Add a script to bind the MySQL process to a CPU set
This script creates a specified CPU set and bind a running MySQL process
to the set. When running with option "-r", the script restarts MySQL
first before performing the binding. Hence this script should act as a
wrapper script for starting MySQL if we want to limit the CPU usage of
MySQL.
BUG=chromium-os:33582
TEST=local tests
Change-Id: I48b0ea9b838e0de3569c429c3b4fccede20f67ae
Reviewed-on: https://gerrit.chromium.org/gerrit/30977
Commit-Ready: Yu-Ju Hong <yjhong@chromium.org>
Reviewed-by: Yu-Ju Hong <yjhong@chromium.org>
Tested-by: Yu-Ju Hong <yjhong@chromium.org>
diff --git a/site_utils/bind_mysql_to_cpuset.sh b/site_utils/bind_mysql_to_cpuset.sh
new file mode 100755
index 0000000..60d5d66
--- /dev/null
+++ b/site_utils/bind_mysql_to_cpuset.sh
@@ -0,0 +1,244 @@
+#!/bin/bash
+
+# Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# This script creates a CPU set and binds the MySQL process to the
+# set. It restarts MySQL if specified in the option. This script needs
+# to be run with "sudo".
+
+set -e # Exit if any function returns a non-zero value.
+set -o nounset # Exit if any variable is used unset.
+
+MYSQL_PATH='/etc/init.d/mysql.server'
+MYSQL_PID_PATH='/var/lib/mysql/atlantis1.mtv.corp.google.com.pid'
+MYSQL_PROC_NAME='mysqld'
+
+# The directory where we mount the cpuset virutal file system to.
+MOUNT_DIR='/dev/cpuset'
+# The base cpuset directory for mysql.
+MYSQL_CPUSET='mysql'
+# CPUs in MySQL cpuset. E.g. 0-2,7,12-14.
+MYSQL_DEFAULT_CPUS=10-15
+
+
+# Display usage.
+function usage() {
+ echo -e "Usage: $0 [-c <CPUs>] [-p <PID>] [-r] [-d]\n"
+ echo -e "Create and bind the MySQL process to a specified CPU set.\n"
+ echo -e "Options:"
+ echo -e " -c <CPUs> Specify a list of CPUs to be used. E.g. 0-2,7,12-14"
+ echo -e " (Default: $MYSQL_DEFAULT_CPUS)."
+ echo -e " -d Delete the CPU set. This option kills the current"
+ echo -e " MySQL process and delete the CPU set. It does not"
+ echo -e " restart MySQL nor create a new CPU set. (Default:"
+ echo -e " disabled)."
+ echo -e " -p <PID> Bind <PID> to the cpuset (Default: the script searches"
+ echo -e " for the MySQL PID automatically)."
+ echo -e " -r Restart MySQL (Default: disabled)."
+ echo -e " -h Display this usage information."
+ echo -e "\n"
+}
+
+function print_info() {
+ msg=$1
+ echo "INFO: "$msg
+}
+
+function print_error() {
+ msg=$1
+ echo "ERROR: "$msg
+}
+
+# Run and print out the command if the silent flag is not set (the default).
+# Usage: run_cmd <cmd> [slient]
+function run_cmd() {
+ cmd=""
+ slient=0
+
+ if [ $# -gt 0 ]; then
+ cmd=$1
+ else
+ print_error "Empty command!"
+ return 1
+ fi
+
+ if [ $# -gt 1 ]; then
+ silent=$2
+ fi
+
+ if [ $slient -eq 0 ]; then
+ print_info "Running \"${1}\""
+ fi
+
+ # Print an error message if the command failed.
+ eval "$1" || { print_error "Failed to execute \"${cmd}\""; return 1; }
+}
+
+# Get the PID of the MySQL.
+function get_mysql_pid() {
+ local pid=""
+
+ if [ $# -gt 0 ]; then
+ # Use user-provided PID.
+ pid=$1
+ elif [ ! -z ${MYSQL_PID_PATH} -a -f ${MYSQL_PID_PATH} ]; then
+ # Get PID from MySQL PID file if it is set.
+ print_info "Getting MySQL PID from ${MYSQL_PID_PATH}..."
+ pid=$(cat $MYSQL_PID_PATH) || \
+ { print_error "No MySQL process found."; return 1; }
+ else
+ # Get PID of process named mysqld.
+ print_info "Searching for MySQL PID..."
+ # Ignore the return code to print out an error message.
+ pid=$(pidof $MYSQL_PROC_NAME) || \
+ { print_error "No MySQL process found."; return 1; }
+ fi
+
+ # Test if the PID is an integer
+ if [[ $pid != [0-9]* ]]; then
+ print_error "No MySQL process found."
+ return 1
+ fi
+
+ # Check if the PID is a running process.
+ if [ ! -d "/proc/${pid}" ]; then
+ print_error "No running MySQL process is found."
+ return 1
+ fi
+
+ _RET="$pid"
+ print_info "MySQL PID is ${pid}."
+}
+
+# Mount the cpuset virtual file system.
+function mount_cpuset() {
+ if (mount | grep "on ${MOUNT_DIR} type" > /dev/null)
+ then
+ print_info "${MOUNT_DIR} already mounted."
+ else
+ print_info "Mounting cpuset to $MOUNT_DIR."
+ run_cmd "mkdir -p ${MOUNT_DIR}"
+ run_cmd "mount -t cpuset none ${MOUNT_DIR}"
+ fi
+}
+
+
+function clean_all() {
+ local delete_msg="No"
+ print_info "Will Delete existing CPU set..."
+ echo -ne "WARNING: This operation will kill all running "
+ echo "processes in the CPU set."
+ echo -ne "Are you sure you want to proceed "
+ echo -ne "(type \"yes\" or \"Yes\" to proceed)? "
+ read delete_msg
+
+ mount_cpuset
+
+ local proc_list=""
+ local proc=""
+
+ if [ "$delete_msg" = "yes" -o "$delete_msg" = "Yes" ]; then
+ if [ -d "${MOUNT_DIR}/${MYSQL_CPUSET}" ]; then
+ proc_list=$(cat ${MOUNT_DIR}/${MYSQL_CPUSET}/cgroup.procs)
+ for proc in $proc_list; do
+ run_cmd "kill -9 ${proc}"
+ done
+ # Remove the CPU set directory.
+ run_cmd "rmdir ${MOUNT_DIR}/${MYSQL_CPUSET}"
+ # Unmount the cpuset virtual file system.
+ run_cmd "umount ${MOUNT_DIR}"
+ else
+ print_info "The CPU set does not exist."
+ return 1
+ fi
+ print_info "Done!"
+ else
+ # User does not wish to continue.
+ print_info "Aborting program."
+ fi
+}
+
+
+function main() {
+
+ local MYSQL_CPUS=$MYSQL_DEFAULT_CPUS
+ local RESTART_MYSQL_FLAG=0
+ local DELETE_CPUSET_FLAG=0
+ local MYSQL_PID=""
+
+ # Parse command-line arguments.
+ while getopts ":c:dhp:r" opt; do
+ case $opt in
+ c)
+ MYSQL_CPUS=$OPTARG
+ ;;
+ d)
+ DELETE_CPUSET_FLAG=1
+ ;;
+ h)
+ usage
+ return 0
+ ;;
+ p)
+ MYSQL_PID=$OPTARG
+ ;;
+ r)
+ RESTART_MYSQL_FLAG=1
+ ;;
+ \?)
+ echo "Invalid option: -$OPTARG" >&2
+ usage
+ return 1
+ ;;
+ :)
+ echo "Option -$OPTARG requires an argument." >&2
+ usage
+ return 1
+ ;;
+ esac
+ done
+
+
+ # Clean up and exit if the flag is set.
+ if [ $DELETE_CPUSET_FLAG -eq 1 ]; then
+ clean_all
+ return 0
+ fi
+
+ # Restart MySQL.
+ if [ $RESTART_MYSQL_FLAG -eq 1 ]; then
+ print_info "Restarting MySQL..."
+ $MYSQL_PATH restart
+ fi
+
+
+ # Get PID of MySQL.
+ get_mysql_pid "$MYSQL_PID"
+ MYSQL_PID=$_RET
+
+ mount_cpuset
+
+ # Make directory for MySql.
+ print_info "Making a cpuset for MySQL..."
+ run_cmd "mkdir -p ${MOUNT_DIR}/${MYSQL_CPUSET}"
+
+ # Change working directory.
+ run_cmd "cd ${MOUNT_DIR}/${MYSQL_CPUSET}"
+
+ # Update the CPUs to use in the CPU set. Note that we use /bin/echo
+ # explicitly (instead of "echo") because it displays write errors.
+ print_info "Updating CPUs in the cpuset..."
+ run_cmd "bash -c \"/bin/echo ${MYSQL_CPUS} > cpus\""
+
+ # Attach/Rebind MySQL process to the cpuset. Note that this command
+ # can only attach one PID at a time. This needs to be run every time
+ # after the CPU set is modified.
+ print_info "Bind MySQL process to the cpuset..."
+ run_cmd "bash -c \"/bin/echo ${MYSQL_PID} > tasks\""
+
+ print_info "Done!"
+}
+
+main "$@"