作者：徐继哲 <http://www.billxu.com>


即使是熟悉FreeBSD的朋友都不一定知道George Neville Neil是谁，但是或许我们都听说过一本叫<<The Design and Implementation of the FreeBSD Operating System>>的书。没错，Geroge使这本书的作者之一，另外一位作者就是大名鼎鼎的MARSHALL KIRK MCKUSICK了。George出生于纽约，现在工作、生活在日本东京。作为FreeBSD committer，George主要关注FreeBSD网络部分的设计与实现。目前George在Yahoo公司工作，主要负责源代码安全审计以及相关的培训工作，另外，George还参与评估公司收购对象的重任。

http://www.billxu.com/friend/gnn/PICT0078.JPGNeville Neil畅谈FreeBSD" />

从左到右分别是：Delphij, Gorege and Bill

Geroge此次来北京是出于Yahoo的工作原因，他将巡视Yahoo在亚太地区的各个分公司，在各地做代码审计、安全编程的培训等工作。在出发之前 George在FreeBSD Committers的邮件列表里公布了他此次的行程安排。于是delphij同学就想搞一个小型的FreeBSD的讨论会。最近一段时间，我和 delphij同学在工作上都非常忙碌，他在倒腾免费邮箱外层MX服务器的事情，我在策划“重建紫禁城”计划。所以没有足够的精力来策划一个稍微大一点规模的聚会，感到有点遗憾，最终参加聚会的人数大概在20人左右。

聚会的地点是新浪网20层1号会议室。在此我要感谢公司的CTO，李嵩波先生，正是他对于自由软件的一贯支持，才使我们一直都有宽松的活动环境。 Delphij的主题是关于FreeBSD Release Engineering, 同时简单回顾了FreeBSD的历史，属于普及性质的讲座。George利用会议间歇，写了他要演讲的内容，主要是关于网络方面的。

George的演讲稿：

Current Projects in FreeBSD

    The Good News

    Port to Xen

    More chip support

    More wireless support

    Hardware Performance Monitoring (HWPMC)

    Continuing network performance improvements

    Clean up of IPv6, IPSec and FAST_IPSEC

    SCTP



The Good News

    Moore’s law is dead

    SMP turned out to be a good long term strategy

    All chips now going multi-core

    SMP absolutely required to continue to get performance gains



Xen Port

    Xen is an open source virtualization system

    Requires changes to the operating system for the operating system to be hosted

    A port is underway



More Processor Support

    ARM9 work now ongoing

    PowerPC work now ongoing

    Various SPARC processors including Niagra



Wireless Support

    Work being done by Sam Leffler and others

    About to integrate more support for vlans

    More hardware support being added slowly

    Depends on hardware availability and developer time



HWPMC

    Hardware Performance Monitoring Code

    Uses chip specific counters to give a better idea of what’s going on in the system and in your program

    There is a version currently in the system

    Support on AMD and Intel processors

    More tools being written and necessary

    Can eventually replace gprof



Network Performance

    Moving to SMP slowed down the performance of many system

    Networking was the last one to receive attention

    The goal is to remove the GIANT lock from all code

    GIANT Lock currently surrounds

        Kame IPv6 and IPSec

        Some ATM subsystems

    Current work is around reference counting sockets



Network Performance Status

    All TCP/IP v4 code is now fine grained lock

    One ATM stack will remain and be fine grained locked

    IPX/SPX stack is now fine grained locked

    IPv6, IPSec and FAST IPSec work is currently moving forward



Kame, IPv6 and IPSec

    March 2006 the KAME Project Completed

    Most code moved into FreeBSD and NetBSD

    This code now belongs to each project and will no longer be actively maintained by the KAME project

    Several KAME members are also FreeBSD committers

        Umemoto (ume@)

        Suzuki (suz@)

    Several FreeBSD committers are now working to clean up and move the code forward



IPSec vs. FAST_IPSEC

    KAME IPSec and FAST_IPSEC are incompatible

    FAST_IPSEC does not have support for v6

    Currently working to make the following matrix possible

        FAST_IPSEC

        KAME IPv6 and IPSec

        KAME IPv6 and FAST_IPSEC

    Code is currently only available in PerForce and is unstable



Stream Control Transmission Protocol

    SCTP is a new transport protocol

    Often used in audio and video streams

    Can drop packets or not

    Keeps sequencing

    There are ports to several BSD operating systems

        FreeBSD

        NetBSD

        OpenBSD

        Mac OS X

    FreeBSD is working with the SCTP team to bring in their code



Questions?

在这期间，我就一些大家所关心的问题和George做了简单的交流，比如：如何成为优秀的程序员？如何成为FreeBSD committer等。同时也问了一些自己关心的问题，比如：Yahoo的程序员的桌面是什么操作系统？等。George都作了耐心、坦诚的解答。

如下是此次活动的一些照片：
http://www.billxu.com/friend/gnn/PICT0038.JPGNeville Neil畅谈FreeBSD" />

George刚到SINA，就开始帮Delphij解决FreeBSD jail的问题。;-)

http://www.billxu.com/friend/gnn/PICT0039.JPGNeville Neil畅谈FreeBSD" />

讨论问题。

http://www.billxu.com/friend/gnn/PICT0049.JPGNeville Neil畅谈FreeBSD" />

Delphij小朋友正在演讲

http://www.billxu.com/friend/gnn/PICT0054.JPGNeville Neil畅谈FreeBSD" />

George正在准备自己的讲稿

http://www.billxu.com/friend/gnn/PICT0067.JPGNeville Neil畅谈FreeBSD" />

阅读<<The Design and Implementation of the FreeBSD Operating System>>中文版

http://www.billxu.com/friend/gnn/PICT0068.JPGNeville Neil畅谈FreeBSD" />

给粉丝们签名

http://www.billxu.com/friend/gnn/PICT0083.JPGNeville Neil畅谈FreeBSD" />

一行人在“亢龙太子“共进晚餐