Bug #51466 [Fbk->NoF]: zlib.output_compression gets disabled on some processes

Edit report at https://bugs.php.net/bug.php?id=51466&edit=1 ID: 51466 Updated by: mike@php.net Reported by: radek at pinkbike dot com Summary: zlib.output_compression gets disabled on some processes -Status: Feedback +Status: No Feedback Type: Bug Package: Output Control Operating System: Centos 5.3 x86_64 PHP Version: 5.2.13 Assigned To: mike Block user comment: N Private report: N New Comment: No feedback was provided. The bug is being suspended because we assume that you are no longer experiencing the problem. If this is not the case and you are able to provide the information that was requested earlier, please do so and change the status of the bug back to "Open". Thank you. Previous Comments: ------------------------------------------------------------------------ [2011-09-19 14:42:58] mike@php.net Please try using this snapshot: http://snaps.php.net/php5.4-latest.tar.gz For Windows: http://windows.php.net/snapshots/ ------------------------------------------------------------------------ [2010-04-02 22:09:00] radek at pinkbike dot com Description: ------------ PHP 5.2.13 Linux r56 2.6.18-164.11.1.el5 #1 SMP Wed Jan 20 07:32:21 EST 2010 x86_64 x86_64 x86_64 GNU/LinuxApache/2.2.3 (CentOS) mod_ssl/2.2.3 OpenSSL/0.9.8e-fips-rhel5 On a fairly busy server, (50 php req/s) we see that some processes stop compressing page output. I have narrowed it down to where a process pid which transitions to this state, remains in this state until recycled/restarted (MaxRequestsPerChild reached). In this state, where gzip is not working, output headers do not contain Content encodign gzip, so the output is fine. It's just not using compression. So when all processes are restarted, page compression works correctly for some indeterminate time, after which, some processes transition to a state where they do not compress the output. Once in this state a process ALWAYS ignores the compression until recycled. Some additional info: We only run a max limit of 100 processes, and typically active processes are about 20 or so. I have decreased MaxRequestsPerChild to about 40,000 which recycles processes every 2 hours or so, and we still see about 50% of our pages delivered without compression. Expected result: ---------------- The problem happens with zlib.output_compression on. If I use output_handler = ob_gzhandler, compression never degrades, and it works as expected. Actual result: -------------- I am not sure what the trigger is but would like to help solve this issue. If someone can give me some insight into this I can debug further. ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=51466&edit=1