cputemp

#!/bin/bash
#
# cputemp	Show CPU temperatures. MSR specific (currently Intel).
#
# This was written for use in a Xen guest (AWS EC2).
#
# USAGE: cputemp [-hu] [interval [count]]
#
# Temperatures are printed in degrees Celsius, per-CPU.
#
# This uses the CPU Model Specific Register to read per-cpu temperature
# information. The way the MSR is read is processor specific. If you want to run
# this on AMD or other CPU types, the MSR definitions section will need editing.
#
# Thanks to Ryan Cox, for the basic example of doing this:
# http://lists.us.dell.com/pipermail/linux-poweredge/2010-December/043786.html
#
# REQUIREMENTS: awk, rdmsr (from msr-tools)
#
# COPYRIGHT: Copyright (c) 2014 Brendan Gregg.
#
#  This program is free software; you can redistribute it and/or
#  modify it under the terms of the GNU General Public License
#  as published by the Free Software Foundation; either version 2
#  of the License, or (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with this program; if not, write to the Free Software Foundation,
#  Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
#
#  (http://www.gnu.org/copyleft/gpl.html)
#
# 12-Sep-2014   Brendan Gregg   Created this.
# 13-Feb-2018	   "      "	Added -a for average temp.

### MSR definitions
MSR_TEMPERATURE_TARGET=0x1a2
MSR_TEMPERATURE_TARGET_MASK=23:16
IA32_THERM_STATUS=0x19c
IA32_THERM_STATUS_MASK=22:16

### sanity check
family=$(awk '/cpu family/ { print $NF; exit }' /proc/cpuinfo)
if (( family != 6 )); then
	echo >&2 "WARNING: CPU family $family not recognized (not Intel?):"
	head >&2 /proc/cpuinfo
	echo >&2 "WARNING: continuining, but data is probably wrong."
	echo >&2 "WARNING: edit this script to use the correct MSRs."
fi

### options
opt_avg=0
opt_util=0
ncpus=$(nproc --all)
interval=1
count=1

function usage {
	cat <<-END >&2
	USAGE: cputemp [-ahu] [interval [count]]
	               -h         # USAGE message
	               -a         # average temperature only
	               -u         # include average CPU utilization %
	Temperatures are shown in degrees Celsius
END
	exit
}

while getopts ahu opt
do
	case $opt in
	a)	opt_avg=1 ;;
	u)	opt_util=1 ;;
	h|?)	usage ;;
	esac
done

shift $(( $OPTIND - 1 ))
if (( $# )); then
	interval=$1
	shift
	(( count = 7 * 24 * 3600 ))
	(( $# )) && count=$1
fi

### check access
if [[ "$USER" != "root" ]]; then
	echo >&2 "ERROR: needs root access. Exiting."
	exit 1
fi

if ! /sbin/modprobe msr; then
	echo >&2 "ERROR: modprobe msr. Missing msr-tools package? Exiting."
	exit 1
fi

cd /dev/cpu

### heading
head=
(( opt_util )) && head="AvgUtil(%) "
i=0
if (( opt_avg )); then
	head="${head}AvgTemp(C)"
else
	while (( i++ < ncpus )); do
		head="${head}CPU$i"
		(( i != ncpus )) && head="$head "
	done
fi
echo $head

### main
n=0
while (( n++ < count )); do
	out=

	# measure and print CPU utilization
	if (( opt_util )); then
		set -- $(awk '$1 == "cpu" { print $0; exit }' /proc/stat)
		(( used0 = $2 + $3 + $4 + $6 + $7 ))
		sleep $interval
		set -- $(awk '$1 == "cpu" { print $0; exit }' /proc/stat)
		(( used1 = $2 + $3 + $4 + $6 + $7 ))
		(( used = (used1 - used0) / ncpus ))
	else
		(( n != count )) && sleep $interval
	fi

	# fetch and print CPU temperatures
	cpu=0
	sum=0
	out=""
	while (( cpu < ncpus )); do
		tt=$(rdmsr -p$cpu -f $MSR_TEMPERATURE_TARGET_MASK \
		    -d $MSR_TEMPERATURE_TARGET)
		do=$(rdmsr -p$cpu -f $IA32_THERM_STATUS_MASK \
		    -u $IA32_THERM_STATUS)
		(( temp = tt - do ))
		(( sum += temp ))
		out="${out}$temp "
		(( cpu++ ))
	done
	(( opt_util )) && printf "$used "
	if (( opt_avg )); then
		awk -v sum=$sum -v ncpus=$ncpus 'BEGIN { printf("%.1f\n", sum / ncpus); }'
	else
		echo $out
	fi
done