Bug #51382 [Com]: session_start() blocks execution

Edit report at http://bugs.php.net/bug.php?id=51382&edit=1 ID: 51382 Comment by: abca_b_cabcom at hotmail dot com Reported by: info at lategoodbye dot de Summary: session_start() blocks execution Status: Open Type: Bug Package: Session related Operating System: Linux 2.4.35.4 mips PHP Version: 5.3.2 New Comment: From you description I traced back to the line 1475 in ./etc/session/session.c, it is the only line which will be affect by the php.ini variable session.gc_divisor you describe. The line is show below: nrand = (int) ((float) PS(gc_divisor) * php_combined_lcg(TSRMLS_C)); So, I think it may be a compiling error. Previous Comments: ------------------------------------------------------------------------ [2010-03-24 19:04:24] rasmus@php.net One way to figure that out is to attach gdb to a hanging fcgi process and get a backtrace (bt) from gdb which should show where it is stuck. ------------------------------------------------------------------------ [2010-03-24 18:44:22] info at lategoodbye dot de Description: ------------ Hi, i'm running PHP 5.3.2 via FastCGI with lighttpd 1.4.25 and uclibc 0.9.29. I experienced that after a period of time, all session driven pages hang and deliver no content to the client. But all static content like images are accessible. Below i appended a little script, how the problem can be reproduced. Here are the options from the php.ini: session.save_handler = files session.save_path = "/tmp" session.gc_probability = 1 session.gc_divisor = 100 session.gc_maxlifetime = 1440 Here is the configure line: './configure' '--target=mipsel-linux' '--host=mipsel-linux' '--build=i486-linux-gnu' '--program-prefix=' '--program-suffix=' '--prefix=/usr' '--exec-prefix=/usr' '--bindir=/usr/bin' '--sbindir=/usr/sbin' '--libexecdir=/usr/lib' '--sysconfdir=/etc' '--datadir=/usr/share' '--localstatedir=/var' '--mandir=/usr/man' '--infodir=/usr/info' '--disable-nls' '--enable-shared' '--disable-static' '--disable-rpath' '--disable-debug' '--without-pear' '--with-config-file-path=/etc' '--enable-magic-quotes' '--disable-short-tags' '--without-gettext' '--disable-simplexml' '--with-zlib=/home/10_openwrt/staging_dir/mipsel/usr' '--with-zlib-dir=/home/10_openwrt/staging_dir/mipsel/usr' '--with-pcre-regex=/home/10_openwrt/staging_dir/mipsel/usr' '--disable-phar' '--enable-ctype=shared' '--without-curl' '--disable-fileinfo' '--disable-dom' '--disable-exif' '--disable-ftp' '--without-gd' '--without-gmp' '--disable-hash' '--without-iconv' '--enable-json=shared' '--without-ldap' '--disable-mbstring' '--without-mcrypt' '--without-mysql' '--without-openssl' '--enable-pdo=shared' '--without-pdo-mysql' '--without-pdo-pgsql' '--with-pdo-sqlite=shared,/home/10_openwrt/staging_dir/mipsel/usr' '--without-pgsql' '--enable-session=shared' '--disable-soap' '--enable-sockets=shared' '--without-sqlite' '--with-sqlite3=shared,/home/10_openwrt/staging_dir/mipsel/usr' '--disable-tokenizer' '--enable-xml=shared,/home/10_openwrt/staging_dir/mipsel/usr' '--with-libexpat-dir=/home/10_openwrt/staging_dir/mipsel/usr' '--disable-xmlreader' '--disable-xmlwriter' '--disable-apc' '--disable-filter' '--disable-libxml' '--enable-sysvsem' '--enable-sysvshm' '--enable-sysvmsg' '--enable-pcntl' '--disable-cli' '--enable-cgi' The filesystem behind /tmp is tmpfs. After that i played a little bit with option session.gc_divisor. If i set the option to 2, then the problem happend immediately. But if i set the option to 100000, the problem is not reproducable. Is this a dead lock caused by the session garbage collector? Test script: --------------- <?php session_start(); session_write_close(); ?> <html><body>Content</body></html> Expected result: ---------------- PHP delivers "Content" to the browser. Actual result: -------------- The browser didn't get "Content" and wait for a response. ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/bug.php?id=51382&edit=1