moby/libnetwork#1113 repro

repro.sh

#!/bin/bash
 
sudo docker pull registry:2
 
cd /proc/$(pidof docker)/task
if [ "$?" -ne 0 ]; then
    echo >&2 "/proc/$(pidof docker)/task doesn't exist or isn't a directory."
    exit 1
fi
 
# Run a loop 100 times.
# Each iteration of the loop will start
# ten containers in parallel, then stop them in parallel.
# After the containers have stopped, check that all of
# the docker daemon's threads are in the same namespace.
# This is essentially the same repro as
# https://github.com/docker/libnetwork/issues/1113
# but with many more tries, since the bug is non-deterministic
i=1
 
while [ "${i}" -le "100" ]; do
    seq 10 | xargs -I{} -P10 sudo docker run -d registry:2
    if [ "$?" -ne 0 ]; then
        echo >&2 "Failed to start all containers"
        exit 1
    fi
 
    sudo docker ps -q | xargs sudo docker stop
    if [ "$?" -ne 0 ]; then
        echo >&2 "Failed to stop all container"
        exit 1
    fi
 
    namespacecount=$(sudo ls -l */ns/net \
    | awk '{print $NF}' \
    | sort -u \
    | wc -l)
    [ "${namespacecount}" -eq "1" ]
    if [ "$?" -ne 0 ]; then
        echo >&2 "FATAL: Daemons threads found using ${namespacecount} different namespaces"
        exit 1
    fi
 
    let i++
done
 
echo "All daemon threads used the same namespace"