Abstract Algorithms

caching

3 articles across 3 sub-topics

System Design: Caching and Asynchronism

TLDR: Caching stores hot data in fast RAM so you skip slow database round-trips. Asynchronism moves slow tasks (email, video processing) off the critical path via message queues. Together, they turn a blocking, slow system into a responsive, scalable...

Mar 9, 2026•13 min read

Data Structures(1)

LLD for LRU Cache: Designing a High-Performance Cache

TLDR TLDR: An LRU (Least Recently Used) Cache evicts the item that hasn't been accessed the longest when it's full. The classic implementation combines a HashMap (O(1) lookup) with a Doubly Linked List (O(1) move-to-front) for overall O(1) get and p...

Mar 9, 2026•21 min read

Algorithms(1)

How Bloom Filters Work: The Probabilistic Set

TLDR TLDR: A Bloom Filter is a bit array + multiple hash functions that answers "Is X in the set?" in $O(1)$ constant space. It can return false positives (say "yes" when the answer is "no") but never false negatives (never says "no" when the answer...

Mar 9, 2026•14 min read