Allocate same cgroup parent for all containers started by nomad client wrt docker

[hbasappa]

If you have a question, prepend your issue with [question] or preferably use the nomad mailing list.

If filing a bug please include the following:

Nomad version

Output from nomad version 0.8.4

Operating system and Environment details

centos 7

Issue

docker support cgroupParent which can be used to potentassign same cgroupParent to all containers started by nomad client.Nomad does not support it.

https://github.com/hashicorp/nomad/pull/4662 is one way to address this.

Reproduction steps

Nomad Server logs (if appropriate)

Nomad Client logs (if appropriate)

Job file (if appropriate)

[preetapan]

LEaving this issue open, see my comment in https://github.com/hashicorp/nomad/pull/4662. we'll take an updated PR against the docker driver plugin after the ongoing work on that is merged.

[joebeeson]

4844 has been merged

[fredwangwang]

@preetapan is there any plan to add this feature? IMO nomad has the reserved config, but it is not very useful. It only limits how much are reserved from being scheduled but not at all how much can be used post scheduling. Schedule a cpu hog with 10 Mhz CPU allocated (w/o hard limit) can easily take down all system level services (logging, ssh, etc) on the target node.

Assigning all nomad scheduled tasks to a constraint cgroup can be hugely beneficial to prevent nomad hosted job jeopardize the host stability.

[shoenig]

Setting a cgroup parent (as well as reserved.cores) has been possible since Nomad v1.1