Bug #70341 [Opn]: Weird behaviour of memory_get and peak_usage
| From: | quantuumsnot at gmail dot com | Date: | Mon, 24 Aug 2015 12:46:00 +0000 |
| Subject: | Bug #70341 [Opn]: Weird behaviour of memory_get and peak_usage | ||
| References: | 1 | Groups: | php.bugs |
| Request: | Send a blank email to php-bugs+get-195471@lists.php.net to get a copy of this message | ||
Edit report at https://bugs.php.net/bug.php?id=70341&edit=1
ID: 70341
User updated by: quantuumsnot at gmail dot com
Reported by: quantuumsnot at gmail dot com
Summary: Weird behaviour of memory_get and peak_usage
Status: Open
Type: Bug
Package: *General Issues
Operating System: windows 7 x64
PHP Version: 7.0.0RC1
Block user comment: N
Private report: N
New Comment:
To be precise - using false gives me 0 bytes, using true gives me a rly big difference in bytes used
Previous Comments:
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[2015-08-24 12:42:08] quantuumsnot at gmail dot com
Description:
------------
I usually use this short script to test some home-brew functions but noticed a inconsistency in
memory_get_usage() and memory_get_peak_usage()
Corresponding to docs, when using:
FALSE parameter - emalloc() returns bytes used by the script
TRUE parameter - returns bytes allocated by OS
The problem is that the script worked on PHP 5.6.8 x64 Thread Safe - returned bytes are above 0, but
in 7.0.0RC1 this returns 0
The fix is to use at line #1 memory_get_usage(false) which returns 40-50 times!!! bigger memory
usage (for example 1.6-1.8MB instead of 40-45KB)
Tested it on 3v4l.org and the results are the same, 5.5.0-5.6.12 always win
What is the correct way to benchmark my code in PHP7 using pure PHP? (do not suggest xdebug or
frameworks, please)
Test script:
---------------
$memoryUsage = memory_get_peak_usage(false);
someFunctionCalled();
$memoryUsage = abs(memory_get_peak_usage(false) - $memoryUsage);
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Edit this bug report at https://bugs.php.net/bug.php?id=70341&edit=1