Bug #74174 [NEW]: Memory allocation problem

From: enleury at gmail dot com Operating system: Ubuntu PHP version: 7.1.2 Package: Performance problem Bug Type: Bug Bug description:Memory allocation problem Description: ------------ Memory is not freed after return from the method. Looks like a heap defragmentation issue (https://bugs.php.net/bug.php?id=53669), but it works fine on 5.x branches. Online test script for 5.x and 7.x branches: https://3v4l.org/2OVeU#output Test script: --------------- <?php function create_docs($amount) { $documents = []; for ($i = 0; $i < $amount; $i++) { $documents[] = ['a' => $i]; } } echo memory_get_usage(true), PHP_EOL; create_docs(5000); echo memory_get_usage(true), PHP_EOL; create_docs(50000); echo memory_get_usage(true), PHP_EOL; create_docs(5000); echo memory_get_usage(true), PHP_EOL; Expected result: ---------------- 262144 524288 524288 524288 Actual result: -------------- 2097152 4194304 20971520 20971520 -- Edit bug report at https://bugs.php.net/bug.php?id=74174&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=74174&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=74174&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=74174&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=74174&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=74174&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=74174&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=74174&r=needscript Try newer version: https://bugs.php.net/fix.php?id=74174&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=74174&r=support Expected behavior: https://bugs.php.net/fix.php?id=74174&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=74174&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=74174&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=74174&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=74174&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=74174&r=dst IIS Stability: https://bugs.php.net/fix.php?id=74174&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=74174&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=74174&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=74174&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=74174&r=mysqlcfg