awk求某一列的最大值

# 日志内容
2022-01-18 23:59:58,397 I 356615016 UserEnterRoom ok roomId= 120922 user= 1850158 userCount= 14 reconnect= False

# 命令
awk 'BEGIN{max = 0}{if($12 > max) max = $12}END{print max}' room.txt