CODEWITHSUNDEEP
dockerdocker-engine
user363778
user363778

Reputation:

Set the number of CPU cores of a container using Docker Engine API

I have a backend server program that launches docker containers using the Docker Engine API (Json API) and I would like to limit the number of CPU cores per docker container to e.g. 1.

The Docker Engine API documentation has several options to configure the CPU settings of a container, see https://docs.docker.com/engine/api/v1.24:

"HostConfig": {
     "CpuPercent": 80,
     "CpuShares": 512,
     "CpuPeriod": 100000,
     "CpuQuota": 50000,
     "CpusetCpus": "0,1",
     "CpusetMems": "0,1"
}

I could use CpusetCpus for this but this is quite cumbersome as I need to keep a list of which docker containers are assigned to which CPU cores. (I don't care on which CPU core my container runs, I just want to avoid that it uses more than 1 CPU core.)

I could also set the CpuQuota so that each docker container uses only e.g. 12.5% of all CPU cores, which corresponds to 1 CPU core on a server with 8 CPU cores. The problem with this approach is that if I run my backend program on a different server with a different number of CPU cores the CpuQuota setting of 12.5% does not correspond to 1 CPU core anymore.

Both options above are cumbersome and far from ideal. There must be a better/simpler way to set the number of CPU cores per container?!

Upvotes: 3

Views: 1812

Answers (1)

King Chung Huang
King Chung Huang

Reputation: 5624

You can set NanoCPUs. 1000000000 units would equal 1 core.

Upvotes: 7

Related Questions