#45296 [NEW]: some string funcs need unexpectedly high memory_limit

From: louis at steelbytes dot com Operating system: windows PHP version: 5.2.6 PHP Bug Type: Performance problem Bug description: some string funcs need unexpectedly high memory_limit Description: ------------ the following code fails with Fatal error: Allowed memory size of 587896 bytes exhausted (tried to allocate 262145 bytes) command: php.exe -n -f memuse.php memuse.php: @ob_end_flush(); @ob_implicit_flush(1); define('big_size',256*1024); define('saftey',4*1024); ini_set('memory_limit',memory_get_usage()+big_size*2+saftey); $big = str_repeat('x',big_size); yet if I change big_size to 1024*1024, then it works? and a simlar script @ob_end_flush(); @ob_implicit_flush(1); define('big_size',200*1024); define('saftey',4*1024); ini_set('memory_limit',memory_get_usage()+big_size+saftey); echo str_repeat('x',big_size); also fails, yet if I change big_size to 180*1024 then it works? PS, note that in the first script I set mem limit to 2 times big_size, and in the 2nd script I did not. Reproduce code: --------------- see above Expected result: ---------------- see above Actual result: -------------- see above -- Edit bug report at http://bugs.php.net/?id=45296&edit=1 -- Try a CVS snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=45296&r=trysnapshot52 Try a CVS snapshot (PHP 5.3): http://bugs.php.net/fix.php?id=45296&r=trysnapshot53 Try a CVS snapshot (PHP 6.0): http://bugs.php.net/fix.php?id=45296&r=trysnapshot60 Fixed in CVS: http://bugs.php.net/fix.php?id=45296&r=fixedcvs Fixed in release: http://bugs.php.net/fix.php?id=45296&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=45296&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=45296&r=needscript Try newer version: http://bugs.php.net/fix.php?id=45296&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=45296&r=support Expected behavior: http://bugs.php.net/fix.php?id=45296&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=45296&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=45296&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=45296&r=globals PHP 4 support discontinued: http://bugs.php.net/fix.php?id=45296&r=php4 Daylight Savings: http://bugs.php.net/fix.php?id=45296&r=dst IIS Stability: http://bugs.php.net/fix.php?id=45296&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=45296&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=45296&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=45296&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=45296&r=mysqlcfg