[MySQL] MySQLinnodb_monitor及死锁检测

• 　　对于死锁，MySQL并没有提供提供直接的变量来表示。对于5.5版本之后的performance_shcema可以提供锁的详细信息（但我们还是5.0呢），对于InnoDB自带的监控器 Innodb_lock_monitor 其输出总是输出到错误日志中，不方便进行对比。
  

New_deadlock() {
  new_line_tile=$(grep -n "LATEST DETECTED DEADLOCK" $1 | cut -d ':' -f 1)
  new_line_time=$(echo "$new_line_tile + 2" | bc)
  last_dect_time="$(head -n $new_line_time $1 | tail -n 1) ###截取死锁发生的时间戳
                       
  [ -e $2 ] || cp $1 $2 #拿这次输出信息，和上次输出信息对比；如果是第一次检测，将这次输出信息cp作为上次输出信息
                    
  old_line_tile=$(grep -n "LATEST DETECTED DEADLOCK" $2 | cut -d ':' -f 1)
                    
  if [ -z $old_line_tile ];then
    echo 1
    mv $1  $2  ##判断上次输出是否为死锁，不是的话，直接返回1 表明最近一次是新的死锁。并将 此次输出信息重命名
    exit 1
  else    ##否则对比两次的时间戳
    old_line_time=$(echo "$old_line_tile + 2" | bc) 
    old_last_dect_time="$(head -n $old_line_time  $2 | tail -n 1)"
    mv $1  $2 #输出信息为下一次检测做准备
                    
    if [ "$last_dect_time" = "$old_last_dect_time" ];then
    echo 0
    else
    cp $1 /tmp/$1_detail #已判定为死锁，需要保留作案信息
    echo 1
    fi
  fi
}
deadlock_check() {
  case $1 in
  1)
  $MYSQL_BIN -u $user -p$password  -S $SOC1 -e "show engine innodb status\G" > /tmp/innodb_status_1_$dthm
  have_dead_lock=$(grep -c  "LATEST DETECTED DEADLOCK" /tmp/innodb_status_1_$dthm)
  #判断这次检测是否包含死锁信息，包含的话 让 New_dead_lock 做死锁对比否则 返回0
  if [ $have_dead_lock -gt 0 ];then
    New_deadlock /tmp/innodb_status_1_$dthm /tmp/innodb_status_1_$dt
  else
    echo 0
  fi;;
  2)
  $MYSQL_BIN -u $user -p$password  -S $SOC2 -e "show engine innodb status\G" > /tmp/innodb_status_2_$dthm
  have_dead_lock=$(grep -c  "LATEST DETECTED DEADLOCK" /tmp/innodb_status_2_$dthm)
  if [ $have_dead_lock -gt 0 ];then
    New_deadlock /tmp/innodb_status_2_$dthm /tmp/innodb_status_2_$dt
  else
    echo 0
  fi;;
  3)
  $MYSQL_BIN -u $user -p$password  -S $SOC3 -e "show engine innodb status\G" > /tmp/innodb_status_3_$dthm
  have_dead_lock=$(grep -c  "LATEST DETECTED DEADLOCK" /tmp/innodb_status_3_$dthm)
  if [ $have_dead_lock -gt 0 ];then
    New_deadlock  /tmp/innodb_status_3_$dthm /tmp/innodb_status_3_$dt
  else
    echo 0
  fi;;
  4)
  $MYSQL_BIN -u $user -p$password  -S $SOC4 -e "show engine innodb status\G" > /tmp/innodb_status_4_$dthm
  have_dead_lock=$(grep -c  "LATEST DETECTED DEADLOCK" /tmp/innodb_status_4_$dthm)
  if [ $have_dead_lock -gt 0 ];then
    New_deadlock /tmp/innodb_status_4_$dthm /tmp/innodb_status_4_$dt
  else
    echo 0
  fi;;
  *)
  echo $ERROR
  exit 1;;
  esac
}
case  $1中的变量是针对不同机器上多个实例的情况，传送socket参数