How much traffic can Memcached provide? What should I do if I need to expand the capacity?

Memcached is an in-memory key-value store designed for high-performance caching. Its traffic capacity depends on factors like server hardware (CPU, RAM, network), data access patterns, and cluster configuration. A single Memcached instance can typically handle tens of thousands of requests per second (QPS) under optimal conditions, with throughput scaling linearly as you add more nodes.

For example, if you're running Memcached on a server with 32GB RAM and a fast network interface, it might support ~50K QPS for small-value (e.g., 1KB) operations. However, performance degrades if the dataset exceeds available RAM or if network latency increases.

If you need to expand capacity:

1. Scale Horizontally: Add more Memcached servers to distribute the load. Use consistent hashing (e.g., libketama) to ensure keys are evenly distributed across nodes.
2. Optimize Data Size: Store smaller values (e.g., <1MB) to maximize RAM utilization. Compress large data before caching.
3. Use a Managed Service: For easier scaling, consider Tencent Cloud's TencentDB for Memcached, which automates node management, scaling, and monitoring. It supports auto-failover and integrates with other Tencent Cloud services like CLB (Load Balancer) for traffic distribution.

Example: If your app's cache traffic grows from 100K to 500K QPS, you can deploy a TencentDB for Memcached cluster with 10 nodes (each handling ~50K QPS) and let the service handle load balancing and scaling.