How consistent hashing works

Place keys on servers, change membership and count ownership changes. Compare modulo placement with a clockwise hash ring and virtual positions.

When to use it

Assign cache keys across a changing fleet while reducing how many owners must change.

Explore the tradeoffs

Changing the divisor can move keys between existing servers too. Modulo placement is simple, but membership changes are disruptive.

Adding a ring owner changes only the ranges it takes over. Uneven token spacing can produce uneven ownership.

Virtual positions spread each physical server's ranges around the ring. More positions add metadata; they cannot split one extremely hot key.

Model boundaries

This is a placement model, not data migration or replication. The hash is deterministic and noncryptographic; small samples can still be uneven.