# Siege — HTTP Load Testing and Benchmarking Utility

> Siege is a multi-threaded HTTP load testing tool that simulates concurrent users hitting a web server, providing throughput, response time, and availability metrics.

## Install

Save as a script file and run:

# Siege — HTTP Load Testing and Benchmarking Utility

## Quick Use
```bash
# Install
sudo apt install siege   # Debian/Ubuntu
brew install siege       # macOS
# Run a quick benchmark
siege -c 50 -t 30s https://example.com/
```

## Introduction
Siege is a command-line HTTP load testing tool designed to let developers and administrators measure web server performance under stress. It supports HTTP/1.1 and can test single URLs or lists of endpoints with configurable concurrency levels, making it a practical choice for quick capacity checks.

## What Siege Does
- Simulates concurrent users with configurable thread counts
- Supports HTTP and HTTPS with keep-alive connections
- Reads URL lists from files for multi-endpoint testing
- Reports transactions per second, response time, throughput, and availability
- Supports basic and digest authentication for protected endpoints

## Architecture Overview
Siege spawns a configurable number of threads, each simulating a user that sends HTTP requests in a loop. It uses libcurl under the hood for HTTP communication, supporting cookies, redirects, and TLS. Results are aggregated across all threads and presented as summary statistics after the test duration or request count is reached.

## Self-Hosting & Configuration
- Install via system package managers or compile from source with autotools
- Configure defaults in `~/.siege/siege.conf` for concurrency, timeout, and logging
- Set user-agent, connection timeout, and protocol version in the config file
- Use `-f urls.txt` to load a list of URLs for randomized testing
- Enable CSV logging with `--log` for post-analysis in spreadsheet tools

## Key Features
- Adjustable concurrency from 1 to thousands of simultaneous users
- Internet mode with random delays between requests for realistic simulation
- URL list support with GET and POST request methods
- Transaction logging for historical performance tracking
- Header and cookie support for authenticated endpoints

## Comparison with Similar Tools
- **wrk** — Higher performance with Lua scripting, but no built-in URL list support
- **Apache Bench (ab)** — Simpler tool, single URL only, no keep-alive in older versions
- **Vegeta** — Go-based constant-rate attacker with structured output
- **k6** — JavaScript-scripted load testing with cloud dashboards and checks

## FAQ
**Q: How many concurrent users can Siege handle?**
A: Siege can simulate thousands of concurrent users depending on system resources. Use the `-c` flag to set the count.

**Q: Can I test POST requests with Siege?**
A: Yes. Include POST data in the URL file using the format `https://example.com/api POST key=value` or use the `--content-type` flag.

**Q: Does Siege support HTTP/2?**
A: Siege primarily targets HTTP/1.1. For HTTP/2 testing, consider tools like h2load or k6.

**Q: How do I interpret the availability metric?**
A: Availability is the percentage of successful transactions (non-error HTTP responses) out of total attempted transactions.

## Sources
- https://github.com/JoeDog/siege
- https://www.joedog.org/siege-home/

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Source: https://tokrepo.com/en/workflows/asset-8dee99de
Author: Script Depot