JVM相关查询

jps 查看运行中的java进程及其启动类名和参数, JVM参数

jps -lmv

输出

24929 sun.tools.jps.Jps -lmv -Dapplication.home=/home/es/software/jdk1.8.0_181 -Xms8m
19092 ager.jar -Xms16G -Xmx16G -XX:MetaspaceSize=256m -XX:+HeapDumpOnOutOfMemoryError -Dspring.profiles.active=dev -Duser.timezone=GMT+8
15785 arthas-boot.jar
6105 org.neo4j.server.CommunityEntryPoint --home-dir=/opt/neo4j-community --config-dir=/opt/neo4j-community/conf -Xms10485760k -Xmx10485760k -XX:+UseG1GC -XX:-OmitStackTraceInFastThrow -XX:+AlwaysPreTouch -XX:+UnlockExperimentalVMOptions -XX:+TrustFinalNonStaticFields -XX:+DisableExplicitGC -XX:MaxInlineLevel=15 -XX:-UseBiasedLocking -Djdk.nio.maxCachedBufferSize=262144 -Dio.netty.tryReflectionSetAccessible=true -Djdk.tls.ephemeralDHKeySize=2048 -Djdk.tls.rejectClientInitiatedRenegotiation=true -XX:FlightRecorderOptions=stackdepth=256 -XX:+UnlockDiagnosticVMOptions -XX:+DebugNonSafepoints -Dlog4j2.disable.jmx=true -Dfile.encoding=UTF-8

jstat 查看GC情况

# 每隔1000毫秒, 打印 19092 这个进程的jvm的gc情况
jstat -gcutil 19092 1000

输出

  S0     S1     E      O      M     CCS    YGC     YGCT    FGC    FGCT     GCT   
  0.00 100.00  79.79   8.90  95.06  85.38     31    2.333     0    0.000    2.333
  0.00 100.00  79.79   8.90  95.06  85.38     31    2.333     0    0.000    2.333
  0.00 100.00  79.79   8.90  95.06  85.38     31    2.333     0    0.000    2.333

jstack 查看jvm中, 各个线程的堆栈情况, 当一个线程长时间未返回时, 可以通过这个命令查看卡在哪里

# 查看 19092 这个进程下, java各线程的堆栈
jstack -l 19092

输出

"TDO-thread-17" #6669 prio=5 os_prio=0 cpu=4.90ms elapsed=63147.14s tid=0x00007f7e88034000 nid=0x4446 waiting on condition  [0x00007f7e76ceb000]
   java.lang.Thread.State: WAITING (parking)
	at jdk.internal.misc.Unsafe.park(java.base@11/Native Method)
	- parking to wait for  <0x0000000402abefa0> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
	at java.util.concurrent.locks.LockSupport.park(java.base@11/LockSupport.java:194)
	at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(java.base@11/AbstractQueuedSynchronizer.java:2081)
	at java.util.concurrent.LinkedBlockingQueue.take(java.base@11/LinkedBlockingQueue.java:433)
	at java.util.concurrent.ThreadPoolExecutor.getTask(java.base@11/ThreadPoolExecutor.java:1054)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(java.base@11/ThreadPoolExecutor.java:1114)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(java.base@11/ThreadPoolExecutor.java:628)
	at java.lang.Thread.run(java.base@11/Thread.java:834)

   Locked ownable synchronizers:
	- None

"TDO-thread-18" #6670 prio=5 os_prio=0 cpu=0.87ms elapsed=63089.62s tid=0x00007f7e0403f800 nid=0x461e waiting on condition  [0x00007f7e75edd000]
   java.lang.Thread.State: WAITING (parking)
	at jdk.internal.misc.Unsafe.park(java.base@11/Native Method)
	- parking to wait for  <0x0000000402abefa0> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
	at java.util.concurrent.locks.LockSupport.park(java.base@11/LockSupport.java:194)
	at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(java.base@11/AbstractQueuedSynchronizer.java:2081)
	at java.util.concurrent.LinkedBlockingQueue.take(java.base@11/LinkedBlockingQueue.java:433)
	at java.util.concurrent.ThreadPoolExecutor.getTask(java.base@11/ThreadPoolExecutor.java:1054)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(java.base@11/ThreadPoolExecutor.java:1114)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(java.base@11/ThreadPoolExecutor.java:628)
	at java.lang.Thread.run(java.base@11/Thread.java:834)

   Locked ownable synchronizers:
	- None

基础环境查询

综合

# top
top
# 运行时间, 负载
uptime
# virtual memory statistics
vmstat 

CPU 相关

# 查看CPU个数
grep "processor" /proc/cpuinfo| wc -l
# 查看所有CPU的负载情况
mpstat

输出

7.x86_64 (anyhost) 	07/29/2022 	_x86_64(40 CPU)

10:16:56 AM  CPU    %usr   %nice    %sys %iowait    %irq   %soft  %steal  %guest  %gnice   %idle
10:16:56 AM  all    1.24    0.00    0.17    0.07    0.00    0.00    0.00    0.00    0.00   98.53

内存相关

free -h

输出

              total        used        free      shared  buff/cache   available
Mem:            62G         37G        9.6G         12G         15G         12G
Swap:            0B          0B          0B

磁盘相关, 查看磁盘情况

df -h
du / -d1 -h

磁盘IO情况

iostat -h

输出

Linux 3.10.0-327.el7.x86_64 (anyhost) 	07/29/2022 	_x86_64(40 CPU)

avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           1.24    0.00    0.17    0.07    0.00   98.53

Device:            tps    kB_read/s    kB_wrtn/s    kB_read    kB_wrtn
sda                37.37        73.32       799.55  571577817 6233264651
dm-0               29.89        70.40       460.19  548840983 3587664105
dm-1               28.53         0.17       113.95    1303200  888320856
dm-2               32.86         0.14       131.28    1109529 1023466028
dm-3               11.15         2.60        94.13   20292242  733811333

进程和线程

统计各进程及其线程数量, 看程序名和PID

pstree
# 查看各进程及其下面的线程
pstree -p
# 查看指定的进程及其下面的线程
pstree -p pid

查看具体进程, 这样能看到进程的执行参数

ps aux|grep java