From: Operating system: Red Hat Linux PHP version: 5.2.17 Package: Unknown/Other Function Bug Type: Bug Bug description:debug_backtrace increases memory usage
Description: ------------ Calling debug_backtrace(false) can lead to a huge increase in memory usage, if it's called from within a function that was passed a huge string as an argument. This is because the string will be duplicated in the "args" field of the result. It would be nice to have another boolean argument to debug_backtrace, that would tell it to skip the "args" field. This would be similar to the one that skips the "object" field. Or could the arguments be returned as references, so they don't increase memory usage? Test script: --------------- function test($str) { echo "before: ".round(memory_get_usage()/1024/1024, 2)." MB\n"; debug_backtrace(false); echo "after: ".round(memory_get_usage()/1024/1024, 2)." MB\n"; } test(str_repeat('a', 10000000)); Expected result: ---------------- before: 9.59 MB after: 9.59 MB (This is what I get if I remove the debug_backtrace() call.) Actual result: -------------- before: 9.59 MB after: 19.12 MB -- Edit bug report at http://bugs.php.net/bug.php?id=54147&edit=1 -- Try a snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=54147&r=trysnapshot52 Try a snapshot (PHP 5.3): http://bugs.php.net/fix.php?id=54147&r=trysnapshot53 Try a snapshot (trunk): http://bugs.php.net/fix.php?id=54147&r=trysnapshottrunk Fixed in SVN: http://bugs.php.net/fix.php?id=54147&r=fixed Fixed in SVN and need be documented: http://bugs.php.net/fix.php?id=54147&r=needdocs Fixed in release: http://bugs.php.net/fix.php?id=54147&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=54147&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=54147&r=needscript Try newer version: http://bugs.php.net/fix.php?id=54147&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=54147&r=support Expected behavior: http://bugs.php.net/fix.php?id=54147&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=54147&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=54147&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=54147&r=globals PHP 4 support discontinued: http://bugs.php.net/fix.php?id=54147&r=php4 Daylight Savings: http://bugs.php.net/fix.php?id=54147&r=dst IIS Stability: http://bugs.php.net/fix.php?id=54147&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=54147&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=54147&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=54147&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=54147&r=mysqlcfg