High-Performance TCP Server

Linux C++17 main/sub-reactor architecture — Epoll ET + memory pool + connection pool heartbeat + half/sticky packet handling.

What it solves

Understand the core techniques of Linux high-concurrency network programming: the reactor pattern, epoll edge-triggered I/O, memory pools, and packet fragmentation/assembly. Supports 100k+ concurrent connections — a solid reference and project foundation for learning C++ network programming.

Tech stack

C++17 · CMake · Linux Epoll ET · main/sub reactor · custom memory pool / thread pool

Features

• Main/sub reactor: main thread accepts connections, IO thread pool handles reads/writes
• Epoll edge-triggered: works with non-blocking IO
• Memory pool: pre-allocated fixed-size blocks, O(1) allocation
• Connection pool: heartbeat timeout detection, max connection limit
• Half/sticky packet handling: three strategies — line-based, fixed-length, and custom delimiters
• Graceful shutdown: eventfd interrupts all epoll_wait calls

Benchmark

Measured with the custom TitanBench tool (local WSL, 500 concurrent / 8 threads / 30 s):

Metric	Value
QPS	64,756 ~ 70,000+
Average latency	2.42 μs
P99 latency	7.00 μs
Success rate	100%

Usage

./build.sh
./build/bin/tcp_server -p 9999

# Test
nc 127.0.0.1 9999