Req #67346 [Opn->Csd]: array_rand() performance issue

From: Date: Sat, 11 Mar 2017 18:15:30 +0000
Subject: Req #67346 [Opn->Csd]: array_rand() performance issue
References: 1  Groups: php.bugs 
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Edit report at https://bugs.php.net/bug.php?id=67346&edit=1

 ID:                 67346
 Updated by:         nikic@php.net
 Reported by:        v dot martyanov at drweb dot com
 Summary:            array_rand() performance issue
-Status:             Open
+Status:             Closed
 Type:               Feature/Change Request
 Package:            Arrays related
 Operating System:   Any
 PHP Version:        5.5.12
-Assigned To:        
+Assigned To:        nikic
 Block user comment: N
 Private report:     N

 New Comment:

PHP 7.1 uses a significantly faster array_rand() algorithm, especially for the num_req==1 case. It
is now O(1) instead of O(n).


Previous Comments:
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[2014-05-27 11:40:19] v dot martyanov at drweb dot com

Description:
------------
There is a performance issue in array_rand(). The problem is in using doubles instead of long
integers in the source.

In the case when num_req == 1 and num_avail < 256 it's not so hard to use tables with
precomputed values and avoid the usage of divisions and doubles.



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Edit this bug report at https://bugs.php.net/bug.php?id=67346&edit=1

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