Do I need Redis or Memcached?
Not immediately, but you will want it as you grow. Benecaster caches your podcast feeds by tier — 1,000 subscribers across 4 tiers produces 4 cached documents, not 1,000. With Redis or Memcached, those cache reads happen in memory with no database query at all.
Without an object cache, feed requests still work but every request involves a database query — more load on your server. Under 500 subscribers most hosts handle this without issue. Above 500, the database load from concurrent feed polls — particularly around episode releases — can noticeably affect site performance.
Most managed WordPress hosts (WP Engine, Kinsta, Cloudways) offer Redis as a one-click feature. LiteSpeed-based hosts (A2 Hosting, Namecheap) can use LiteSpeed Cache’s built-in object cache. No Benecaster configuration is needed — it uses the standard WordPress object cache API and picks up any compatible backend automatically.