Image disk space reduction (#10172) (#10371)

Reduce the disk space taken up during bootup and runtime.

1. Remove python package cache from the base image and from the containers.
2. During bootup, if logs are to be stored in memory, then don't create the `var-log.ext4` file just to delete it later during bootup.
3. For the partition containing `/host`, don't reserve any blocks for just the root user. This just makes sure all disk space is available for all users, if needed during upgrades (for example).

* Remove pip2 and pip3 caches from some containers

Only containers which appeared to have a significant pip cache size are
included here.

Signed-off-by: Saikrishna Arcot <sarcot@microsoft.com>

* Don't create var-log.ext4 if we're storing logs in memory

Signed-off-by: Saikrishna Arcot <sarcot@microsoft.com>

* Run tune2fs on the device containing /host to not reserve any blocks for just the root user

Signed-off-by: Saikrishna Arcot <sarcot@microsoft.com>
(cherry picked from commit 5617b1ae3e)

dockers/docker-base-buster/Dockerfile.j2

@@ -121,7 +121,7 @@ RUN apt-get -y purge   \
 RUN apt-get clean -y                     && \
     apt-get autoclean -y                 && \
     apt-get autoremove -y                && \
-    rm -rf /var/lib/apt/lists/* /tmp/*
+    rm -rf /var/lib/apt/lists/* /tmp/* ~/.cache/
 
 COPY ["etc/rsyslog.conf", "/etc/rsyslog.conf"]
 COPY ["etc/rsyslog.d/*", "/etc/rsyslog.d/"]

dockers/docker-config-engine-buster/Dockerfile.j2

@@ -49,4 +49,4 @@ RUN apt-get purge -y               \
     apt-get clean -y            && \
     apt-get autoclean -y        && \
     apt-get autoremove -y       && \
-    rm -rf /debs /python-wheels
+    rm -rf /debs /python-wheels ~/.cache

dockers/docker-orchagent/Dockerfile.j2

@@ -63,7 +63,7 @@ RUN apt-get purge -y          \
     apt-get clean -y       && \
     apt-get autoclean -y   && \
     apt-get autoremove -y  && \
-    rm -rf /debs
+    rm -rf /debs ~/.cache
 
 COPY ["files/arp_update", "/usr/bin"]
 COPY ["arp_update.conf", "files/arp_update_vars.j2", "/usr/share/sonic/templates/"]

dockers/docker-sonic-mgmt-framework/Dockerfile.j2

@@ -51,6 +51,6 @@ RUN apt-get purge -y python-dev
 
 RUN apt-get remove -y g++ python3-dev
 RUN apt-get clean -y; apt-get autoclean -y; apt-get autoremove -y
-RUN rm -rf /debs
+RUN rm -rf /debs ~/.cache
 
 ENTRYPOINT ["/usr/local/bin/supervisord"]

files/Aboot/boot0.j2

@@ -351,7 +351,12 @@ extract_image() {
     unzip -oq "$swipath" -x boot0 "$dockerfs" -d "$image_path"
 
     ## detect rootfs type
-    rootfs_type=`grep " $target_path " /proc/mounts | cut -d' ' -f3`
+    local mountstr="$(grep " $target_path " /proc/mounts)"
+    local rootdev="$(echo $mountstr | cut -f1 -d' ')"
+    rootfs_type="$(echo $mountstr | cut -d' ' -f3)"
+
+    ## Don't reserve any blocks just for root
+    tune2fs -m 0 -r 0 $rootdev
 
     info "Extracting $dockerfs from swi"
     ## Unpacking dockerfs delayed

files/initramfs-tools/varlog

@@ -11,17 +11,27 @@ case $1 in
     ;;
 esac
 
+logs_inram=false
+
 # Extract kernel parameters
 set -- $(cat /proc/cmdline)
 for x in "$@"; do
     case "$x" in
         varlog_size=*)
             varlog_size="${x#varlog_size=}"
+            ;;
+        logs_inram=on)
+            logs_inram=true
+            ;;
     esac
 done
 
 [ -z "$varlog_size" ] && exit 0
 
+# If logs are being stored in memory, then don't bother
+# creating the log file just to have it deleted afterwards.
+$logs_inram && exit 0
+
 # exit when the var_log.ext4 exists and the size matches
 if [ -e "${rootmnt}/host/disk-img/var-log.ext4" ]; then
     cur_varlog_size=$(ls -l ${rootmnt}/host/disk-img/var-log.ext4 | awk '{print $5}')

installer/arm64/install.sh

@@ -117,6 +117,11 @@ elif [ "$install_env" = "sonic" ]; then
             rm -rf $f
         fi
     done
+
+    demo_dev=$(findmnt -n -o SOURCE --target /host)
+
+    # Don't reserve any blocks just for root
+    tune2fs -m 0 -r 0 $demo_dev
 fi
 
 # Create target directory or clean it up if exists

installer/armhf/install.sh

@@ -117,6 +117,11 @@ elif [ "$install_env" = "sonic" ]; then
             rm -rf $f
         fi
     done
+
+    demo_dev=$(findmnt -n -o SOURCE --target /host)
+
+    # Don't reserve any blocks just for root
+    tune2fs -m 0 -r 0 $demo_dev
 fi
 
 # Create target directory or clean it up if exists

installer/x86_64/install.sh

@@ -434,6 +434,9 @@ if [ "$install_env" = "onie" ]; then
     # Make filesystem
     mkfs.ext4 -L $demo_volume_label $demo_dev
 
+    # Don't reserve any blocks just for root
+    tune2fs -m 0 -r 0 $demo_dev
+
     # Mount demo filesystem
     demo_mnt=$(${onie_bin} mktemp -d) || {
         echo "Error: Unable to create file system mount point"
@@ -466,12 +469,20 @@ elif [ "$install_env" = "sonic" ]; then
             rm -rf $f
         fi
     done
+
+    demo_dev=$(findmnt -n -o SOURCE --target /host)
+
+    # Don't reserve any blocks just for root
+    tune2fs -m 0 -r 0 $demo_dev
 else
     demo_mnt="build_raw_image_mnt"
     demo_dev=$cur_wd/"%%OUTPUT_RAW_IMAGE%%"
 
     mkfs.ext4 -L $demo_volume_label $demo_dev
 
+    # Don't reserve any blocks just for root
+    tune2fs -m 0 -r 0 $demo_dev
+
     echo "Mounting $demo_dev on $demo_mnt..."
     mkdir $demo_mnt
     mount -t auto -o loop $demo_dev $demo_mnt