https://nalar.dev/tags/consistent-hashing/ Recent content in Consistent Hashing on Nalar Hugo en-us Sun, 20 Sep 2026 00:00:00 +0000 https://nalar.dev/consistent-hashing-limits-key-movement-when-nodes-change/ Sun, 20 Sep 2026 00:00:00 +0000 https://nalar.dev/consistent-hashing-limits-key-movement-when-nodes-change/ <p>Partitioning by <code>hash(key) % N</code> is simple when the node count stays fixed. The arithmetic becomes disruptive when <code>N</code> changes. Moving from four nodes to five changes the divisor, so many keys select a different remainder even though only one node joined.</p> <p>Consistent hashing changes the mapping. Keys and nodes are placed in the same circular hash space. A key belongs to the first node encountered in a chosen direction around the ring. Adding or removing a node changes ownership only for ranges adjacent to that membership change.</p>