷粉网站开发,广州网站开发设计,网站地图优化定位线上最耗CPU的线程
准备工作
启动一个程序。 arthas-demo是一个简单的程序#xff0c;每隔一秒生成一个随机数#xff0c;再执行质因数分解#xff0c;并打印出分解结果。
curl -O https://alibaba.github.io/arthas/arthas-demo.jar
java -jar arthas-demo.jar[root…定位线上最耗CPU的线程
准备工作
启动一个程序。 arthas-demo是一个简单的程序每隔一秒生成一个随机数再执行质因数分解并打印出分解结果。
curl -O https://alibaba.github.io/arthas/arthas-demo.jar
java -jar arthas-demo.jar[rootlocalhost ~]# curl -O https://alibaba.github.io/arthas/arthas-demo.jar% Total % Received % Xferd Average Speed Time Time Time CurrentDload Upload Total Spent Left Speed
100 3743 100 3743 0 0 3022 0 0:00:01 0:00:01 --:--:-- 3023
[rootlocalhost ~]# java -jar arthas-demo.jar
18137*7*37
illegalArgumentCount: 1, number is: -180005, need 2
illegalArgumentCount: 2, number is: -111175, need 2
185055*3701
1666917*23813
10578711*59*163
601482*2*11*1367
1969833*3*43*509
illegalArgumentCount: 3, number is: -173479, need 2
illegalArgumentCount: 4, number is: -112840, need 2
395022*19751
....
传统方式
通过top命令找到最耗时的进程
[rootlocalhost ~]# top
top - 11:11:05 up 20:02, 3 users, load average: 0.09, 0.07, 0.05
Tasks: 225 total, 1 running, 224 sleeping, 0 stopped, 0 zombie
%Cpu(s): 0.0 us, 0.7 sy, 0.0 ni, 99.3 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
KiB Mem : 1421760 total, 135868 free, 758508 used, 527384 buff/cache
KiB Swap: 2097148 total, 2070640 free, 26508 used. 475852 avail Mem
Change delay from 3.0 toPID USER PR NI VIRT RES SHR S %CPU %MEM TIME COMMAND98344 root 20 0 2422552 23508 12108 S 0.7 1.7 0:00.32 java1 root 20 0 194100 6244 3184 S 0.0 0.4 0:20.41 systemd2 root 20 0 0 0 0 S 0.0 0.0 0:00.12 kthreadd4 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kworker/0:0H6 root 20 0 0 0 0 S 0.0 0.0 0:20.25 ksoftirqd/0
找到进程号是98344。
找到进程中最耗CUP的线程
使用ps -Lp #pid cu命令查看某个进程中的线程CPU消耗排序
[rootlocalhost ~]# ps -Lp 98344 cu
USER PID LWP %CPU NLWP %MEM VSZ RSS TTY STAT START TIME COMMAND
root 98344 98344 0.0 10 4.1 2422552 59060 pts/0 Sl 11:09 0:00 java
root 98344 98345 0.0 10 4.1 2422552 59060 pts/0 Sl 11:09 0:04 java
root 98344 98346 0.0 10 4.1 2422552 59060 pts/0 Sl 11:09 0:01 VM Thread
root 98344 98347 0.0 10 4.1 2422552 59060 pts/0 Sl 11:09 0:00 Reference Handl
root 98344 98348 0.0 10 4.1 2422552 59060 pts/0 Sl 11:09 0:00 Finalizer
root 98344 98349 0.0 10 4.1 2422552 59060 pts/0 Sl 11:09 0:00 Signal Dispatch
root 98344 98350 0.0 10 4.1 2422552 59060 pts/0 Sl 11:09 0:05 C2 CompilerThre
root 98344 98351 0.0 10 4.1 2422552 59060 pts/0 Sl 11:09 0:00 C1 CompilerThre
root 98344 98352 0.0 10 4.1 2422552 59060 pts/0 Sl 11:09 0:00 Service Thread
root 98344 98353 0.1 10 4.1 2422552 59060 pts/0 Sl 11:09 0:19 VM Periodic Tas看TIME列可以看出那个线程耗费CUP多根据LWP列可以看到线程的ID号但是需要转换成16进制才可以查询线程堆栈信息。
获取线程id的十六进制码
使用printf %x\n 98345命令做进制转换
[rootlocalhost ~]# printf %x\n 98345
18029查看线程堆栈信息
使用jstack获取堆栈信息jstack 98344 | grep -A 10 18029
[rootlocalhost ~]# jstack 98344 | grep -A 10 18029
main #1 prio5 os_prio0 tid0x00007fb88404b800 nid0x18029 waiting on condition [0x00007fb88caab000]java.lang.Thread.State: TIMED_WAITING (sleeping)at java.lang.Thread.sleep(Native Method)at java.lang.Thread.sleep(Thread.java:340)at java.util.concurrent.TimeUnit.sleep(TimeUnit.java:386)at demo.MathGame.main(MathGame.java:17)VM Thread os_prio0 tid0x00007fb8840f2800 nid0x1802a runnableVM Periodic Task Thread os_prio0 tid0x00007fb884154000 nid0x18031 waiting on condition通过命令我们可以看到这个线程的对应的耗时代码是在demo.MathGame.main(MathGame.java:17)
grep -C 5 foo file 显示file文件里匹配foo字串那行以及上下5行
grep -B 5 foo file 显示foo及前5行
grep -A 5 foo file 显示foo及后5行使用Arthas
可以直接使用dashboardthread命令进行定位。只是我们线上可能大部分情况下不允许装arthas。
启动Arthas
(base) adminwangyuhao Desktop % java -jar arthas-demo.jar
Error: Unable to access jarfile arthas-demo.jar
(base) adminwangyuhao Desktop % java -jar arthas-boot.jar
[INFO] JAVA_HOME: /Library/Java/JavaVirtualMachines/jdk1.8.0_281.jdk/Contents/Home/jre
[INFO] arthas-boot version: 3.7.2
[INFO] Found existing java process, please choose one and input the serial number of the process, eg : 1. Then hit ENTER.
* [1]: 16897 arthas-demo.jar[2]: 407
1
[INFO] local lastest version: 3.6.7, remote lastest version: 3.7.2, try to download from remote.
[INFO] Start download arthas from remote server: https://arthas.aliyun.com/download/3.7.2?mirroraliyun
[INFO] File size: 17.84 MB, downloaded size: 6.05 MB, downloading ...
[INFO] File size: 17.84 MB, downloaded size: 10.81 MB, downloading ...
[INFO] File size: 17.84 MB, downloaded size: 14.74 MB, downloading ...
[INFO] Download arthas success.
[INFO] arthas home: /Users/admin/.arthas/lib/3.7.2/arthas
[INFO] Try to attach process 16897
Picked up JAVA_TOOL_OPTIONS:
[INFO] Attach process 16897 success.
[INFO] arthas-client connect 127.0.0.1 3658,---. ,------. ,--------.,--. ,--. ,---. ,---. / O \ | .--. --. .--| -- | / O \ .-
| .-. || --. | | | .--. || .-. |. -.
| | | || |\ \ | | | | | || | | |.- |
-- ---- -- -- -- ---- ------- wiki https://arthas.aliyun.com/doc
tutorials https://arthas.aliyun.com/doc/arthas-tutorials.html
version 3.7.2
main_class demo.MathGame
pid 16897
time 2024-03-19 08:59:26 通过dashboard查看实时数据面板
[arthas16897]$ dashboard通过thread查看线程堆栈
[arthas16897]$ thread -n 25
C1 CompilerThread3 [Internal] cpuUsage0.34% deltaTime0ms time588msarthas-command-execute Id22 cpuUsage0.19% deltaTime0ms time15ms RUNNABLEat sun.management.ThreadImpl.dumpThreads0(Native Method)at sun.management.ThreadImpl.getThreadInfo(ThreadImpl.java:448)at com.taobao.arthas.core.command.monitor200.ThreadCommand.processTopBusyThreads(ThreadCommand.java:206)at com.taobao.arthas.core.command.monitor200.ThreadCommand.process(ThreadCommand.java:122)at com.taobao.arthas.core.shell.command.impl.AnnotatedCommandImpl.process(AnnotatedCommandImpl.java:82)at com.taobao.arthas.core.shell.command.impl.AnnotatedCommandImpl.access$100(AnnotatedCommandImpl.java:18)at com.taobao.arthas.core.shell.command.impl.AnnotatedCommandImpl$ProcessHandler.handle(AnnotatedCommandImpl.java:111)at com.taobao.arthas.core.shell.command.impl.AnnotatedCommandImpl$ProcessHandler.handle(AnnotatedCommandImpl.java:108)at com.taobao.arthas.core.shell.system.impl.ProcessImpl$CommandProcessTask.run(ProcessImpl.java:385)at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)at java.util.concurrent.FutureTask.run(FutureTask.java:266)at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)at java.lang.Thread.run(Thread.java:748)VM Periodic Task Thread [Internal] cpuUsage0.07% deltaTime0ms time356msVM Thread [Internal] cpuUsage0.01% deltaTime0ms time46ms
...main Id1 cpuUsage0.0% deltaTime0ms time238ms TIMED_WAITINGat java.lang.Thread.sleep(Native Method)at java.lang.Thread.sleep(Thread.java:340)at java.util.concurrent.TimeUnit.sleep(TimeUnit.java:386)at demo.MathGame.main(MathGame.java:17)C2 CompilerThread2 [Internal] cpuUsage0.0% deltaTime0ms time319msGC task thread#8 (ParallelGC) [Internal] cpuUsage0.0% deltaTime0ms time21msGC task thread#7 (ParallelGC) [Internal] cpuUsage0.0% deltaTime0ms time21msGC task thread#6 (ParallelGC) [Internal] cpuUsage0.0% deltaTime0ms time21ms我们可以找到at demo.MathGame.main(MathGame.java:17)这个堆栈。
通过jad反编译看源码情况
[arthas16897]$ jad demo.MathGameClassLoader:
-sun.misc.Launcher$AppClassLoader5c647e05 -sun.misc.Launcher$ExtClassLoader4554617c Location:
/Users/admin/arthas-demo.jar /** Decompiled with CFR.*/package demo;import java.util.ArrayList;import java.util.List;import java.util.Random;import java.util.concurrent.TimeUnit;public class MathGame {private static Random random new Random();public int illegalArgumentCount 0;public static void main(String[] args) throws InterruptedException {MathGame game new MathGame();while (true) {
/*16*/ game.run();
/*17*/ TimeUnit.SECONDS.sleep(1L);}}public void run() throws InterruptedException {try {
/*23*/ int number random.nextInt() / 10000;
/*24*/ ListInteger primeFactors this.primeFactors(number);
/*25*/ MathGame.print(number, primeFactors);}catch (Exception e) {
/*28*/ System.out.println(String.format(illegalArgumentCount:%3d, , this.illegalArgumentCount) e.getMessage());}}public static void print(int number, ListInteger primeFactors) {StringBuffer sb new StringBuffer(number );
/*34*/ for (int factor : primeFactors) {
/*35*/ sb.append(factor).append(*);}
/*37*/ if (sb.charAt(sb.length() - 1) *) {
/*38*/ sb.deleteCharAt(sb.length() - 1);}
/*40*/ System.out.println(sb);}public ListInteger primeFactors(int number) {
/*44*/ if (number 2) {
/*45*/ this.illegalArgumentCount;throw new IllegalArgumentException(number is: number , need 2);}ArrayListInteger result new ArrayListInteger();
/*50*/ int i 2;
/*51*/ while (i number) {
/*52*/ if (number % i 0) {
/*53*/ result.add(i);
/*54*/ number / i;
/*55*/ i 2;continue;}
/*57*/ i;}
/*61*/ return result;}}Affect(row-cnt:1) cost in 491 ms.
[arthas16897]$ 参考
https://arthas.aliyun.com/doc/commands.html#jvm-%E7%9B%B8%E5%85%B3
