RouterOS v6.29 新功能 “FastTrack”
从v6.29rc9, 将引入新的功能FastTrack，根据官方解释可以使你的路由器Firewall/NAT性能提升5倍，6.29rc9大致新增内容如下：
*) ipv4 fasttrack fastpath – accelerates connection tracking and nat for marked connections (more than 5x performance improvement compared to regular slow path conntrack/nat) – currently limited to TCP/UDP only;
*) added ~fasttrack-connection~ firewall action in filter/mangle tables for marking connections as fasttrack;
*) added fastpath support for bridge interfaces – packets received and transmitted on bridge interface can go fastpath (previously only bridge forwarded packets could go fastpath);
*) packets now can go half-fastpath – if input interface supports fastpath and packet gets forwarded in fastpath but output interface does not support fastpath or has interface queue other than only-hw-queue packet gets converted to slow path only at the dst interface transmit time;
官方介绍FastTrack= FastPath + Conntrack，主要特点为：
1、FastTrack加速指定的连接跟踪条目的数据包处理
2、FastTrack具备Full NAT支持
3、与普通的连接跟踪和NAT性能提升5倍
4、firewall filter/mangle菜单下新增fasttrack-connection选项
5、支持IPv4 TCP/UDP连接跟踪条目
6、工作方式类似于“mark-connection” 添加连接跟踪标记，并允许数据包被定义为FastTrack
7、并非所有的数据包都能被FastTrack处理，有一些数据包将仍然使用普通的Conntrack（连接跟踪）
x86是不支持FastTrack（因为FastPath不支持），经过测试FastTrack使用上有较多限制，例如在VLAN、PPP等协议启用后，不能开启