Things to come

In a thread about booting media, Matt Dillon noted he was going to:

  • Look at Jeff Hsu’s TCP thread code
  • implement variant symlinks
  • start VFS messaging and environments

VFS will make a number of other things – especially a new port system – possible.

Flames bad, info good

On the freebsd-hackers mailing list, a slight flamewar erupted over discussion of checkpointing code from DragonFly. Amidst the dumbness that normally ensues in a flamewar, there’s some interesting descriptions on what work has been done/will be done on DragonFly. Check out the archive, mostly in the “FreeBSD mail list etiquette” thread. Matt Dillon’s posts here, here, and here are all info-packed.

ATAng discussion

Kip Macy brought up the idea of moving FreeBSD’s ataNG into DragonFly; the consensus so far is to bring it in separately from the existing ata support, since ataNG’s not yet completely stable.

Routing reading

Jeroen Ruigrok posted a whole pile of links to routing information for anyone wanting to work on it:

Basics:

TCP Vegas: End to End Congestion Avoidance on a Global Internet
http://citeseer.nj.nec.com/brakmo95tcp.html

Evaluation of TCP Vegas: Emulation and Experiment
http://citeseer.nj.nec.com/ahn95evaluation.html

TCP and Successive Fast Retransmits
http://citeseer.nj.nec.com/floyd95tcp.html

Congestion Avoidance and Control
http://citeseer.nj.nec.com/jacobson88congestion.html

Performance Problems in BSD4.4 TCP
http://citeseer.nj.nec.com/brakmo95performance.html

Comparison of Tahoe, Reno, and SACK
http://citeseer.nj.nec.com/fall95comparisons.html

TCP Vegas: New Techniques for Congestion Detection and Avoidance
http://citeseer.nj.nec.com/brakmo94tcp.html

A Tree-based Packet Routing Table for Berkeley Unix
http://www.cs.berkeley.edu/~sklower/routing.ps

Newer:

TCP Vegas Revisited
http://citeseer.nj.nec.com/hengartner00tcp.html

Analysis on TCP Vegas and TCP Reno
http://citeseer.nj.nec.com/hellal00analysis.html

Scalable Timers for Soft State Protocols
http://citeseer.nj.nec.com/48810.html

End-to-End Internet Packet Dynamics
http://citeseer.nj.nec.com/paxson97endtoend.html

End-to-End Routing Behavior in the Internet
http://citeseer.nj.nec.com/3573.html

Routing with a Clue
http://citeseer.nj.nec.com/afek99routing.html

IP Lookups using Multiway and Multicolumn Search
http://citeseer.nj.nec.com/lampson98ip.html

Fast and Scalable Layer Four Switching
http://citeseer.nj.nec.com/srinivasan98fast.html

High-Speed Policy-based Packet Forwarding Using Efficient
Multi-dimensional Range Matching
http://citeseer.nj.nec.com/lakshman98highspeed.html

Fast Address Lookups using Controlled Prefix Expansion
http://citeseer.nj.nec.com/srinivasan99fast.html

Checkpointing is in

Kip Macy’s checkpointing code has been committed; I’m pasting Matt Dillon’s post about it as there’s a lot of issues to consider.

For those of you late to the party, checkpointing allows you to “freeze” a copy of an application so that, in theory, you can restore the program to that running state at a later point in time. Useful, for instance, if you have a program that takes a long time to complete and you don’t want to have to restart from the beginning if there’s an interruption.
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