Doc #75247 [NEW]: Documentation Recommends Broken Setting

From: pegasus at vaultwiki dot org Operating system: PHP version: 5.6.31 Package: opcache Bug Type: Documentation Problem Bug description:Documentation Recommends Broken Setting Description: ------------ --- From manual page: http://www.php.net/opcache.installation --- The page recommends using directive opcache.fast_shutdown = 1, however this directive is known to be broken. See the following Zend bug which has remained unsolved since 2013: https://github.com/zendtech/ZendOptimizerPlus/issues/146 In my experiences on many clients' servers, fast_shutdown occasionally caused PHP<->web server communication to fail and the PHP process to crash in random places without a segfault. In a number of cases, this led to database corruption. Disabling opcache.fast_shutdown always resolved the issue. Since opcache.fast_shutdown bypasses PHP garbage collection in favor of Zend MM garbage collection, it is likely that Zend MM is not doing this successfully, possibly creating a Use-Again-Without-Free? situation which causes the next process to crash. However, without segfaults to provide information, this is only a theory. Expected result: ---------------- The documentation should not recommend opcache.fast_shutdown = 1 until the Zend bug is fixed: https://github.com/zendtech/ZendOptimizerPlus/issues/146 If the Zend bug is fixed, the documentation should specify which version(s) of PHP the fix applies in, and therefore which version of PHP opcache.fast_shutdown becomes safe to use again. -- Edit bug report at https://bugs.php.net/bug.php?id=75247&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=75247&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=75247&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=75247&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=75247&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=75247&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=75247&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=75247&r=needscript Try newer version: https://bugs.php.net/fix.php?id=75247&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=75247&r=support Expected behavior: https://bugs.php.net/fix.php?id=75247&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=75247&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=75247&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=75247&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=75247&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=75247&r=dst IIS Stability: https://bugs.php.net/fix.php?id=75247&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=75247&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=75247&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=75247&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=75247&r=mysqlcfg