Cacti/Bcache

bcache Host

Add to your /etc/snmp/snmpd.conf

exec bcache /etc/snmp/bcache.sh

Create /etc/snmp/bcache.sh

#!/bin/bash

PATH='/sys/fs/bcache'

if [ ! -d ${PATH} ]; then
  echo "Error: bcache not loaded"
  exit 1
fi

DIRTY_DATA=0
BYPASSED=0

get_dirty_data () {
  for dev in "${PATH}/${1}/bdev*/"; do
    local size=$(<${dev}/dirty_data)
    local bytes=$(/usr/bin/numfmt --from=iec ${size})
    DIRTY_DATA=$(( ${DIRTY_DATA} + ${bytes} ))
  done
}

get_cache_ratio () {
  local cache_ratio=""
  for dev in "${PATH}/${1}/bdev*/"; do
    local hits=$(<${dev}/stats_${2}/cache_hits)
    local misses=$(<${dev}/stats_${2}/cache_misses)
    local dev_ratio=$(( 100 * ${hits} / (${hits} + ${misses}) ))
    if [ -z ${cache_ratio} ]; then
      cache_ratio=${dev_ratio}
    fi
    cache_ratio=$(( (${cache_ratio} + ${dev_ratio}) / 2 )) 
  done
  eval CACHE_RATIO_${2}=${cache_ratio}
}

get_cache_request () {
  for dev in "${PATH}/${1}/bdev*/"; do
    local value=$(<${dev}/stats_five_minute/cache_${2})
    eval CACHE_REQUEST_${2}=$(( $CACHE_REQUEST_${2} + ${value} ))
  done
}

get_bypassed () {
  for dev in "${PATH}/${1}/bdev*/"; do
    local size=$(<${dev}/stats_five_minute/bypassed)
    local bytes=$(/usr/bin/numfmt --from=iec ${size}) 
    BYPASSED=$(( ${BYPASSED} + ${bytes} ))
  done
}

for cache in "${PATH}/*/"; do
  uuid=$(/usr/bin/basename ${cache})
  get_dirty_data ${uuid}
  get_cache_ratio ${uuid} five_minute
  get_cache_ratio ${uuid} hour
  get_cache_ratio ${uuid} day
  get_cache_ratio ${uuid} total
  get_cache_request ${uuid} hits
  get_cache_request ${uuid} misses
  get_cache_request ${uuid} bypass_hits
  get_cache_request ${uuid} bypass_misses
  get_cache_request ${uuid} miss_collisions
  get_cache_request ${uuid} readaheads
  get_bypassed ${uuid}
done

echo "dirty_data:${DIRTY_DATA} \
  ratio-5m:${CACHE_RATIO_five_minute} \
  ratio-1h:${CACHE_RATIO_hour} \
  ratio-1d:${CACHE_RATIO_day} \
  ratio-total:${CACHE_RATIO_total} \
  request_hits:${CACHE_REQUEST_hits} \
  request_misses:${CACHE_REQUEST_misses} \
  request_bypass_hits:${CACHE_REQUEST_bypass_hits} \
  request_bypass_misses:${CACHE_REQUEST_bypass_misses} \
  request_miss_collisions:${CACHE_REQUEST_miss_collisions} \
  request_readaheads:${CACHE_REQUEST_readaheads} \
  bypassed:${BYPASSED}"

exit 0

Cacti Host

/usr/share/cacti/resource/scripts/get_bcache.sh

#!/bin/bash

if [ ${#} -ne 3 ]; then
  echo "Usage: $0 <host> <community>"
  exit 0
fi

snmptable -CH -Cf '#' -c${2} -v1 ${1} .1.3.6.1.4.1.2021.8 | cut -d '#' -f5

Data Template

tbc