extras: scripts to control CPU/MEMORY for any gluster daemon during runtime

Problem: Sometime gluster daemons like glustershd can consume a lot of cpu and/
or memory if there is a large amount of data/ entries to be healed.

Solution: Until we have some form of throttling/ QoS mechanisms built into
gluster, we can use control groups for regulating cpu and memory of any gluster
daemon using control-cpu-load.sh and control-mem.sh scripts respectively.

Test:    To test the control-cpu-load.sh script follow below procedure:
         1) Setup distribute replica environment
         2) Selfheal daemon off
         3) Down one node from replica nodes
         4) Create millions of files from mount point
         5) Start down node
         6) Check cpu usage for shd process in top command
         7) Run script after provide shd pid with CPU quota value
         8) Check again cpu usage for shd process in top command

Note: control-mem.sh script can cap the memory usage of the process to the set
limit, beyond which the process gets blocked. It resumes either when the memory
usage comes down or if the limit is increased.

BUG: 1496335
Change-Id: Id73c36b73ca600fa9f7905d84053d1e8633c996f
Signed-off-by: Mohit Agrawal <moagrawa@redhat.com>

1 files changed, 128 insertions, 0 deletions

diff --git a/extras/control-mem.sh b/extras/control-mem.sh
new file mode 100755
index 00000000000..38aa2a08748
--- /dev/null
+++ b/extras/control-mem.sh
@@ -0,0 +1,128 @@
+#!/bin/bash
+
+USAGE="This commands provides a utility to control MEMORY utilization for any
+gluster daemon.In this, we use cgroup framework to configure MEMORY limit for
+a process. Before running this script, make sure that daemon is running.Every
+time daemon restarts, it is required to rerun this command to set memory limit
+(in bytes) on new daemon process id.User can enter any value between 100
+(in Mega bytes) to 8000000000000 for Memory limit in Mega bytes.
+Memory limit value is depends on how much maximum memory user wants to restrict
+for specific daemon process.If a process will try to consume memore more than
+configured value then cgroup will hang/sleep this task and to resume the task
+rerun the script with new increase memory limit value ."
+
+if [  $# -ge 1 ]; then
+  case $1 in
+    -h|--help) echo " " "$USAGE" | sed -r -e 's/^[ ]+//g'
+               exit 0;
+               ;;
+    *) echo "Please Provide correct input for script."
+       echo "For help correct options are -h of --help."
+       exit 1;
+               ;;
+  esac
+fi
+
+DIR_EXIST=0
+LOC="/sys/fs/cgroup/memory/system.slice/glusterd.service"
+echo "Enter Any gluster daemon pid for that you want to control MEMORY."
+read daemon_pid
+
+if expr ${daemon_pid} + 0 > /dev/null 2>&1 ;then
+  CHECK_PID=$(pgrep -f gluster | grep ${daemon_pid})
+  if [ -z "${CHECK_PID}" ]; then
+    echo "No daemon is running or pid ${daemon_pid} does not match."
+    echo "with running gluster processes."
+    exit 1
+  fi
+else
+  echo "Entered daemon_pid is not numeric so Rerun the script."
+  exit 1
+fi
+
+
+if [ -f ${LOC}/tasks ]; then
+  CHECK_CGROUP=$(grep ${daemon_pid} ${LOC}/tasks)
+  if [ ${CHECK_CGROUP} ] ;then
+    echo "pid ${daemon_pid} is attached with default glusterd.service cgroup."
+  fi
+fi
+
+cgroup_name=cgroup_gluster_${daemon_pid}
+if [ -f ${LOC}/${cgroup_name}/tasks ];then
+  CHECK_CGROUP=$(grep ${daemon_pid} ${LOC}/${cgroup_name}/tasks)
+  if [ ${CHECK_CGROUP} ]; then
+    val=`cat ${LOC}/${cgroup_name}/memory.limit_in_bytes`
+    mval=$((val / 1024 / 1024))
+    echo "pid ${daemon_pid} is already attached ${cgroup_name} with mem value ${mval}."
+    echo "Press n if you don't want to reassign ${daemon_pid} with new mem value."
+    DIR_EXIST=1
+  else
+    echo "pid ${daemon_pid} is not attached with ${cgroup_name}."
+  fi
+fi
+
+read -p "If you want to continue the script to attach daeomon with new cgroup. Press (y/n)?" choice
+case "$choice" in
+  y|Y ) echo "yes";;
+  n|N ) echo "no";exit;;
+  * ) echo "invalid";exit;;
+esac
+
+systemctl set-property glusterd.service CPUShares=1024
+
+if [ ${DIR_EXIST} -eq 0 ];then
+  echo "Creating child cgroup directory '${cgroup_name} cgroup' for glusterd.service."
+  mkdir -p ${LOC}/${cgroup_name}
+  if [ ! -f ${LOC}/${cgroup_name}/tasks ];then
+    echo "Not able to create ${LOC}/${cgroup_name} directory so exit."
+    exit 1
+  fi
+fi
+
+echo "Enter Memory value in Mega bytes [100,8000000000000]:  "
+
+read mem_value
+if expr ${mem_value} + 0 > /dev/null 2>&1 ;then
+  if [ ${mem_value} -lt 100 ] || [ ${mem_value} -gt 8000000000000 ]; then
+    echo "Entered memory value is not correct,it should be in the range ."
+    echo "100-8000000000000, Rerun the script with correct value ."
+    exit 1
+  else
+    echo "Entered memory limit value is ${mem_value}."
+  fi
+else
+  echo "Entered memory value is not numeric so Rerun the script."
+  exit 1
+fi
+
+mem_value=$(($mem_value * 1024 * 1024))
+if [ ${DIR_EXIST} -eq 0 ];then
+  echo "Setting ${mem_value} to memory.limit_in_bytes for ${LOC}/${cgroup_name}."
+  echo ${mem_value} > ${LOC}/${cgroup_name}/memory.limit_in_bytes
+  #Set memory value to memory.memsw.limit_in_bytes
+  echo ${mem_value} > ${LOC}/${cgroup_name}/memory.memsw.limit_in_bytes
+  # disable oom_control so that kernel will not send kill signal to the
+  # task once limit has reached
+  echo 1 > ${LOC}/${cgroup_name}/memory.oom_control
+else
+  #Increase mem_value to memory.memsw.limit_in_bytes
+  echo ${mem_value} > ${LOC}/${cgroup_name}/memory.memsw.limit_in_bytes
+  echo "Increase ${mem_value} to memory.limit_in_bytes for ${LOC}/${cgroup_name}."
+  echo ${mem_value} > ${LOC}/${cgroup_name}/memory.limit_in_bytes
+  # disable oom_control so that kernel will not send kill signal to the
+  # task once limit has reached
+  echo 1 > ${LOC}/${cgroup_name}/memory.oom_control
+fi
+
+if ps -T -p ${daemon_pid} | grep gluster > /dev/null; then
+  for thid in `ps -T -p ${daemon_pid} | grep gluster | awk -F " " '{print $2}'`;
+    do
+      echo ${thid} > ${LOC}/${cgroup_name}/tasks ;
+    done
+  if cat /proc/${daemon_pid}/cgroup | grep -iw ${cgroup_name} > /dev/null; then
+    echo "Tasks are attached successfully specific to ${daemon_pid} to ${cgroup_name}."
+  else
+    echo "Tasks are not attached successfully."
+  fi
+fi