How we reduced peak memory and CPU usage of the product configuration management SDK

Summary

GrabX’s product configuration SDK used substantial memory and CPU because every client downloaded, decoded, and loaded a single JSON file containing configurations for all services, even when it needed only a small subset. The design also regenerated and fetched complete files every minute, while decoding a file larger than 100 MB could starve request handling and increase P99 latency. The proposed redesign partitions data by service, stores each configuration in its own JSON file and S3 prefix, and adds service-level changelogs so SDKs subscribe only to required services and apply targeted updates. Benchmarking across varied configuration sizes found potential reductions of up to 70% in memory utilisation and more than 50% in maximum CPU utilisation. Further work is planned to reduce SDK initialisation time.

Takeaways

1. 1

   The existing SDK loaded all service configurations even though 98% of client services needed less than 1% of the total configuration data.

2. 2

   Service-level changelogs identify configurations created or updated in each version, enabling targeted client-side updates instead of complete file reloads.

3. 3

   Benchmarking indicated potential memory reductions of up to 70% and maximum CPU utilisation decreases of more than 50% across varied configuration data sizes.