devstack/tools/peakmem_tracker.sh
Ian Wienand ada886dd43 Don't mix declaration and set of locals
Ia0957b47187c3dcadd46154b17022c4213781112 proposes to have bashate
find instances of setting a local value.  The issue is that "local"
always returns 0, thus hiding any failure in the commands running to
set the variable.

This is an automated replacement of such instances

Depends-On: I676c805e8f0401f75cc5367eee83b3d880cdef81
Change-Id: I9c8912a8fd596535589b207d7fc553b9d951d3fe
2015-10-07 17:03:32 +11:00

99 lines
2.9 KiB
Bash
Executable File

#!/bin/bash
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
set -o errexit
# time to sleep between checks
SLEEP_TIME=20
# MemAvailable is the best estimation and has built-in heuristics
# around reclaimable memory. However, it is not available until 3.14
# kernel (i.e. Ubuntu LTS Trusty misses it). In that case, we fall
# back to free+buffers+cache as the available memory.
USE_MEM_AVAILBLE=0
if grep -q '^MemAvailable:' /proc/meminfo; then
USE_MEM_AVAILABLE=1
fi
function get_mem_available {
if [[ $USE_MEM_AVAILABLE -eq 1 ]]; then
awk '/^MemAvailable:/ {print $2}' /proc/meminfo
else
awk '/^MemFree:/ {free=$2}
/^Buffers:/ {buffers=$2}
/^Cached:/ {cached=$2}
END { print free+buffers+cached }' /proc/meminfo
fi
}
# whenever we see less memory available than last time, dump the
# snapshot of current usage; i.e. checking the latest entry in the
# file will give the peak-memory usage
function tracker {
local low_point
low_point=$(get_mem_available)
while [ 1 ]; do
local mem_available
mem_available=$(get_mem_available)
if [[ $mem_available -lt $low_point ]]; then
low_point=$mem_available
echo "[[["
date
echo "---"
# always available greppable output; given difference in
# meminfo output as described above...
echo "peakmem_tracker low_point: $mem_available"
echo "---"
cat /proc/meminfo
echo "---"
# would hierarchial view be more useful (-H)? output is
# not sorted by usage then, however, and the first
# question is "what's using up the memory"
#
# there are a lot of kernel threads, especially on a 8-cpu
# system. do a best-effort removal to improve
# signal/noise ratio of output.
ps --sort=-pmem -eo pid:10,pmem:6,rss:15,ppid:10,cputime:10,nlwp:8,wchan:25,args:100 |
grep -v ']$'
echo "]]]"
fi
sleep $SLEEP_TIME
done
}
function usage {
echo "Usage: $0 [-x] [-s N]" 1>&2
exit 1
}
while getopts ":s:x" opt; do
case $opt in
s)
SLEEP_TIME=$OPTARG
;;
x)
set -o xtrace
;;
*)
usage
;;
esac
done
shift $((OPTIND-1))
tracker