When Caches Bite Back: Stampedes, Avalanches, and Penetration
The cache that made your system fast can also take it down. Three failure modes, the 2010 Facebook outage, and how to defend against each. Part 6 of 8.
#system-design
8 entries
Every Layer Is a Cache: From Browser to CDN to Database
A request can stop at six different caches before it reaches your database. Here's how HTTP caching works, and how it goes wrong. Part 5 of 8.
Cache Invalidation: Why It's Really One of the Two Hard Problems
TTLs, deletes, versions, and the race condition that leaves stale data in your cache forever. Part 4 of the 8-part caching series.
Who Gets Evicted? LRU, LFU, and the Algorithms Inside Real Caches
Caches are always full. How eviction policies decide what to throw out, why LRU gets fooled by scans, and how to build an LRU yourself. Part 3 of 8.
Cache-Aside, Write-Through, Write-Behind: How Your Cache Talks to Your Database
Five ways to wire a cache to a database, what each one costs you, and how to pick. Part 2 of the 8-part caching series.
Caching 101: The 100x Trick Behind Every Fast System
What a cache actually is, why it works, and the one formula that tells you if yours is helping. Part 1 of an 8-part series on caching.
Transactions: The Art of All or Nothing
A deep dive into database transactions - the beauty and the nightmare.
Re-use or Re-invent: It’s Fuzzier Than You Think
A foundational mental model for deciding when to reuse existing architectures versus reinventing them — guiding objective engineering decisions.