Hashing strings (v21)

Revision 21 of this benchmark created by brian blocker on

Description

Looking for the fastest hash function to get a unique id of a string.

Setup

function bitwise(str){
        var hash = 0;
        if (str.length == 0) return hash;
        for (i = 0; i < str.length; i++) {
            char = str.charCodeAt(i);
            hash = ((hash<<5)-hash)+char;
        }
        return hash;
    }
    
    function numbers(str) {
       var res = 0,
           len = str.length;
       for (var i = 0; i < len; i++) {
        res = res * 31 + str.charCodeAt(i);
       }
       return res;
      }
    
    function bitwiseconv(str){
        var hash = 0;
        if (str.length == 0) return hash;
        for (i = 0; i < str.length; i++) {
            char = str.charCodeAt(i);
            hash = ((hash<<5)-hash)+char;
            hash = hash & hash; // Convert to 32bit integer
        }
        return hash;
    }
    
    function numbersconv(str) {
       var res = 0,
           len = str.length;
       for (var i = 0; i < len; i++) {
        res = res * 31 + str.charCodeAt(i);
        res = res & res;
       }
       return res;
      }
    
    function hashCode (s){
      return s.split("").reduce(function(a,b){a=((a<<5)-a)+b.charCodeAt(0);return a&a},0);              
    }

Test runner

Ready to run.

Testing in
TestOps/sec
Bitwise based function (No integer conversion)
bitwise('[LOG] This is a a not-too-long log message, once that will commonly pop up in my application');
ready
Number based function (No integer conversion)
numbers('[LOG] This is a a not-too-long log message, once that will commonly pop up in my application');
ready
Bitwise based function
bitwiseconv('[LOG] This is a a not-too-long log message, once that will commonly pop up in my application');
ready
Number based function
numbersconv('[LOG] This is a a not-too-long log message, once that will commonly pop up in my application');
ready
hashCode('[LOG] This is a a not-too-long log message, once that will commonly pop up in my application')
ready

Revisions

You can edit these tests or add more tests to this page by appending /edit to the URL.