DEVOPSdigest

Among the industry segments contributing to climate change, Information and Communications Technology (ICT) represents over 10% of the total energy demand and generates about 2% of global CO2 emissions(link is external). The bulk of ICT's electricity demand comes from operating data centers. By 2030, their electricity demand is likely to grow 15 times or more(link is external) despite their use of energy-efficient technology, suggest studies2.

The increase in demand for data center resources, and the resulting increased in carbon footprint, is driven largely by software development across technology trends in enterprise IT, viz., big data, AI/ML, blockchain, crypto, and IoT. Organizations can develop and use software to reduce their carbon footprint, as outlined by the Green Software(link is external) Foundation. Enterprise IT teams can adopt the principles of green software engineering(link is external) in their journey to reach sustainability goals. DevOps practices are key enablers for them to improve carbon awareness and carbon-aware automation. Here's how DevOps teams can contribute to meeting sustainability goals.

1. Publish resource usage metrics for all CI/CD pipeline processes

Classical performance metrics are good proxies to get the relative energy consumption of CI/CD processes. Observability and application performance monitoring tools can collate these metrics which can then be published on DevOps dashboards.

2. Combine “change failure rate” with resource usage metrics

This helps us understand the wasted energy due to the failed CI/CD processes and provide resolutions. For example, a pipeline with a failure rate of 50% may have negligible energy consumption compared to one with only a 5% failure rate but more wasted energy. In such a case, the reduction of the latter should be a priority.

3. Incorporate specialized carbon-aware metrics

Cloud platforms such as AWS, Google Cloud, and Azure already provide native tools to report the carbon footprint of the resources used. For other environments, we can incorporate Carbon-Aware SDK(link is external) to measure the carbon footprint by process, location, and time of the day. Such insights optimize the combination of the greenest energy sources, at the greenest location, and at the greenest time.

4. Eliminate redundant tasks

The prevalent approach for CI / CD automation relies on automated workflows triggered by certain input events. When a developer checks in a code change, it triggers a pipeline process to build, deploy and automatically test the change through multiple test environments. Oftentimes, the code changes are limited to a few files, but the build and test process triggers the compilation and testing of large monolithic components involving hundreds of unchanged files. DevOps teams should identify such redundancies and optimize the workflows to minimize wasteful computations.

5. Remove unused applications, and ROT data

It is quite common to find old unused applications running on servers or to find ROT (Redundant, Obsolete, and Trivial) data being stored on servers. DevOps teams can identify unused applications, delete redundant storage resources, and set retention policies to automatically delete obsolete data.

6. Optimize network traffic

When software components (services) communicate with other components (services) external to their deployment zones, it results in a higher carbon footprint due to increased consumption of data center resources. DevOps teams can ensure that storage and compute resources are deployed within the same availability zone or use edge-computing / fog-computing architecture patterns to reduce latency and network traffic.

7. Optimize utilization for servers and storage units

Low utilization levels of resource units imply wasted energy for unused resources. For example, two servers with 20% utilization will consume more electricity and have more carbon footprint than a single server with 40% utilization. However, a utilization level of 100% will diminish the ability to scale. DevOps teams can set up low and high watermark levels for server and storage utilization levels and periodically right-size the servers to maintain utilization levels between the low and high watermarks.

8. Carbon-aware scheduling of jobs

Computing resources have periods of peak demand and low demand. It is possible to delay the execution of some non-critical jobs so that the peak demand for computing resources evens out. Further, DevOps teams can use carbon-aware SDK (or a similar tool) to determine the best time and location to execute jobs to minimize the carbon footprint within a specified time window.

The goal of DevOps, which combines developers and operations, is to increase the pace, regularity, and dependability of software development, testing, release, and operations. With the integration of carbon-aware standards and green software principles, DevOps will be an important enabler for achieving organizational sustainability goals.