Kernel and TC patches

The ADSL-optimizer Queues module is dependent on some kernel and TC/iproute2 patches.

Theory

The kernel and TC patch is a link layer overhead modeling patch, which accounts for the overhead on ADSL. This include accounting for the ATM / AAL5 cell alignment and the specific type of ADSL encapsulation overhead.
Chapter 5, describes the ADSL protocol stack, which concerns the ATM/AAL5 cell alignment and a description of the types of ADSL encapsulation. Section 5.2 provides an overview of the different encapsulation methods and their specific overhead.
Chapter 6, contains a description and evaluation of the link layer overhead modeling. Section 6.1.2 gives a description of the patch, which describes the shortcomings of the Linux Traffic Control implementation of the "rate table" lookup system (which is used by all the Token Bucket based schedulers) and how this is turned into an advantage when doing ATM cell alignment.

Patches

The patch consists of two parts a kernel and TC/iproute2 patch. The kernel patch is kept small, where the TC/iproute2 patch is more intrusive.

Patches: Kernel

• Kernel overhead patch (2.4) against 2.4.29 (also works for 2.4.32) for HTB only.
• Kernel overhead patch (2.4) against 2.4.29 (also works for 2.4.32) for all Token Bucket based schedulers (HTB, CBQ, TBF and police). (Only tested thoroughly for the HTB scheduler)
• Kernel overhead patch (2.6) against 2.6.15.4 for HTB only.
• Kernel overhead patch (2.6) against 2.6.15.4 for all Token Bucket based schedulers (HTB, CBQ, TBF and police). (Only tested thoroughly for the HTB scheduler)

Patches: iproute2/tc

The TC/iproute2 patch modifies the rate tables to account for the ADSL/ATM link layer / cell alignment.
Notice: The TC patch is against the new version of the iproute2 utility.

• TC/iproute2 patch against iproute 2.6.9.
• TC/iproute2 patch against iproute 2.6.15-060110.
• Patched TC binary iproute 2.6.9 static linked.
• Patched TC binary iproute 2.6.11 static linked.
• Patched TC binary for kernel 2.6.24.