Libreactor - Extreme HTTP Performance Server

Optimized HTTP server based on libreactor with extreme performance.

🚀 Quick Start

# Compile with optimizations
./compile.sh

# Start the server
./run-optimized.sh

# Check status
./status.sh

# Stop the server
./stop.sh

📊 Benchmarking

# Quick test
wrk -t8 -c512 -d10s http://localhost:2342/plaintext

# Full benchmark
/var/www/benchmark-libreactor.sh

⚡ Performance Optimizations

Application Level Code

• SO_REUSEPORT + BPF filter - connection distribution across CPUs
• Busy Poll (SO_BUSY_POLL) - low latency for network operations
• TCP_NODELAY - disabling Nagle algorithm
• SO_KEEPALIVE = 0 - disabling keepalive for performance
• Multi-process architecture - process per CPU with CPU pinning

Compilation

• -O3 -march=native -flto - maximum optimizations
• -DNDEBUG -fomit-frame-pointer -funroll-loops - additional optimizations

System Level

• Kernel parameters: nospectre_v1 nospectre_v2 pti=off mds=off tsx_async_abort=off
• Network sysctl: 16MB buffers, busy poll, TCP optimizations
• Nftables instead of iptables (minimal overhead)

📁 Project Structure

/var/www/rads/
├── build/                     # Build directory (generated during compilation)
├── src/                       # Source code
│   ├── domain/                # HTTP domain logic
│   │   ├── http_response.c
│   │   └── http_server.c
│   ├── include/               # Header files
│   │   ├── compat/           # Compatibility headers
│   │   │   ├── dynamic.h
│   │   │   └── reactor.h
│   │   ├── domain/           # Domain headers
│   │   │   ├── http_response.h
│   │   │   └── http_server.h
│   │   ├── infrastructure/   # Infrastructure headers
│   │   │   └── server_infrastructure.h
│   │   └── platform/         # Platform headers
│   │       ├── log.h
│   │       ├── process.h
│   │       ├── signals.h
│   │       ├── socket.h
│   │       └── system.h
│   ├── infrastructure/        # Server infrastructure
│   │   └── server_infrastructure.c
│   ├── main/                  # Main application files
│   │   ├── libreactor-server.c
│   │   └── libreactor.c
│   └── platform/              # Platform utilities
│       ├── log.c
│       ├── process.c
│       ├── signals.c
│       ├── socket.c
│       └── system.c
├── compile.sh                 # Compilation with optimizations
├── run-optimized.sh          # Start with CPU pinning
├── stop.sh                   # Stop and cleanup
├── status.sh                 # Check status
├── Makefile                  # Alternative makefile
├── drop_changes.sh           # Git changes reset
├── fast_commits.sh           # Fast commits
├── switch_branch.sh          # Branch switching
├── git-init.sh               # Git repo initialization
├── libreactor-server.dockerfile # Dockerfile for server
├── libreactor.dockerfile     # Dockerfile for libreactor
└── README.md                 # This file

🎯 Performance

• 44k+ req/sec on plaintext (3 CPUs, KVM virtualization, local test)
• 41k+ req/sec on JSON responses (3 CPUs, KVM virtualization)
• CPU spent on sendto() (useful work)
• Minimal locks and context switches

🔧 API

Endpoints

• GET /plaintext - returns "Hello, World!"
• GET /json - returns {"message":"Hello, World!"}

Example Request

curl http://localhost:2342/plaintext
# Hello, World!

curl http://localhost:2342/json
# {"message":"Hello, World!"}

🛠️ Development

Recompilation

make clean
make CFLAGS="-O3 -march=native -flto -DNDEBUG" libreactor-server

Debug Build

make CFLAGS="-O0 -g" libreactor-server

📈 Monitoring

CPU Profiling

perf record -F 99 -g -p $(pgrep libreactor-server | head -1) -o perf.data -- sleep 10
perf report -i perf.data

System Calls

bpftrace -e 'tracepoint:syscalls:sys_enter_sendto { @[comm] = count(); } interval:s:1 { print(@); clear(@); }'

🔗 Links

• Libreactor
• Extreme HTTP Performance Tuning
• SO_REUSEPORT