When should we think about using a global caching strategy?

hey folks, weve been seeing some latency spikes in our core services, especially with our international user base. Were already using some local Redis instances for session data, but im wondering if its time to think about a more centralized, potentially geo-distributed caching layer. What are your experiences with implementing global caches? What factors tipped the scales for you to go that route, and what were the biggest hurdles you faced? Are there specific patterns or technologies youd recommend investigating?