beld beldpro-ci

	# try to run more than the amount of PIDs that are allowed
	# - we should see `fork()` syscall erroring:
	docker run --pids-limit 100 cirocosta/stress pid -n 300

	Starting to spawn 300 blocking children
	Error:

	Fork returned -1.

	File: src/pid.c

	docker run -d --name nginx --pids-limit 100 nginx:alpine
	d9bd65d2e98ec...

	find /sys/fs/cgroup/ -name "d9bd65d2e98*"
	/sys/fs/cgroup/cpu,cpuacct/docker/d9bd65d2e...
	/sys/fs/cgroup/cpuset/docker/d9bd65d2e98ec4...
	/sys/fs/cgroup/devices/docker/d9bd65d2e98ec...
	/sys/fs/cgroup/pids/docker/d9bd65d2e98ec418...
	/sys/fs/cgroup/freezer/docker/d9bd65d2e98ec...
	/sys/fs/cgroup/perf_event/docker/d9bd65d2e9...

	# let's get the ID of the container. Docker uses that ID
	# to name things in the host to we can probably use it to
	# find the cgroup created for the container
	# under the parent docker cgroup
	docker ps
	CONTAINER ID IMAGE COMMAND
	a730051832e7 cirocosta/stress "pid -n 300"

	# Having the prefix in hands, let's search for it under the
	# mountpoint for cgroups in our system

	# Run a container that will spawn 300 processes.
	docker run cirocosta/stress pid -n 300
	Starting to spawn 300 blocking children
	[1] Waiting for SIGINT

	# Open another window and see that we have 300
	# PIDS
	docker stats
	CONTAINER … MEM USAGE / LIMIT PIDS
	a730051832 … 21.02MiB / 1.951GiB 300

	docker-runc exec -t ece80(...)bc19 sh
	/mnt
	└── cloudstor
	└── max
	└── my-volume-1 # the volume I created!
	└── my-file

	docker plugin inspect <plugin-id>
	...
	"PidHost": false,
	"PropagatedMount": "/mnt", # this is interesting
	"User": {},
	...

	# docker plugin ls --no-trunc
	ID NAME DESCR...
	ece80624f9b17(...) cloudstor:aws cloud...


	cat /run/docker/libcontainerd/ece806249b1(...)/config.json \| jq

	{
	"ociVersion": "1.0.0-rc2-dev",
	"platform": {

	docker run \
	--rm \ # remove the container after we run it
	-it \ # add a tty and start it w/ interactive mode
	--privileged \ # grant all permissions to the container
	--pid=host \ # share the host PID space
	justincormack/nsenter1 \ # magic 🎩
	/bin/sh # start /bin/sh

	docker4x/shell-aws:17.05.0-ce-aws2 0.0.0.0:22->22/tcp shell-aws
	docker4x/l4controller-aws:17.05.0-ce-aws2 l4controller-aws
	docker4x/meta-aws:17.05.0-ce-aws2 <internal-ip>:9024->8080/tcp meta-aws
	docker4x/guide-aws:17.05.0-ce-aws2 guide-aws