code: public static function cpuCoreInfo() 
      {
          $cores = array();
          if(false !== ($data = @file('/proc/stat'))){
              foreach($data as $line ) {
                  if( preg_match('/^cpu[0-9]/', $line) ){
                      $info = explode(' ', $line);
                      $cores[]=array(
                          'user'      => $info[1],
                          'nice'      => $info[2],
                          'sys'       => $info[3],
                          'idle'      => $info[4],
                          'iowait'    => $info[5],
                          'irq'       => $info[6],
                          'softirq'   => $info[7]
                      );
                  }
              }
          }
          
          return $cores;
          
      }
docs: Server cpu cores information
  @return array