Linux

Table of Contents

• Introduction
• Packet Processing
• Packet Handling
• Traffic Control
• NAPI
• Miscellaneous

Introduction

A collection of Linux internals, mostly geared towards Computer Networking.

C programming resources

Packet Processing

• Queueing in the Linux Network Stack
• Kernel-bypass techniques for high-speed network packet processing
• Illustrated Guide to Monitoring and Tuning the Linux Networking Stack: Receiving Data
• How Linux processes your network packet
• SYN packet handling in the wild
• Listening to Networks
• The Network Packet’s Diary: A Kernel Journey
• Path of a Packet in the Linux Kernel Stack
• New API (NAPI)

Packet Handling

• Socket
  • socket(7) describes the Linux networking socket layer user interface and socket(2) creates an endpoint for communication and returns a file descriptor that refers to that endpoint.
    • What the numbers 2 and 7 mean: The Linux man-pages project (check ‘intro’ pages)
  • Socket/Address family (AF_INET, AF_INET6, etc.)
  • Socket type (SOCK_STREAM, SOCK_DGRAM, etc.)
• bind(2)
• recvmsg(2)
  • System calls: syscalls(2)
• sysctl(8) system administration command to configure kernel parameters at runtime.
  • Linux sysctl command

Traffic Control

• tc(8) stands for ‘Traffic Control’ and it shows and manipulates traffic control settings.
  • Traffic Control HOWTO

NAPI

• NAPI: New Application Programming Interface
• NAPI is a part of the packet processing framework of Linux and provides interrupt mitigation and packet throttling to improve the performance of high-speed networking.
• New API (NAPI)
• What are the advantages NAPI before the IRQ Coalesce?

Miscellaneous

• Linux networking references
• Scaling in the Linux Networking Stack (RSS, RPS, RFS, etc.)
• Networking in a Linux Container in Docker