#47643 [Com]: array_diff() takes over 3000 times longer than php 5.2.4

ID: 47643 Comment by: maarten at talkin dot nl Reported By: viper7 at viper-7 dot com Status: Assigned Bug Type: Performance problem Operating System: * PHP Version: 5.*, 6CVS (2009-04-13) Assigned To: felipe New Comment: Why dont you only reset ptr if (behavior & DIFF_ASSOC) ? Previous Comments: ------------------------------------------------------------------------ [2010-01-17 12:09:15] emiel dot bruijntjes at copernica dot com This bug is now open for 10 months. Are you still working on this? ------------------------------------------------------------------------ [2009-07-09 20:38:20] jani@php.net As Dmitry's noted, this is side-effect your fix caused. ------------------------------------------------------------------------ [2009-07-01 15:32:01] dmitry@php.net The problems occurs because of "bad" patch for bug #42838. The diff algorithm sorts arrays using qsort and then assumes that they are sorted correctly. But in case of user compaison function it can't be guaranteed. Thus in ext/standard/tests/array/bug42838.phpt key_compare_func() can't sort array correctly because expressions (0 < 'a') and (0 > 'a') both false ('a' is interpreted as a number 0). It should be fixed in some way ------------------------------------------------------------------------ [2009-06-30 15:22:24] derick@php.net Dmitry, could you have a look? I have no idea why this occurs. ------------------------------------------------------------------------ [2009-06-30 15:19:43] viper7 at viper-7 dot com I've tracked down the change that broke things, this is it. but the exact reason is beyond me heh. Hopefully this helps. http://cvs.php.net/viewvc.cgi/php-src/ext/standard/array.c?r1=1.308.2.21.2.51&r2=1.308.2.21.2.52&pathrev=PHP_5_2 ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at http://bugs.php.net/47643 -- Edit this bug report at http://bugs.php.net/?id=47643&edit=1