# session-replay-tools/tcpcopy

An online request replication and TCP stream replay tool, ideal for real testing, performance testing, stability testing, stress testing, load testing, smoke testing, and more.

Repository: https://github.com/session-replay-tools/tcpcopy
Canonical: https://ross.abutalabs.com/products/tcpcopy
Homepage: http://session-replay-tools.github.io/tcpcopy/
Language: C
License: NOASSERTION
License Family: other
Topics: testing-tools, testing, replay-mysql-traffic, replay-http-traffic, replay, stress-testing, load-testing, smoke-testing, real-testing, apache, mysql, nginx, performance-improvements, performance-testing, simulation, stability, tcp, tcp-server, performance, redis
Last push: 2025-06-18T04:34:08+00:00

## Health v2 (maintenance only)
Score: 35/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 27, release rhythm 8, longevity 100
- inputs: {"age_days": 5437, "days_push": 441, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 4675, forks 1025 (observed 2026-08-28T04:08:56.689191+00:00)

## What it is
TCPCopy is a TCP stream replay tool that captures live production traffic and replicates it against a test server. It enables realistic stress, performance, stability, and regression testing by generating workloads that mirror production request diversity and network latency.

## Use cases
- replay production HTTP traffic to a staging server
- stress test nginx or mysql with real-world traffic
- validate stability of a new system before launch
- run regression testing with live traffic patterns
- compare performance across server versions or configurations
- pre-warm caches with replicated production requests

## When to choose
- you need realistic production-like workloads instead of synthetic load generators
- you want to replay live TCP traffic (HTTP, MySQL, Redis, etc.) with minimal production impact
- you need distributed stress testing across multiple servers

## When to avoid
- you only need simple synthetic load testing without real traffic
- your environment cannot run raw-socket packet capture or route response packets to an assistant server
- you need a cross-platform GUI tool rather than a Linux C command-line utility

## Facets
- artifact type: cli-tool
- maturity: stable
- function: testing, benchmarking, simulation, networking
- domain: testing, performance, networking, developer-tools
- platform: cli
- tags: traffic-replay, tcp, stress-testing, load-testing, live-testing, c, linux

## Member repositories
- session-replay-tools/tcpcopy (main) score 35

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:08:56.689191+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T18:19:21.922668+00:00, confidence not recorded.
  - readme: https://github.com/session-replay-tools/tcpcopy (fetched 2026-08-28T04:08:56.689191+00:00, sha 0b57a309bff6)
  - homepage: http://session-replay-tools.github.io/tcpcopy/ (fetched 2026-08-29T09:03:34.926444+00:00, sha 12a0c43cdb67)
- Data as of 2026-08-30T08:39:29.467469+00:00.