Java项目上线后，CPU过高如何定位原因

top

top - 08:37:41 up 2 days, 23:34,  6 users,  load average: 5.17, 5.48, 5.61
Tasks: 16603 total,   1 running, 16600 sleeping,   0 stopped,   2 zombie
%Cpu(s):  5.1 us,  0.9 sy,  0.0 ni, 94.1 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st
KiB Mem : 52807283+total, 25800396+free, 22069265+used, 49376204 buff/cache
KiB Swap: 13421772+total, 13421772+free,        0 used. 30150979+avail Mem 

   PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND                                                                                                                                         
 96442 root      20   0  208.2g   4.9g  43880 S 600.3  1.0  15290:04 java                                                                                                                                            
 96302 root      20   0  161.0g   4.1g  43776 S 100.3  0.8   4165:50 java

top -H -p 进程PID

top -H -p 96442

top - 08:39:39 up 2 days, 23:36,  6 users,  load average: 5.95, 5.68, 5.66
Threads: 10892 total,   6 running, 10886 sleeping,   0 stopped,   0 zombie
%Cpu(s):  5.0 us,  0.6 sy,  0.0 ni, 94.3 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st
KiB Mem : 52807283+total, 25800400+free, 22068240+used, 49386436 buff/cache
KiB Swap: 13421772+total, 13421772+free,        0 used. 30152022+avail Mem 

   PID USER      PR  NI    VIRT    RES    SHR S %CPU %MEM     TIME+ COMMAND                                                                                                                                          
110854 root      20   0  208.2g   4.9g  43880 R 99.9  1.0   2381:35 java                                                                                                                                             
113715 root      20   0  208.2g   4.9g  43880 R 99.9  1.0   2289:06 java                                                                                                                                             
 74564 root      20   0  208.2g   4.9g  43880 R 99.9  1.0   2224:58 java                                                                                                                                             
  3097 root      20   0  208.2g   4.9g  43880 R 99.9  1.0   2233:56 java                                                                                                                                             
 14728 root      20   0  208.2g   4.9g  43880 R 99.9  1.0   2353:03 java                                                                                                                                             
123444 root      20   0  208.2g   4.9g  43880 R 99.4  1.0   2287:02 java   

printf '0x%x\n' 线程PID


[root@localhost tigersharks]# printf '0x%x\n' 74564
0x12344

jstack 进程PID |grep 16进制线程PID -A 20

jstack 96442 |grep 0x12344 -A 20


root@localhost bin]# ./jstack 40361 |grep 0xb1cd -A 20
"pool-3-thread-1" #204 prio=5 os_prio=0 tid=0x00007fd2e0002000 nid=0xb1cd runnable [0x00007fd3389e8000]
   java.lang.Thread.State: RUNNABLE
        at java.io.UnixFileSystem.list(Native Method)
        at java.io.File.list(File.java:1122)
        at java.io.File.listFiles(File.java:1207)
        at clamAv.fileScan.ScanMonitor.lambda$startMonitor$1(ScanMonitor.java:275)
        at clamAv.fileScan.ScanMonitor$$Lambda$1187/2062054922.run(Unknown Source)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
        at java.lang.Thread.run(Thread.java:748)