Redis isn’t just a fancy cache – it’s a grenade. Pull the wrong pin (ahem, maxmemory), and BOOM 💥
maxmemory & Eviction Policies: Stop Redis From Ghosting Your Data
The Problem: Redis doesn’t magically clean up. Set maxmemory too high, and it’ll eat your RAM like a Cookie Monster. Set it too low, and it’ll evict data mid-transaction.
The Fix:
First: set the max memory limit that Redis can't exceed out of your server resources
Use the eviction strategy option that meets your needs. Example:
volatile-lru for mixed workloads (bye-bye, least-recently-used expired keys).
allkeys-lfu if you’re a data hoarder (prioritize frequently used keys, even if they’re immortal).
All options:
Pro Tip: Test evictions before your app trends on Hacker News.
Lua Scripts: Your Atomic Weapon Against Race Conditions
Why It Matters: 5 clients updating the same key? Chaos. Lua scripts execute atomically.
Later, you can pull your data from Redis into whatever DB you use for consistency.
Retries, Timeouts & Processors (Yes, That’s a Word Now)
- Retries: 3 retries with exponential backoff. More? You’re just DDoSing yourself.
- Timeouts: connect_timeout: 5s, read_timeout: 2s. Your app isn’t a hostage negotiator.
- Processors: Redis is single-threaded. If your CPU cores are screaming, shard or migrate heavy ops to background workers.
Redis isn’t ‘set it and forget it’ – it’s ‘set it, tweak it, and make your on-call rotations boring again’. Try one tip today, and thank me when you’re sleeping through deploy windows.
Comment your worst Redis horror story – bonus points for plot twists involving FLUSHALL
Thanks for reading
