Linux Conference Australia (Day 4)

Linux TCP Developments and Kernel Developer Social Interactions

  • Deliberately redesigned the TCP congestion control code to make it easy for people to use the Linux Kernel to test new algorithms.
  • DCCP is UDP with congestion control. Linux is has the first decent shipping implementation.
  • Sun's new Niagra chip is designed to make performance in aggregate better. David Miller is working on a Linux port to Niagra.
  • Code is written by people, if you're a dick, the people will ignore your code. The trick is to make people want to work with you.

FAI - Fully Automatic Installer

  • Has a nice system for assigning machines to classes with simple scripts. The classes then control how the machine is built and what packages are installed and how they are configured.
  • Should work just fine with Ubuntu, the only trick is that you have to use the Ubuntu version of debootstrap to build the FAI NFS root.
  • Just got it working with Mandriva and expect to be able to support most RPM distro's soon.

Linux for Broadband Rural Wireless, The CRCnet Experience

  • New satellite technology is looking promising for rural areas.
  • Rural networks should be community focused, this is especially helpful with getting access to sites for gear and dealing with any political issues.
  • Many good repeater locations don't have power. Solar becomes the best solution, so low power devices are critical.
  • Started with Advantech SBC, but they were finicky about power. Moved to Soekris boards and they have been much more reliable.
  • Using Trango / Proxim Quickbridge 20 for backhaul links.
  • JFFS is a journaled flash filesystem, CRC didn't use it, maybe they should have.
  • Run Debian on their embedded boxes, but rebuild all packages using sbuilder to strip out unnecessary features and documentation to keep package size as small as possible.
  • Soekris supports PXE booting, so they have a build server for any box on the network.
  • Configuration files are stored on a central server to aide in initial build and disaster recovery.
  • Use Quagga for routing and SRG and AMP for monitoring.
  • Built an impressive sounding configuration management which manages all dependancies between nodes.
  • Keeping sites under three meters high keeps you out of a whole bunch of resource consent issues.

Bazaar-ng: Friendly, Distributed Version Control

  • Disconnected operation was originally perceived as the primary benefit, but the main advantage is actually the much better branching and merging tools.
  • Every repository is a backup and holds the entire history of the repository.
  • Uses the Weave algorithm to store delta's (originally used in SCCS and BitKeeper).
  • config-manager can be used to build a tree from separate source modules (useful for server config files?)

Concurrency Control in RDBMS

  • MySQL cluster is optimized for certain types of queries, make sure it suits what you want to do.
  • In version 5.1 you can store data on disk with MySQL cluster.
  • Archive backend compresses data as it goes to disk. Can only SELECT / INSERT, you can't do UPDATEs. All SELECTs happen across the entire table, it was written for Yahoo! for archiving all of their logs.
  • The CSV backend can be used to copy files into or out of MySQL. Might be useful for moving data between Filemaker and MySQL?
  • MyISM doesn't lock on INSERTs if it's appending to the table on the filesystem. This is useful if you are dumping logs into MySQL from many sources. If you delete records then beware that the wholes will get filled first and it will lock until there are no more holes.