top

top - 23:42:01 up 1 day, 14:18,  2 users,  load average: 1.03, 1.01, 1.00
Tasks: 148 total,   1 running, 147 sleeping,   0 stopped,   0 zombie
%Cpu0  :  0.0 us,  0.0 sy,  0.0 ni,100.0 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st
%Cpu1  :  0.3 us,  0.3 sy,  0.0 ni, 99.3 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st
%Cpu2  :  0.3 us,  0.0 sy,  0.0 ni, 99.7 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st
%Cpu3  :  0.0 us,  0.0 sy,  0.0 ni,100.0 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st
MiB Mem :   7459.9 total,    594.0 free,   1205.1 used,   5968.6 buff/cache
MiB Swap:      0.0 total,      0.0 free,      0.0 used.   6254.8 avail Mem
  scroll coordinates: y = 1/148 (tasks), x = 1/12 (fields)
    PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND
   1048 root      20   0 2903416 106608  61980 S   0.0   1.4   2:02.81 dockerd
   1009 root      20   0 1955952  61768  39216 S   0.0   0.8   0:56.45 containerd
    768 daemon    20   0  310472   8308   6448 S   0.0   0.1   0:47.41 rngd
   1046 root      20   0  689948  19568  15476 S   0.0   0.3   0:33.37 aliyun-service.
 114010 www       20   0 1899412 385256  62728 S   0.0   5.0   0:32.70 uvicorn
   2354 www       20   0   68604  32960   7432 S   0.0   0.4   0:31.32 openresty
 113987 root      20   0 2136456  25160  17088 S   0.7   0.3   0:24.66 containerd-shim
  76524 root      20   0 2063044  23976  16748 S   0.0   0.3   0:11.28 containerd-shim
    766 root      20   0  746232  36988  27652 S   0.0   0.5   0:05.96 hbrclient
    769 root      20   0  330836  12488  11424 S   0.0   0.2   0:01.92 rsyslogd
 113726 root      20   0       0      0      0 I   0.0   0.0   0:01.89 kworker/1:1-events_power+
     17 root      20   0       0      0      0 I   0.0   0.0   0:01.37 rcu_preempt
    851 root      20   0  546932  19280  16480 S   0.0   0.3   0:01.32 NetworkManager
    767 root      20   0  713536   4968   3288 S   0.0   0.1   0:01.18 updater
      1 root      20   0   21228  14056  10408 S   0.0   0.2   0:01.11 systemd
 252319 root      20   0       0      0      0 I   0.0   0.0   0:00.97 kworker/0:0-events

• 如何解读 load average
• CPU 分析

注意：

• 搭配 htop

strace

strace = “程序当前在等谁” 偷看程序每一步系统调用

• 卡在网络：在等接口 / RPC / 外部服务

recvfrom(...)
sendto(...)

• 卡在数据库：在等数据库返回

poll(...)
select(...)

• 疯狂读文件：磁盘 IO 压力

read(...)
open(...)

内存泄露、内存溢出和内存逃逸

内存泄露

内存溢出

内存逃逸