Gist by paste.py @ 2014-07-26 01:50:04.495803

lim.sh

#!/bin/bash
# ==============================================================
# CPU limit daemon - set PID's max. percentage CPU consumptions
# ==============================================================

# Variables
CPU_LIMIT=3		# Maximum percentage CPU consumption by each PID
DAEMON_INTERVAL=3	# Daemon check interval in seconds
BLACK_PROCESSES_LIST="sshd"   # Limit only processes defined in this variable. If variable is empty (default) all violating processes are limited.
WHITE_PROCESSES_LIST=   # Limit all processes except processes defined in this variable. If variable is empty (default) all violating processes are limited.

# Check if one of the variables BLACK_PROCESSES_LIST or WHITE_PROCESSES_LIST is defined.
if [[ -n "$BLACK_PROCESSES_LIST" &&  -n "$WHITE_PROCESSES_LIST" ]] ; then    # If both variables are defined then error is produced.
	echo "At least one or both of the variables BLACK_PROCESSES_LIST or WHITE_PROCESSES_LIST must be empty."
	exit 1
elif [[ -n "$BLACK_PROCESSES_LIST" ]] ; then                                 # If this variable is non-empty then set NEW_PIDS_COMMAND variable to bellow command
	NEW_PIDS_COMMAND="top -b -n1 -c | grep -E '$BLACK_PROCESSES_LIST' | gawk '\$9>CPU_LIMIT {print \$1}' CPU_LIMIT=$CPU_LIMIT"
elif [[ -n "$WHITE_PROCESSES_LIST" ]] ; then                                 # If this variable is non-empty then set NEW_PIDS_COMMAND variable to bellow command
	NEW_PIDS_COMMAND="top -b -n1 -c | gawk 'NR>6' | grep -E -v '$WHITE_PROCESSES_LIST' | gawk '\$9>CPU_LIMIT {print \$1}' CPU_LIMIT=$CPU_LIMIT"
else
	NEW_PIDS_COMMAND="top -b -n1 -c | gawk 'NR>6 && \$9>CPU_LIMIT {print \$1}' CPU_LIMIT=$CPU_LIMIT"
fi

# Search and limit violating PIDs
while sleep $DAEMON_INTERVAL
do
	NEW_PIDS=$(eval "$NEW_PIDS_COMMAND")                                                                    # Violating PIDs
	LIMITED_PIDS=$(ps -eo args | gawk '$1=="cpulimit" {print $3}')                                          # Already limited PIDs
	QUEUE_PIDS=$(comm -23 <(echo "$NEW_PIDS" | sort -u) <(echo "$LIMITED_PIDS" | sort -u) | grep -v '^$')   # PIDs in queue

	for i in $QUEUE_PIDS
	do
		cpulimit -p $i -l $CPU_LIMIT -z &   # Limit new violating processes
	done
done