1) I use next to start a container:
docker run --name test -idt python:3 python -m http.server
2) Then, I try to validate memory usage like next:
a)
root#shubuntu1:~# ps aux | grep "python -m http.server"
root 17416 3.0 0.2 27368 19876 pts/0 Ss+ 17:11 0:00 python -m http.server
b)
root#shubuntu1:~# docker exec -it test ps aux
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 1 0.9 0.2 27368 19876 pts/0 Ss+ 09:11 0:00 python -m http.
c)
root#shubuntu1:~# docker stats --no-stream test
CONTAINER ID NAME CPU % MEM USAGE / LIMIT MEM % NET I/O BLOCK I/O PIDS
d72f2ece6816 test 0.01% 12.45MiB / 7.591GiB 0.16% 3.04kB / 0B 0B / 0B 1
You can see from both docker host & docker container, we could see python -m http.server consume 19876/1024=19.1289MB memory (RSS), but from docker stats, I find 12.45MB, why it show container memory consume even less than the PID1 process in container?
rss RSS resident set size, the non-swapped physical memory that a task has used (in kiloBytes). (alias rssize, rsz).
MEM USAGE / LIMIT the total memory the container is using, and the total amount of memory it is allowed to use
Related
Docker is running in privileged mode.
I want to know if this behavior is expected.
I am running DPDK based application in container.
My server has total 128G memory, I have limited container memory resource to 4G.
which I can see in docker stats.
CONTAINER ID NAME CPU % MEM USAGE / LIMIT MEM % NET I/O BLOCK I/O PIDS [0/18152]
4deda4634b22 my_docker 38.12% 1.455GiB / 4GiB 36.37% 1.53kB / 0B 1.94GB / 755MB 69
I am seeing that even after docker memory is constraint to 4G.
application is able to allocate 32G huge pages memory along with other non huge page memory.
Is it expected?
Does docker run --memory option work only with non-huge page memory?
root#server# docker exec -ti my_docker bash
root#4deda4634b22:/#
root#4deda4634b22:/# ps aux |grep riot
root 893 17.2 0.0 68345740 105260 pts/0 Sl 05:54 1:02 /app/riot <<<<<< application.
root#4deda4634b22:/# cat /proc/meminfo |grep -i huge
AnonHugePages: 909312 kB
ShmemHugePages: 0 kB
**HugePages_Total: 32**
**HugePages_Free: 0**
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 1048576 kB
root#4deda4634b22:/# ls -rlt /mnt/huge/* | wc -l
32
I normally pass the access for huge page and vfio devices via docker run -it --privileged -v /sys/bus/pci/drivers:/sys/bus/pci/drivers -v /sys/kernel/mm/hugepages:/sys/kernel/mm/hugepages -v /sys/devices/system/node:/sys/devices/system/node -v /dev:/dev.
It looks like you are missing the same.
I have run free -h and see that I have 29G of swap space.
total used free shared buff/cache available
Mem: 15G 6.9G 8.8G 17M 223M 8.9G
Swap: 29G 2.0M 29G
I have also enabled 100 swappiness.
$ sudo sysctl vm.swappiness=100
vm.swappiness = 100
$ cat /proc/sys/vm/swappiness
100
However, docker build --memory-swap=20g does not appear to use the swap space. This is the output of htop throughout the docker build.
1 [|||||||||||||||| 18.7%]
2 [||||||| 7.3%]
3 [|||||||||||||||||||||| 26.5%]
4 [||||||||||||||| 18.0%]
Mem[||||||||||||||||||||||||||||||||||| 6.47G/15.9G]
Swp[| 2.00M/29.6G]
This is the docker build command:
docker build --build-arg NODE_OPTIONS="--max-old-space-size=325" \
--memory=600m --memory-swap=20g \
--cpu-period=100000 --cpu-quota=50000 \
--no-cache --tag farm_app_image:latest --file Dockerfile .
The docker build appears to be running out of RAM, because the build's internal process (NodeJS) runs out of heap space and crashes. Also, immediately before the crash the memory is maxed:
shaun#DESKTOP-5T629JB:/mnt/c/Users/bigfo$ docker ps -q | xargs docker stats --no-stream
CONTAINER ID NAME CPU % MEM USAGE / LIMIT MEM % NET I/O BLOCK I/O PIDS
66bdf8efb492 charming_maxwell 51.72% 562.2MiB / 600MiB 93.70% 46.8MB / 1.53MB 277MB / 230MB 94
Why is it running out of RAM without using the swap space? How can we make it use the available swap space?
May be you should try to run it with --privileged flag.
docker run -ti --privileged yourimage
But make sure that you know what you are doing.
You should also read docker-tips-privilaged-flag
I want to deploy 100 containers to one of my linux pc.
If not use docker, the memory is ok for that 100 services.
But if use docker, I see next:
25504 0.0 0.0 10796 5060 ? Sl 12:41 0:00 containerd-shim -namespace moby -workdir /var/lib/containerd/io.containerd.runtime.v1.linux/moby/779ab7bff4bed93d2912437e58e9b830c2f72ef2d8f3b4a5ba31e6d0db8e72b2 -address /run/containerd/containerd.sock -containerd-binary /usr/bin/containerd -runtime-root /var/run/docker/runtime-runc
That means for one container, containerd-shim will cost 5M memory, the worse thing is: for every new container there will be one containerd-shim process. This means for 100 containers, there will be additional 5M * 100 = 500M memory consume.
Is above expected? Any chance for me to try to reduce the 500M?
steps to use runc
-Extract json from Docker image:
mkdir my_container
cd my_container
mkdir rootfs
docker export $(docker create busybox) | tar -C rootfs -xvf -
docker-runc spec
-start the container
runc run container-name
Source
PS : you may also try to add the run time to Docker daemon:
docker daemon --add-runtime "oci=/usr/local/sbin/runc"
CONTAINER CPU % MEM USAGE / LIMIT MEM % NET I/O BLOCK I/O PIDS
48c16e180af6 0.20% 91.48MiB / 31.31GiB 0.29% 3.86kB / 0B 85.3MB / 0B 33
f734efe5a249 0.00% 472KiB / 31.31GiB 0.00% 3.97kB / 0B 12.3kB / 0B 1
165a7b031093 0.00% 480KiB / 31.31GiB 0.00% 9.49kB / 0B 3.66MB / 0B 1
Does anyone know how to get resource consumption of a specific Docker container within its running environment?
Outside of a container, we can get it easily by typing a command "docker stats". Besides, if I try to get resource consumption inside a container, it will get the consumption (RAM, CPU) of the physical computer which the container runs on.
Another option is using 'htop' command, but it does not show the result exactly compared to 'docker stats' command.
If you want the processes consumption inside the container, you can go into the container and monitor the processes.
docker exec -it <container-name> watch ps -aux
Notice that after running the above command, the container doesn't know about any docker processes running.
Docker Version :17.04.0-ce
os :windows 7
I start container using the command :docker run -it -memory 4096MB <container-id>
check the memory using the command :docker stats --no-stream | grep <container-id>
the result is :
5fbc6df8f90f 0.23% 86.52 MB / 995.8 Mib 2.59% 648B / 0B 17.2G / 608 MB 31
when update the memory,the result is also the same:
$ docker update -m 4500MB --memory-swap 4500MB --memory-reservation 4500MB 5fbc6df8f90f
5fbc6df8f90f
$ docker stats --no-stream | grep 5fbc6df8f90f
5fbc6df8f90f 0.23% 86.52 MB / 995.8 Mib 2.59% 648B / 0B 17.2G / 608 MB 31
why "--memory" can not work ,the memory is always the same 995.8Mib?
The docker stats command is showing you how much memory the entire docker host has, or with D4W, how much memory you have in the Linux VM. To increase this threshold, go into the settings of Docker to change the memory allocated to the VM. See this documentation for more details.