cgroup-scripts

Set of scripts to get cgroup limits information within containers.

Examples

All scripts will print the requested information to stdout. Any unexpected behavior will be printed to stderr.

If the VERBOSE environment variable is set to true, the scripts will print additional information to stderr.

Additionally, you can set the DEBUG environment variable to true to print debug information to stderr.

get_cpus.sh

In a system with cgroup v2:

❯ cat get_cpus.sh | docker run --rm -i -e VERBOSE=true alpine sh
VERBOSE(get_cpus.sh): cgroup v2 detected.
VERBOSE(get_cpus.sh): No CPU limits set.
VERBOSE(get_cpus.sh): CPUs:
16

❯ cat get_cpus.sh | docker run --rm -i -e VERBOSE=true --cpus 2 alpine sh
VERBOSE(get_cpus.sh): cgroup v2 detected.
VERBOSE(get_cpus.sh): CPUs:
2

❯ cat get_cpus.sh | docker run --rm -i -e VERBOSE=true --cpus 1.5 alpine sh
VERBOSE(get_cpus.sh): cgroup v2 detected.
VERBOSE(get_cpus.sh): CPUs:
1

❯ cat get_cpus.sh | docker run --rm -i -e VERBOSE=true --cpus 0.5 alpine sh
VERBOSE(get_cpus.sh): cgroup v2 detected.
VERBOSE(get_cpus.sh): CPUs:
1

Another system with cgroup v1:

❯ cat get_cpus.sh | docker run --rm -i -e VERBOSE=true alpine sh
VERBOSE(get_cpus.sh): cgroup v1 detected.
VERBOSE(get_cpus.sh): No CPU limits set.
VERBOSE(get_cpus.sh): CPUs:
8

❯ cat get_cpus.sh | docker run --rm -i -e VERBOSE=true --cpus 2 alpine sh
VERBOSE(get_cpus.sh): cgroup v1 detected.
VERBOSE(get_cpus.sh): CPUs:
2

❯ cat get_cpus.sh | docker run --rm -i -e VERBOSE=true --cpus 1.5 alpine sh
VERBOSE(get_cpus.sh): cgroup v1 detected.
VERBOSE(get_cpus.sh): CPUs:
1

❯ cat get_cpus.sh | docker run --rm -i -e VERBOSE=true --cpus 0.5 alpine sh
VERBOSE(get_cpus.sh): cgroup v1 detected.
VERBOSE(get_cpus.sh): CPUs:
1

get_memory.sh

In a system with cgroup v2:

❯ cat get_memory.sh | docker run --rm -i -e VERBOSE=true alpine sh
VERBOSE(get_memory.sh): cgroup v2 detected.
VERBOSE(get_memory.sh): No memory limits set.
VERBOSE(get_memory.sh): Memory (MB):
15996

❯ cat get_memory.sh | docker run --rm -i -e VERBOSE=true --memory 1g alpine sh
VERBOSE(get_memory.sh): cgroup v2 detected.
VERBOSE(get_memory.sh): Memory (MB):
1024

Another system with cgroup v1:

❯ cat get_memory.sh | docker run --rm -i -e VERBOSE=true alpine sh
VERBOSE(get_memory.sh): cgroup v1 detected.
VERBOSE(get_memory.sh): No memory limits set.
Memory (MB):
32092

❯ cat get_memory.sh | docker run --rm -i -e VERBOSE=true --memory 1g alpine sh
VERBOSE(get_memory.sh): cgroup v1 detected.
VERBOSE(get_memory.sh): Memory (MB):
1024