一个docker host 会运行多个容器，每个容器都需要CPU、内存、IO资源。对于KVM和vmware等虚拟化技术，用户可以控制分配多少CPU、MEM资源给虚拟机。对于容器而言，Docker也提供了类似的机制避免某个容器因占用太多资源而影响其他容器乃至整个host的性能
root@docker-lab:~# docker run -it -m 200M --memory-swap=300M progrium/stress --vm 1 --vm-bytes 280M
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 [7] forked
stress: dbug: [7] allocating 293601280 bytes ...
stress: dbug: [7] touching bytes in strides of 4096 bytes ...
stress: dbug: [7] freed 293601280 bytes
stress: dbug: [7] allocating 293601280 bytes ...
stress: dbug: [7] touching bytes in strides of 4096 bytes ...
stress: dbug: [7] freed 293601280 bytes
stress: dbug: [7] allocating 293601280 bytes ...
stress: dbug: [7] touching bytes in strides of 4096 bytes ...
stress: dbug: [7] freed 293601280 bytes
root@docker-lab:~# docker run -it -m 200M progrium/stress --vm 1 --vm-bytes 410M # 内存不足，自动退出
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 [8] forked
stress: dbug: [8] allocating 429916160 bytes ...
stress: dbug: [8] touching bytes in strides of 4096 bytes ...
stress: FAIL: [1] (416) <-- worker 8 got signal 9
stress: WARN: [1] (418) now reaping child worker processes
stress: FAIL: [1] (422) kill error: No such process
stress: FAIL: [1] (452) failed run completed in 1s
root@docker-lab:~# docker run -it -m 200M progrium/stress --vm 1 --vm-bytes 390M
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 [7] forked
stress: dbug: [7] allocating 408944640 bytes ...
stress: dbug: [7] touching bytes in strides of 4096 bytes ...
stress: dbug: [7] freed 408944640 bytes
stress: dbug: [7] allocating 408944640 bytes ...
stress: dbug: [7] touching bytes in strides of 4096 bytes ...
stress: dbug: [7] freed 408944640 bytes
