1 0 O ct 2 01 3 On the Insertion Time of Cuckoo Hashing ∗
نویسندگان
چکیده
Cuckoo hashing is an efficient technique for creating large hash tables with high space utilization and guaranteed constant access times. There, each item can be placed in a location given by any one out of k different hash functions. In this paper we investigate the random walk heuristic for inserting in an online fashion new items into the hash table. Provided that k ≥ 3 and that the number of items in the table is below (but arbitrarily close) to the theoretically achievable load threshold, we show a polylogarithmic bound for the maximum insertion time that holds with probability 1− o(1) as the size of the table grows large.
منابع مشابه
On the insertion time of random walk cuckoo hashing
Cuckoo Hashing is a hashing scheme invented by Pagh and Rodler [9]. It uses d ≥ 2 distinct hash functions to insert items into the has table. It has been an open question for some time as to the expected time for Random Walk Insertion to add items. We show that if the number of hash functions d = O(1) is sufficiently large, then the expected insertion time is O(1) per item.
متن کاملConstant Access Time ?
We generalize Cuckoo Hashing 23] to d-ary Cuckoo Hashing and show how this yields a simple hash table data structure that stores n elements in (1 +) n memory cells, for any constant > 0. Assuming uniform hashing, accessing or deleting table entries takes at most d = O(ln 1) probes and the expected amortized insertion time is constant. This is the rst dictionary that has worst case constant acce...
متن کاملOn risks of using a high performance hashing scheme with common universal classes
The contribution of this thesis is a mathematical analysis a high performance hashing scheme called cuckoo hashing when combined with two very simple and efficient classes of functions that we refer to as the multiplicative class and the linear class, respectively. We prove that cuckoo hashing tends to work badly with these classes. In order to show this, we investigate how the inner structure ...
متن کاملLecture 10 — March 20 , 2012
In the last lecture, we finished up talking about memory hierarchies and linked cache-oblivious data structures with geometric data structures. In this lecture we talk about different approaches to hashing. First, we talk about different hash functions and their properties, from basic universality to k-wise independence to a simple but effective hash function called simple tabulation. Then, we ...
متن کامل3.5-Way Cuckoo Hashing for the Price of 2-and-a-Bit
The study of hashing is closely related to the analysis of balls and bins; items are hashed to memory locations much as balls are thrown into bins. In particular, Azar et. al. [2] considered putting each ball in the less-full of two random bins. This lowers the probability that a bin exceeds a certain load from exponentially small to doubly exponential, giving maximum load log log n + O(1) with...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2013