#28260 [NEW]: readfile + session_start results in huge memory consumption

From: mb at diderot dot de Operating system: Linux PHP version: 4.3.6 PHP Bug Type: Session related Bug description: readfile + session_start results in huge memory consumption Description: ------------ When using readfile or fread in combination with session_start php seems to allocate memory for the whole filesize. Without session_start it doesn't. Replacing readfile by a fread loop doesn't make any difference. Reproduce code: --------------- <?php //error appears: session_start(); readfile('big.zip'); //big.zip > memory_limit ?> <?php //working fine: readfile('big.zip'); //big.zip > memory_limit ?> <?php //fread version, same error session_start(); $fp = fopen('big.zip'); while($d = fread($fp,4096)) { echo $d; flush(); } ?> Expected result: ---------------- Memory consumation should stay much bellow the whole filesize as it does without sessions. Actual result: -------------- apache error.log: Allowed memory size of 16777216 bytes exhausted (tried to allocate 138188800 bytes) -- Edit bug report at http://bugs.php.net/?id=28260&edit=1 -- Try a CVS snapshot (php4): http://bugs.php.net/fix.php?id=28260&r=trysnapshot4 Try a CVS snapshot (php5): http://bugs.php.net/fix.php?id=28260&r=trysnapshot5 Fixed in CVS: http://bugs.php.net/fix.php?id=28260&r=fixedcvs Fixed in release: http://bugs.php.net/fix.php?id=28260&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=28260&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=28260&r=needscript Try newer version: http://bugs.php.net/fix.php?id=28260&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=28260&r=support Expected behavior: http://bugs.php.net/fix.php?id=28260&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=28260&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=28260&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=28260&r=globals PHP 3 support discontinued: http://bugs.php.net/fix.php?id=28260&r=php3 Daylight Savings: http://bugs.php.net/fix.php?id=28260&r=dst IIS Stability: http://bugs.php.net/fix.php?id=28260&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=28260&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=28260&r=float