hashdistributed-computingconsistent-hashing

Rendezvous vs consistent hashing


I read on Wikipedia:

Unlike consistent hashing, HRW (Highest Random Weight, aka Rendezvous Hashing) requires no precomputing or storage of tokens.

Why?

My understanding is that:

so, if anything, it looks to me that in consistent hashing, one could choose to pre-compute and pre-store h(Sj)s but you are not required to do so. In other words, consistent hashing provides that flexibility whereas HRW doesn't.

Am I wrong? If so why?

Here's a reference description of HRW from the same link:


Solution

  • You are correct. The fact that we can pre-compute and pre-store h(Sj) is rather an advantage for consistent hashing.

    Wikipedia states that the advantage for Rendezvous hashing is that its conceptually simpler to understand and implement (although I dont agree personally).

    And it mentions one more advantage:

    Rendezvous hashing also has the great advantage that it provides simple solutions to other important problems, such as distributed k-agreement.