mem-metrics

mem-metrics.sh

#!/bin/bash

mem_total=$(cat /proc/meminfo | awk '/^MemTotal/ { print $2; }')
mem_free=$(cat /proc/meminfo | awk '/^MemFree/ { print $2; }')
swap_free=$(cat /proc/meminfo | awk '/^SwapFree/ { print $2; }')
swap_total=$(cat /proc/meminfo | awk '/^SwapTotal/ { print $2; }')

slab_size=$(cat /proc/meminfo | awk '/^Slab/ { print $2; }')
dcache_size=$(cat /proc/meminfo | awk '/^Cached/ { print $2; }')
swapcache_size=$(cat /proc/meminfo | awk '/^SwapCached/ { print $2; }')
buffers_size=$(cat /proc/meminfo | awk '/^Buffers/ { print $2; }')
mem_free_no_cache=$(( $mem_free + $swapcache_size + $buffers_size))
swap_used=$(( $swap_total - $swap_free ))

pages_shared=$(cat /sys/kernel/mm/ksm/pages_shared)
pages_sharing=$(cat /sys/kernel/mm/ksm/pages_sharing)
pages_unshared=$(cat /sys/kernel/mm/ksm/pages_unshared)
pages_volatile=$(cat /sys/kernel/mm/ksm/pages_volatile)
page_size=$(getconf PAGESIZE)
if [ "${pages_shared}" != 0 ]; then
  ratio_sharing_to_shared=$(echo "scale=2;$pages_sharing / $pages_shared"|bc);
else
  ratio_sharing_to_shared=0
fi
if [ "${pages_unshared}" != 0 ]; then
  ratio_unshared_to_sharing=$(echo "scale=2;$pages_unshared / $pages_sharing"|bc);
else
  ratio_unshared_to_sharing=0
fi
ksm_saved=$(echo "scale=0;$pages_sharing * $page_size / 1024"|bc);

if [ -d /proc/spl/kstat/zfs ]; then
  zfs_arc_shrink_shift=`cat /sys/module/zfs/parameters/zfs_arc_shrink_shift`
  zfs_arc_shrink_size=$(( $mem_total / (1<<$zfs_arc_shrink_shift) ))
  arc_size=$(cat /proc/spl/kstat/zfs/arcstats | awk '/^size/ { print $3; }')
  arc_mfu_size=$(cat /proc/spl/kstat/zfs/arcstats | awk '/^mfu_size/ { print $3; }')
  arc_mfu_ghost_size=$(cat /proc/spl/kstat/zfs/arcstats | awk '/^mfu_ghost_size/ { print $3; }')
  arc_mru_size=$(cat /proc/spl/kstat/zfs/arcstats | awk '/^mru_size/ { print $3; }')
  arc_mru_ghost_size=$(cat /proc/spl/kstat/zfs/arcstats | awk '/^mru_ghost_size/ { print $3; }')

  arc_hits=$(grep '^hits' /proc/spl/kstat/zfs/arcstats | awk '{print $3}')
  arc_misses=$(grep '^misses' /proc/spl/kstat/zfs/arcstats | awk '{print $3}')
  arc_total=$(($arc_hits + $arc_misses))
  arc_hit_rate=$(($arc_hits * 100 / $arc_total))
fi

hostname=$(hostname)
epoch=$(date +%s)
echo "${hostname}.meminfo.mem_total ${mem_total} ${epoch}"
echo "${hostname}.meminfo.slab_size ${slab_size} ${epoch}"
echo "${hostname}.meminfo.dcache_size ${dcache_size} ${epoch}"
echo "${hostname}.meminfo.swapcache_size ${swapcache_size} ${epoch}"
echo "${hostname}.meminfo.buffers_size ${buffers_size} ${epoch}"
echo "${hostname}.meminfo.mem_free ${mem_free} ${epoch}"
echo "${hostname}.meminfo.mem_free_no_cache ${mem_free_no_cache} ${epoch}"
echo "${hostname}.meminfo.mem_swap_free ${swap_free} ${epoch}"
echo "${hostname}.meminfo.mem_swap_used ${swap_used} ${epoch}"

echo "${hostname}.meminfo.ksm_saved ${ksm_saved} ${epoch}"
echo "${hostname}.meminfo.ksm_shared  ${pages_shared} ${epoch}"
echo "${hostname}.meminfo.ksm_sharing ${pages_sharing} ${epoch}"
echo "${hostname}.meminfo.ksm_unshared ${pages_unshared} ${epoch}"
echo "${hostname}.meminfo.ksm_volatile ${pages_volatile} ${epoch}"
echo "${hostname}.meminfo.ksm_sharing_ratio ${ratio_sharing_to_shared} ${epoch}"
echo "${hostname}.meminfo.ksm_unshared_ratio ${ratio_unshared_to_sharing} ${epoch}"

if [ -d /proc/spl/kstat/zfs ]; then
  echo "${hostname}.meminfo.arc_hits ${arc_hits} ${epoch}"
  echo "${hostname}.meminfo.arc_misses ${arc_misses} ${epoch}"
  echo "${hostname}.meminfo.arc_hit_rate ${arc_hit_rate} ${epoch}"
  echo "${hostname}.meminfo.arc_size ${arc_size} ${epoch}"
  echo "${hostname}.meminfo.arc_mfu_size ${arc_mfu_size} ${epoch}"
  echo "${hostname}.meminfo.arc_mfu_ghost_size ${arc_mfu_ghost_size} ${epoch}"
  echo "${hostname}.meminfo.zfs_arc_shrink_size ${zfs_arc_shrink_size} ${epoch}"
fi