These projects look really solid - they are drop-in replacements for Redis and should offer the most closely matched performance without the need to keep everything in RAM:
SSDB - A fast NoSQL database, an alternative to Redis - GitHub - ideawu/ssdb: SSDB - A fast NoSQL database, an alternative to Redis
faviconGitHub (github.com)
https://github.com/ledisdb/ledisdb
https://github.com/Tencent/Tendis
https://github.com/KvrocksLabs/kvrocks
Has anyone tried?