Mahimahi

What Mahimahi is

Mahimahi is a free set of Linux tools for measuring and emulating web performance. Its tools model propagation delay, link rates, and stochastic packet loss; LinkShell also offers DropTail, DropHead, and CoDel queueing disciplines. Tools can be nested to combine network effects. RecordShell saves real HTTP content to disk for later replay with ReplayShell, which mirrors a page’s server distribution locally and serves requests from real web servers. The project says the tools can run unmodified Chrome, Firefox, and Safari, as well as virtual machines and mobile-device emulators. Each tool starts a lightweight container, generally connected through a synthetic network device. The project provides Ubuntu installation instructions through an apt repository and documents building from source. Its listed free software plan costs nothing for Ubuntu 14.04 or higher. The public project repository identifies the license as GPL-3.0, and an automation API is available. The site also links a research paper presented at the 2015 USENIX Annual Technical Conference.

Who it suits

Mahimahi is intended for browser developers, website authors, and network protocol designers examining web behavior under controlled network conditions. It suits Linux users who want to record and replay web traffic or combine network effects.

Getting started

1. Use the project’s Ubuntu installation instructions and apt repository.
2. Alternatively, follow the project’s instructions to build from source.
3. Run Mahimahi tools in their lightweight containers.
4. Use RecordShell to save HTTP content and ReplayShell to replay it.

Verdict

Mahimahi brings traffic recording, replay, and network emulation into a composable Linux toolset. Its fit depends on your Linux environment and the network conditions you need to model.