GitHub Availability Report: August 2021

In August, GitHub experienced two significant incidents affecting various services, including Git operations and GitHub Actions, highlighting challenges with database and microservice management. On August 10, a MySQL database primary entered a degraded state due to a poorly performing query and application retry logic, affecting services requiring write access and leading to a prolonged outage. This incident prompted discussions on improving incident reporting and post-incident analysis to enhance service reliability. Later, on the same day, an unrelated incident during maintenance of the Actions service caused a high error rate due to a bad service record in the microservices architecture, disrupting workflow runs. The mitigation involved removing the faulty record, and GitHub has since prioritized changes to improve service discovery processes and enhance visibility across microservices. GitHub emphasizes ongoing efforts to refine their incident response and maintain user trust, encouraging users to follow updates on their status page and blog.