一、简介

stress 可以对linux机器做压力测试，是一个比较好用的命令

二、创建一个ubuntu image

[root@iZ2vceej7yes1abpm7yec2Z ~]# docker run -it ubuntu
Unable to find image 'ubuntu:latest' locally
latest: Pulling from library/ubuntu
6a5697faee43: Pull complete 
ba13d3bc422b: Pull complete 
a254829d9e55: Pull complete 
Digest: sha256:fff16eea1a8ae92867721d90c59a75652ea66d29c05294e6e2f898704bdb8cf1
Status: Downloaded newer image for ubuntu:latest
[root@iZ2vceej7yes1abpm7yec2Z ~]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
ubuntu              latest              d70eaf7277ea        2 weeks ago         72.9MB

三、在容器中安装stress

由于pull下来的ubuntu是一个基础班，非常的干净，连vim都没有，所以先更换源：

root@76c25bdb1008:/# echo "deb http://mirrors.aliyun.com/ubuntu/ xenial main restricted universe multiverse" >/etc/apt/sources.list
root@76c25bdb1008:/# 
root@76c25bdb1008:/# more etc/apt/sources.list
deb http://mirrors.aliyun.com/ubuntu/ xenial main restricted universe multiverse
root@76c25bdb1008:/# 
root@76c25bdb1008:/# echo "deb http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted universe multiverse" >> /etc/apt/sources.list
root@76c25bdb1008:/# 
root@76c25bdb1008:/# echo "deb http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted universe multiverse" >> /etc/apt/sources.list
root@76c25bdb1008:/# 
root@76c25bdb1008:/# echo "deb http://mirrors.aliyun.com/ubuntu/ xenial-proposed main restricted universe multiverse" >> /etc/apt/sources.list
root@76c25bdb1008:/# 
root@76c25bdb1008:/# echo "deb http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse" >> /etc/apt/sources.list
root@76c25bdb1008:/# 
root@76c25bdb1008:/# echo "deb-src http://mirrors.aliyun.com/ubuntu/ xenial main restricted universe multiverse" >> /etc/apt/sources.list
root@76c25bdb1008:/# 
root@76c25bdb1008:/# echo "deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted universe multiverse" >> /etc/apt/sources.list
root@76c25bdb1008:/# 
root@76c25bdb1008:/# echo "deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted universe multiverse" >> /etc/apt/sources.list
root@76c25bdb1008:/# 
root@76c25bdb1008:/# echo "deb-src http://mirrors.aliyun.com/ubuntu/ xenial-proposed main restricted universe multiverse" >> /etc/apt/sources.list
root@76c25bdb1008:/# 
root@76c25bdb1008:/# echo "deb-src http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse" >> /etc/apt/sources.list

apt-get update && apt-get install -y stress

root@76c25bdb1008:/# apt update
Get:1 http://mirrors.aliyun.com/ubuntu xenial InRelease [247 kB]
Get:2 http://mirrors.aliyun.com/ubuntu xenial-security InRelease [109 kB]
Get:3 http://mirrors.aliyun.com/ubuntu xenial-updates InRelease [109 kB]
Get:4 http://mirrors.aliyun.com/ubuntu xenial-proposed InRelease [260 kB]
Get:5 http://mirrors.aliyun.com/ubuntu xenial-backports InRelease [107 kB]
Get:6 http://mirrors.aliyun.com/ubuntu xenial/universe Sources [9802 kB]
Get:7 http://mirrors.aliyun.com/ubuntu xenial/restricted Sources [5179 B]
Get:8 http://mirrors.aliyun.com/ubuntu xenial/main Sources [1103 kB]
Get:9 http://mirrors.aliyun.com/ubuntu xenial/multiverse Sources [215 kB]
Get:10 http://mirrors.aliyun.com/ubuntu xenial/multiverse amd64 Packages [176 kB]
Get:11 http://mirrors.aliyun.com/ubuntu xenial/universe amd64 Packages [9827 kB]
Get:12 http://mirrors.aliyun.com/ubuntu xenial/restricted amd64 Packages [14.1 kB]
Get:13 http://mirrors.aliyun.com/ubuntu xenial/main amd64 Packages [1558 kB]
Get:14 http://mirrors.aliyun.com/ubuntu xenial-security/universe Sources [244 kB]
Get:15 http://mirrors.aliyun.com/ubuntu xenial-security/multiverse Sources [4952 B]
Get:16 http://mirrors.aliyun.com/ubuntu xenial-security/main Sources [299 kB]
Get:17 http://mirrors.aliyun.com/ubuntu xenial-security/restricted Sources [3239 B]
Get:18 http://mirrors.aliyun.com/ubuntu xenial-security/main amd64 Packages [1841 kB]
Get:19 http://mirrors.aliyun.com/ubuntu xenial-security/multiverse amd64 Packages [9249 B]
Get:20 http://mirrors.aliyun.com/ubuntu xenial-security/universe amd64 Packages [969 kB]
Get:21 http://mirrors.aliyun.com/ubuntu xenial-security/restricted amd64 Packages [15.9 kB]
Get:22 http://mirrors.aliyun.com/ubuntu xenial-updates/universe Sources [533 kB]
Get:23 http://mirrors.aliyun.com/ubuntu xenial-updates/restricted Sources [3941 B]
Get:24 http://mirrors.aliyun.com/ubuntu xenial-updates/multiverse Sources [13.5 kB]
Get:25 http://mirrors.aliyun.com/ubuntu xenial-updates/main Sources [655 kB]
Get:26 http://mirrors.aliyun.com/ubuntu xenial-updates/universe amd64 Packages [1513 kB]
Get:27 http://mirrors.aliyun.com/ubuntu xenial-updates/main amd64 Packages [2353 kB]
Get:28 http://mirrors.aliyun.com/ubuntu xenial-updates/restricted amd64 Packages [16.4 kB]
Get:29 http://mirrors.aliyun.com/ubuntu xenial-updates/multiverse amd64 Packages [26.7 kB]
Get:30 http://mirrors.aliyun.com/ubuntu xenial-proposed/main Sources [9460 B]                                                                                                       
Get:31 http://mirrors.aliyun.com/ubuntu xenial-proposed/universe Sources [4365 B]                                                                                                   
Get:32 http://mirrors.aliyun.com/ubuntu xenial-proposed/universe amd64 Packages [18.3 kB]                                                                                           
Get:33 http://mirrors.aliyun.com/ubuntu xenial-proposed/main amd64 Packages [98.5 kB]                                                                                               
Get:34 http://mirrors.aliyun.com/ubuntu xenial-backports/universe Sources [12.3 kB]                                                                                                 
Get:35 http://mirrors.aliyun.com/ubuntu xenial-backports/main Sources [7276 B]                                                                                                      
Get:36 http://mirrors.aliyun.com/ubuntu xenial-backports/universe amd64 Packages [12.6 kB]                                                                                          
Get:37 http://mirrors.aliyun.com/ubuntu xenial-backports/main amd64 Packages [10.9 kB]                                                                                              
Fetched 32.2 MB in 7s (4906 kB/s)                                                                                                                                                   
Reading package lists... Done
Building dependency tree       
Reading state information... Done
All packages are up to date.
root@76c25bdb1008:/# 
root@76c25bdb1008:/# 
root@76c25bdb1008:/# 
root@76c25bdb1008:/# 
root@76c25bdb1008:/# apt-get install -y stress
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following NEW packages will be installed:
  stress
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 16.7 kB of archives.
After this operation, 75.8 kB of additional disk space will be used.
Get:1 http://mirrors.aliyun.com/ubuntu xenial/universe amd64 stress amd64 1.0.4-1 [16.7 kB]
Fetched 16.7 kB in 0s (59.7 kB/s) 
debconf: delaying package configuration, since apt-utils is not installed
Selecting previously unselected package stress.
(Reading database ... 4121 files and directories currently installed.)
Preparing to unpack .../stress_1.0.4-1_amd64.deb ...
Unpacking stress (1.0.4-1) ...
Setting up stress (1.0.4-1) ...
root@76c25bdb1008:/# which stress
/usr/bin/stress
root@76c25bdb1008:/# 

 stress --help

 stress --help
`stress' imposes certain types of compute stress on your system

Usage: stress [OPTION [ARG]] ...
 -?, --help         show this help statement
     --version      show version statement
 -v, --verbose      be verbose
 -q, --quiet        be quiet
 -n, --dry-run      show what would have been done
 -t, --timeout N    timeout after N seconds
     --backoff N    wait factor of N microseconds before work starts
 -c, --cpu N        spawn N workers spinning on sqrt()
 -i, --io N         spawn N workers spinning on sync()
 -m, --vm N         spawn N workers spinning on malloc()/free()
     --vm-bytes B   malloc B bytes per vm worker (default is 256MB)
     --vm-stride B  touch a byte every B bytes (default is 4096)
     --vm-hang N    sleep N secs before free (default none, 0 is inf)
     --vm-keep      redirty memory instead of freeing and reallocating
 -d, --hdd N        spawn N workers spinning on write()/unlink()
     --hdd-bytes B  write B bytes per hdd worker (default is 1GB)

stress --vm 1 --verbose

启动一个worker ，分配256MB 然后释放 ，一直循环往复

:/# stress --vm 1 --verbose
stress: info: [440] dispatching hogs: 0 cpu, 0 io, 1 vm, 0 hdd
stress: dbug: [440] using backoff sleep of 3000us
stress: dbug: [440] --> hogvm worker 1 [441] forked
stress: dbug: [441] allocating 268435456 bytes ...
stress: dbug: [441] touching bytes in strides of 4096 bytes ...
stress: dbug: [441] freed 268435456 bytes
stress: dbug: [441] allocating 268435456 bytes ...
stress: dbug: [441] touching bytes in strides of 4096 bytes ...
stress: dbug: [441] freed 268435456 bytes
stress: dbug: [441] allocating 268435456 bytes ...
stress: dbug: [441] touching bytes in strides of 4096 bytes ...
stress: dbug: [441] freed 268435456 bytes
stress: dbug: [441] allocating 268435456 bytes ...

如果分配的内存超过宿主机内存会发生什么？

/# stress --vm 1 --vm-bytes 50000M --verbose
stress: info: [442] dispatching hogs: 0 cpu, 0 io, 1 vm, 0 hdd
stress: dbug: [442] using backoff sleep of 3000us
stress: dbug: [442] --> hogvm worker 1 [443] forked
stress: dbug: [443] allocating 52428800000 bytes ...
stress: FAIL: [443] (494) hogvm malloc failed: Cannot allocate memory
stress: FAIL: [442] (394) <-- worker 443 returned error 1
stress: WARN: [442] (396) now reaping child worker processes
stress: FAIL: [442] (451) failed run completed in 0s

容器 无法分配。

 四、编写docker file 然后build一个命令行程序

ubuntu-stress]# more Dockerfile 
FROM ubuntu
RUN apt-get update && apt-get install -y stress
ENTRYPOINT ["/usr/bin/stress"]
CMD []

  ubuntu-stress]# docker build -t ninesun0318/ubuntu-stress .

ubuntu-stress]# docker images
REPOSITORY                  TAG                 IMAGE ID            CREATED              SIZE
ninesun0318/ubuntu-stress   latest              675f527c4ed1        About a minute ago   99.7MB
ninesun0318/flask           latest              1f7f63f7ff02        26 hours ago         884MB
python                      3.6                 1297140c6dd2        6 days ago           874MB
ubuntu                      latest              d70eaf7277ea        2 weeks ago          72.9MB
centos                      latest              0d120b6ccaa8        3 months ago         215MB
hello-world                 latest              bf756fb1ae65        10 months ago        13.3kB

通过entrypoint + cmd 是一种流行的运行命令行方式

已一种传参的方式在容器中运行命令

 ubuntu-stress]# docker run -it ninesun0318/ubuntu-stress --vm 1 --verbose
stress: info: [1] dispatching hogs: 0 cpu, 0 io, 1 vm, 0 hdd
stress: dbug: [1] using backoff sleep of 3000us
stress: dbug: [1] --> hogvm worker 1 [5] forked
stress: dbug: [5] allocating 268435456 bytes ...
stress: dbug: [5] touching bytes in strides of 4096 bytes ...
stress: dbug: [5] freed 268435456 bytes
stress: dbug: [5] allocating 268435456 bytes ...
stress: dbug: [5] touching bytes in strides of 4096 bytes ...
stress: dbug: [5] freed 268435456 bytes
stress: dbug: [5] allocating 268435456 bytes ...
stress: dbug: [5] touching bytes in strides of 4096 bytes ...
stress: dbug: [5] freed 268435456 bytes
stress: dbug: [5] allocating 268435456 bytes ...