Reap zombie processes and perform singal forward in dev container

Signed-off-by: quicksilver <zhifeng.zhang@zilliz.com>

build/docker/env/cpu/ubuntu18.04/Dockerfile

@@ -44,26 +44,18 @@ RUN mkdir -p /usr/local/go && wget -qO- "https://golang.org/dl/go1.15.2.linux-am
     chmod -R 777 "$GOPATH" && chmod -R a+w $(go env GOTOOLDIR)
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
-    openssh-server gdb gdbserver && \
+    gdb gdbserver && \
     apt-get remove --purge -y && \
     rm -rf /var/lib/apt/lists/*
 
-# Taken from - https://docs.docker.com/engine/examples/running_ssh_service/#environment-variables
-RUN mkdir /var/run/sshd && echo 'root:root' | chpasswd && \
-    useradd -u 2000 -ms /bin/bash debugger && echo 'debugger:milvus' | chpasswd
-
-# SSH login fix. Otherwise user is kicked off after login
-RUN sed 's@session\s*required\s*pam_loginuid.so@session optional pam_loginuid.so@g' -i /etc/pam.d/sshd
-
-ENV NOTVISIBLE "in users profile"
-RUN echo "export VISIBLE=now" >> /etc/profile
-
-# 22 for ssh server. 7777 for gdb server.
-EXPOSE 22 7777
+RUN echo 'root:root' | chpasswd
 
 COPY --chown=0:0 build/docker/env/entrypoint.sh /
 
 RUN wget -qO- "https://github.com/benesch/autouseradd/releases/download/1.2.0/autouseradd-1.2.0-amd64.tar.gz" | tar xz -C / --strip-components 1
 
-ENTRYPOINT [ "autouseradd", "--user", "milvus", "--", "/entrypoint.sh" ]
+RUN wget -O /tini https://github.com/krallin/tini/releases/download/v0.19.0/tini && \
+    chmod +x /tini
+
+ENTRYPOINT [ "/tini", "--", "autouseradd", "--user", "milvus", "--", "/entrypoint.sh" ]
 CMD ["tail", "-f", "/dev/null"]

docker-compose.yml

@@ -35,31 +35,6 @@ services:
     networks:
       - milvus
 
-#  gdbserver:
-#    image: ${REPO}:${ARCH}-ubuntu${UBUNTU}-${DATE_VERSION}
-#    build:
-#      context: .
-#      dockerfile: build/docker/env/cpu/ubuntu${UBUNTU}/Dockerfile
-#      cache_from:
-#        - ${REPO}:${ARCH}-ubuntu${UBUNTU}-${LATEST_DATE_VERSION}
-#    security_opt: # options needed for gdb debugging
-#      - seccomp:unconfined
-#      - apparmor:unconfined
-#    environment:
-#      PULSAR_ADDRESS: ${PULSAR_ADDRESS}
-#      ETCD_ADDRESS: ${ETCD_ADDRESS}
-#      MINIO_ADDRESS: ${MINIO_ADDRESS}
-#    volumes:
-#      - .:/go/src/github.com/zilliztech/milvus-distributed:delegated
-#      - ${DOCKER_VOLUME_DIRECTORY:-.docker}/${ARCH}-ubuntu${UBUNTU}-gdbserver-home:/home/debugger:delegated
-#    container_name: debugger
-#    entrypoint: ["/usr/sbin/sshd", "-D"]
-#    ports:
-#      - "7776:22"
-#      - "7777:7777"
-#    networks:
-#      - milvus
-
   etcd:
     image: quay.io/coreos/etcd:v3.4.13
     command: etcd -advertise-client-urls=http://127.0.0.1:2379 -listen-client-urls http://0.0.0.0:2379