Making an eBPF based LoadBalancer from scratch

TODOs

• Read in detail about SmartNICs (Smart Network Interface Cards).

CONCEPTS

• DMA Buffers : The dma-buf subsystem provides the framework for sharing buffers for hardware (DMA) access across multiple device drivers and subsystems, and for synchronizing asynchronous hardware access. As an example, it is used extensively by the DRM subsystem to exchange buffers between processes, contexts, library APIs within the same process, and also to exchange buffers with other subsystems such as V4L2.

• inode : https://en.wikipedia.org/wiki/Inode

• Everything You Need To Know About Hairpinning and Traffic Backhauling

• Pinning

• north-south vs east-west traffic

REFERENCES

• Mentorship Session: An Introduction to Linux Tracing and its Concepts
• A Gentle Introduction to BPF using bpftrace
• BPF With C
• eBPF with GO: A Gentle Introduction
• A Moderate Introduction to BPF programming with Rust
• Tutorial: Developing Portable eBPF Applications Workshop - Lin Sun, solo.io

  How do we measure the impact of eBPF programs on the Kernel? According to the workshop author, the overhead of the eBPF program is around 1-2% of the CPU, since it's very lightweight.

• Kernel Analysis Using eBPF - Daniel Thompson, Linaro
• BPF and XDP Reference Guide

  In here, you'll get to know about the architecture of eBPF, what's BPFFS and XDP and tc (traffic control).

Useful tools and libraries

• bcc
• libbpf
• bpftool
• bpftrace
• Bumbleblee
• syscall snoopers
• bpf-helpers
• bpfman