[asterisk-bugs] [Asterisk 0019233]: Adding the Move to Front Hash functionality

[Asterisk Bug Tracker]

The following issue has been RESOLVED. 
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https://issues.asterisk.org/view.php?id=19233 
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Reported By:                schmidts
Assigned To:                schmidts
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Project:                    Asterisk
Issue ID:                   19233
Category:                   General
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     resolved
Asterisk Version:           SVN 
JIRA:                        
Regression:                 No 
Reviewboard Link:           https://reviewboard.asterisk.org/r/1201/ 
SVN Branch (only for SVN checkouts, not tarball releases):  trunk 
SVN Revision (number only!): 316961 
Request Review:              
Resolution:                 fixed
Fixed in Version:           
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Date Submitted:             2011-05-05 02:04 CDT
Last Modified:              2011-05-05 02:09 CDT
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Summary:                    Adding the Move to Front Hash functionality
Description: 
the so called "move to front" MTF functionality is a well known and
documented improvement for hashes to improve the speed and accesstime for
each object in the hash.
The idea of MTF is very simple. If you have a match on the object you
searched, just move this object to the first position in the bucket. This
operation is just a pointer exchange which means its cheap but could
improve the performance well.

MTF works best when the spread over the buckets isnt well or if there are
more objects than buckets. It will not help if there are only very few
objects.

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 (0134467) svnbot (reporter) - 2011-05-05 02:09
 https://issues.asterisk.org/view.php?id=19233#c134467 
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Repository: asterisk
Revision: 316962

U   trunk/main/astobj2.c

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r316962 | schmidts | 2011-05-05 02:09:21 -0500 (Thu, 05 May 2011) | 10
lines

Adding the Move to Front Hash functionality

Moving a found object to the front of its bucket to reduce the necessary
traversal steps to find an object. This change improves the search time on
large system with many data or in link lists.

(closes issue https://issues.asterisk.org/view.php?id=19233)
Reported by: schmidts

Review: https://reviewboard.asterisk.org/r/1201/


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http://svn.digium.com/view/asterisk?view=rev&revision=316962 

Issue History 
Date Modified    Username       Field                    Change               
====================================================================== 
2011-05-05 02:09 svnbot         Note Added: 0134467                          
2011-05-05 02:09 svnbot         Status                   new => assigned     
2011-05-05 02:09 svnbot         Assigned To               => schmidts        
2011-05-05 02:09 svnbot         Status                   assigned => resolved
2011-05-05 02:09 svnbot         Resolution               open => fixed       
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