rss limiter (bash / linux)

rsslimiter.sh

#!/bin/bash

CGROUP_ROOT="/sys/fs/cgroup"
CGROUP_NAME="rsslimiter"

# CGROUP_CPUSHARES="512"
# CGROUP_BLKIO_THROTTLE_READ_BPS="8:0 $((100*1024*1024)),8:16 $((100*1024*1024))"
CGROUP_MAXMEM="$((32 * 1024 * 1024))"  # in bytes

cgroup_init()
{
	[ -z "${CGROUP_NAME}" ] && return
	CGROUP_BLK_PATH="$CGROUP_ROOT/blkio/$CGROUP_NAME"
	CGROUP_CPU_PATH="$CGROUP_ROOT/cpu/$CGROUP_NAME"
	CGROUP_MEM_PATH="$CGROUP_ROOT/memory/$CGROUP_NAME"
	# We assume /cgroup is already mounted obviously ;)
	# Create cgroup if not already created
	[ -d "$CGROUP_BLK_PATH" ] || mkdir "$CGROUP_BLK_PATH"
	[ -d "$CGROUP_CPU_PATH" ] || mkdir "$CGROUP_CPU_PATH"
	[ -d "$CGROUP_MEM_PATH" ] || mkdir "$CGROUP_MEM_PATH"

	[ ! -f "${CGROUP_BLK_PATH}/tasks" ] && (echo "No cgroup blkio support."; return 1)
	[ ! -f "${CGROUP_CPU_PATH}/tasks" ] && (echo "No cgroup cpu support."; return 1)
	[ ! -f "${CGROUP_MEM_PATH}/tasks" ] && (echo "No cgroup mem support."; return 1)
	
	# Setup limits
	if [ ! -z "$CGROUP_CPU_SHARES" ]; then
		echo $CGROUP_CPU_SHARES > ${CGROUP_CPU_PATH}/cpu.shares
	fi
	if [ ! -z "$CGROUP_BLKIO_THROTTLE_READ_BPS" ]; then
        OIFS="$IFS"; IFS=","; for i in $CGROUP_BLKIO_THROTTLE_READ_BPS; do
			echo $i > ${CGROUP_BLKIO_PATH}/blkio.throttle.read_bps_device
        done; IFS=$OIFS
	fi
	if [ ! -z "$CGROUP_MAXMEM" ]; then
		echo $CGROUP_MAXMEM > ${CGROUP_MEM_PATH}/memory.limit_in_bytes
	fi

	echo $$ > $CGROUP_CPU_PATH/tasks
	echo $$ > $CGROUP_BLK_PATH/tasks
	echo $$ > $CGROUP_MEM_PATH/tasks
	return 0
}

echo "Setting up CGROUP limits..." >&2
cgroup_init
python3 -c 'import time; x=bytearray(1024 * 1024 * 28); time.sleep(5)