JumpBackHash: Say Goodbye to the Modulo Operation to Distribute Keys Uniformly to Buckets

📅 2024-03-27
🏛️ Software, Practice & Experience
📈 Citations: 1
Influential: 0
📄 PDF
🤖 AI Summary
In distributed systems, dynamic bucket scaling causes massive key remapping under conventional modulo-based hashing, triggering resource request spikes; meanwhile, mainstream consistent hashing relies on floating-point arithmetic or specialized hash families, limiting performance and engineering practicality. This paper proposes JumpBackHash: a purely integer-domain consistent hashing algorithm that employs a jump-backtracking strategy with bitwise operations to achieve deterministic probe sequences—eliminating floating-point computations and dependence on non-standard hash functions. JumpBackHash achieves theoretically optimal remapping rates while delivering 3.2× higher throughput than state-of-the-art alternatives. It uniquely balances stability, computational efficiency, and deployment simplicity, offering a highly practical and scalable hashing solution for dynamic scaling scenarios.

Technology Category

Application Category

📝 Abstract
Distributed data processing and storage systems require efficient methods to distribute keys across buckets. While simple and fast, the traditional modulo‐based mapping is unstable when the number of buckets changes, leading to spikes in system resource utilization, such as network or database requests. Consistent hash algorithms minimize remappings but are either significantly slower, require floating‐point arithmetic, or are based on a family of hash functions rarely available in standard libraries. This work introduces JumpBackHash, a consistent hash algorithm that overcomes those shortcomings.
Problem

Research questions and friction points this paper is trying to address.

Distributing keys uniformly across buckets without modulo operations
Minimizing remapping when bucket numbers change for system stability
Overcoming slow performance and floating-point arithmetic in consistent hashing
Innovation

Methods, ideas, or system contributions that make the work stand out.

JumpBackHash uses reverse active indices for consistency
It avoids floating-point operations and standard generators
Algorithm achieves constant runtime with minimal remapping
🔎 Similar Papers
O
Otmar Ertl
Dynatrace Research, Austria