Consistent Hashing
Visualize the hash ring, virtual nodes, and key distribution under topology change.
Nodes
4
Virtual nodes
48
Imbalance
64%
load spread (0% = perfectly even)
Keys moved
0
Per-node load
Node 062
Node 114
Node 227
Node 317
How this simulator works
A hash ring maps keys to nodes clockwise. Virtual nodes smooth the distribution; adding or removing a node only remaps a fraction of keys.
Why consistent hashing?
In a normal hash-mod-N scheme, adding a node reshuffles almost every key. Consistent hashing places nodes and keys on a ring, so a topology change only moves the keys that fall between the old and new positions.
The role of virtual nodes
- With one point per physical node, load is lumpy and small node counts are very unbalanced.
- Each node gets many virtual points on the ring, so its keys are spread out — variance drops sharply.
- More virtual nodes → smoother distribution, at the cost of a larger ring table.