Creating a Virtuous Cycle in Performance Testing at MongoDB

TL;DR

This paper discusses enhancements to MongoDB's performance testing environment that create a virtuous cycle, leading to faster detection of regressions, better coverage, and continuous improvement of software performance.

Contribution

The paper introduces specific changes to MongoDB's performance testing system that improve coverage, accuracy, and speed, fostering a cycle of ongoing performance enhancement.

Findings

Improved detection of performance regressions

Enhanced testing coverage and accuracy

MongoDB's performance has become faster and more reliable

Abstract

It is important to detect changes in software performance during development in order to avoid performance decreasing release to release or dealing with costly delays at release time. Performance testing is part of the development process at MongoDB, and integrated into our continuous integration system. We describe a set of changes to that performance testing environment designed to improve testing effectiveness. These changes help improve coverage, provide faster and more accurate signaling for performance changes, and help us better understand the state of performance. In addition to each component performing better, we believe that we have created and exploited a virtuous cycle: performance test improvements drive impact, which drives more use, which drives further impact and investment in improvements. Overall, MongoDB is getting faster and we avoid shipping major performance regressions to our customers because of this infrastructure.