Infrastructure

At GitHub we recently revamped how we do DNS from the ground up. This included both how we interact with external DNS providers and how we serve records internally to…

Building robust systems involves designing for failure. As Site Reliability Engineers at GitHub, we’re always on the lookout for places where redundancy can help to mitigate problems, and today we’ll…

Historically, we have used Redis in two ways at GitHub: We used it as an LRU cache to conveniently store the results of expensive computations over data originally persisted in…

GitHub uses MySQL to store its metadata: Issues, Pull Requests, comments, organizations, notifications and so forth. While git repository data does not need MySQL to exist and persist, GitHub’s service…

Over the last year we’ve developed our new load balancer, called GLB (GitHub Load Balancer). Today, and over the next few weeks, we will be sharing the design and releasing its components as open source software.

Spokes is the replication system for the file servers where we store over 38 million Git repositories and over 36 million gists.It keeps at least three copies of every repository…

At GitHub we use MySQL as our main datastore. While repository data lies in git, metadata is stored in MySQL. This includes Issues, Pull Requests, Comments etc. We also auth…

At GitHub we place an emphasis on stability, availability, and performance. A large component of ensuring we excel in these areas is deploying services on bare-metal hardware. This allows us…

Last Friday we announced and performed a migration of all GitHub Pages to their own github.io domain. This was a long-planned migration, with the specific goal of mitigating phishing attacks…

Over the last month or so, we noticed steady week-over-week rises in overall MySQL query time. A poorly-performing database makes for a slow site and a slow site makes for…