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Anish Ansari

Food,Code and Cloud Computing. You can support here :https://www.buymeacoffee.com/anishansari

12h ago

System Design Drill Day 2: Caching, TTLs and Cache Stampedes

A flash sale starts at noon. Half a minute in, the cache entry for the hottest product expires, every request for it misses Redis in the same instant, and all of them go straight to MySQL. At that poi

blog.anishansari.com.np8 min read

#redis #system-design #caching #laravel #interview-preparation

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Abhinav Sharma

Founder of Impact Gate. See who breaks before you change an API.

1h ago

The soft TTL with background refresh is the nicest answer here, the herd never forms because only one worker rebuilds while everyone else serves the stale copy. Picking TTLs per data type instead of one global value is also the part people usually skip.

Abhinav Sharma

Founder of Impact Gate. See who breaks before you change an API.

12h ago

The jitter point deserves more attention than it gets. If every key gets the same TTL, they were all written in the same deploy and will expire together, so the herd reforms on a schedule. Even 10 percent randomness spreads the misses out enough to matter.

Anish Ansari

Food,Code and Cloud Computing. You can support here :https://www.buymeacoffee.com/anishansari

8h ago

Thanks Abhinav, keys written in the same deploy expiring together is exactly how it bites in practice. A little jitter turns one big stampede into a trickle the database can handle.