#41859 [NEW]: Low throughput with readfile/fpassthru

From: champs dot name at gmail dot com Operating system: Windows Server 2003/IIS6 PHP version: 5.2.3 PHP Bug Type: Performance problem Bug description: Low throughput with readfile/fpassthru Description: ------------ With a client using a 10Mbps connection, it is possible to saturate the pipe using print(fread(...)) in chunks of 32K or larger, but the throughput of fpassthru() and readfile() is consistently ~1/3 of that speed. On the other side of the coin, a client with sub-Mbit DSL is not able to complete 100MB downloads at all, unless readfile/fpassthru() is used. This has been tested in different orders, at different times of day, and on different, non-consecutive days. Reproduce code: --------------- if ($file = fopen($path, $mode)) { $chunk_size = 32; while(!feof($file)) { print(fread($file, $chunk_size * 1024)); if (connection_status() == 0) { flush(); } else { break; } } fclose($file); } Expected result: ---------------- Similar throughput if while() block is replaced with "fpassthru($file)" or "readfile($path)". Actual result: -------------- File is served at over 900kB/s with fread(), less than 300kB/s with fpassthru/readfile(). -- Edit bug report at http://bugs.php.net/?id=41859&edit=1 -- Try a CVS snapshot (PHP 4.4): http://bugs.php.net/fix.php?id=41859&r=trysnapshot44 Try a CVS snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=41859&r=trysnapshot52 Try a CVS snapshot (PHP 6.0): http://bugs.php.net/fix.php?id=41859&r=trysnapshot60 Fixed in CVS: http://bugs.php.net/fix.php?id=41859&r=fixedcvs Fixed in release: http://bugs.php.net/fix.php?id=41859&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=41859&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=41859&r=needscript Try newer version: http://bugs.php.net/fix.php?id=41859&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=41859&r=support Expected behavior: http://bugs.php.net/fix.php?id=41859&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=41859&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=41859&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=41859&r=globals PHP 3 support discontinued: http://bugs.php.net/fix.php?id=41859&r=php3 Daylight Savings: http://bugs.php.net/fix.php?id=41859&r=dst IIS Stability: http://bugs.php.net/fix.php?id=41859&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=41859&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=41859&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=41859&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=41859&r=mysqlcfg