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diff --git a/ext/opcache/README b/ext/opcache/README new file mode 100644 index 0000000000..693a7b4e3c --- /dev/null +++ b/ext/opcache/README @@ -0,0 +1,220 @@ +The Zend OPcache +================ + +The Zend OPcache provides faster PHP execution through opcode caching and +optimization. It improves PHP performance by storing precompiled script +bytecode in the shared memory. This eliminates the stages of reading code from +the disk and compiling it on future access. In addition, it applies a few +bytecode optimization patterns that make code execution faster. + +Compatibility +------------- + +This version of Zend OPcache is compatible with PHP 5.2.*, 5.3.*, 5.4.* +and PHP-5.5 development branch. PHP 5.2 support may be removed in the future. + +Quick Install +------------- + +- Compile + + $PHP_DIR/bin/phpize + ./configure \ + --with-php-config=$PHP_DIR/bin/php-config + make + +- Install + + make install # this will copy opcache.so into PHP extension directory + +- Edit php.ini + + zend_extension=/...full path.../opcache.so + +NOTE: In case you are going to use Zend OPcache together with Xdebug or Zend Debugger, +be sure that the debugger is loaded after OPcache. "php -v" must show the debugger +after OPcache. + +- Restart PHP + +Speed Tuning +------------- + +We recommend the following configuration options for best performance +in a production environment. + +opcache.memory_consumption=128 +opcache.interned_strings_buffer=8 +opcache.max_accelerated_files=4000 +opcache.revalidate_freq=60 +opcache.fast_shutdown=1 +opcache.enable_cli=1 + +You also may add the following, but it may break some applications and +frameworks. Please, read description of these directives and add them on your +own risk. + +opcache.save_comments=0 +opcache.enable_file_override=1 + +In some cases you may like to prefer enabling/disabling some features +to avoid incompatibilities at the cost of some performance degradation. + +For development environment we would recommend setting opcache.revalidate_freq +into 0. + +Configuration Directives +------------------------ + +opcache.enable (default "1") + OPcache On/Off switch. When set to Off, code is not optimized and cached. + +opcache.enable_cli (default "0") + Enables the OPcache for the CLI version of PHP. It's mostly for testing + and debugging. + +opcache.memory_consumption (default "64") + The OPcache shared memory storage size. The amount of memory for storing + precompiled PHP code in Mbytes. + +opcache.interned_strings_buffer (default "4") + The amount of memory for interned strings in Mbytes. + +opcache.max_accelerated_files (default "2000") + The maximum number of keys (scripts) in the OPcache hash table. + The number is actually the first one in the following set of prime + numbers that is bigger than the one supplied: { 223, 463, 983, 1979, 3907, + 7963, 16229, 32531, 65407, 130987, 262237, 524521, 1048793 }. Only numbers + between 200 and 1000000 are allowed. + +opcache.max_wasted_percentage (default "5") + The maximum percentage of "wasted" memory until a restart is scheduled. + +opcache.use_cwd (default "1") + When this directive is enabled, the OPcache appends the current working + directory to the script key, thus eliminating possible collisions between + files with the same name (basename). Disabling the directive improves + performance, but may break existing applications. + +opcache.validate_timestamps (default "1") + When disabled, you must reset the OPcache manually or restart the + webserver for changes to the filesystem to take effect. + The frequency of the check is controlled by the directive + "opcache.revalidate_freq". + +opcache.revalidate_freq (default "2") + How often (in seconds) to check file timestamps for changes to the shared + memory storage allocation. ("1" means validate once per second, but only + once per request. "0" means always validate) + +opcache.file_update_protection (default "2") + Prevents caching files that are less than this number of seconds old. + It protects from caching of incompletely updated files. In case all file + updates on your site are atomic, you may increase performance setting it + to "0". + +opcache.revalidate_path (default "0") + Enables or disables file search in include_path optimization + If the file search is disabled and a cached file is found that uses + the same include_path, the file is not searched again. Thus, if a file + with the same name appears somewhere else in include_path, it + won't be found. Enable this directive if this optimization has an effect on + your applications. The default for this directive is disabled, which means + that optimization is active. + +opcache.save_comments (default "1") + If disabled, all PHPDoc comments are dropped from the code to reduce the + size of the optimized code. Disabling "Doc Comments" may break some + existing applications and frameworks (e.g. Doctrine, ZF2, PHPUnit) + +opcache.load_comments (default "1") + If disabled, PHPDoc comments are not loaded from SHM, so "Doc Comments" + may be always stored (save_comments=1), but not loaded by applications + that don't need them anyway. + +opcache.fast_shutdown (default "0") + If enabled, a fast shutdown sequence is used for the accelerated code + The fast shutdown sequence doesn't free each allocated block, but lets + the Zend Engine Memory Manager do the work. + +opcache.enable_file_override (default "0") + Allow file existence override (file_exists, etc.) performance feature. + +opcache.optimization_level (default "0xffffffff") + A bitmask, where each bit enables or disables the appropriate OPcache + passes + +opcache.inherited_hack (default "1") + Enable this hack as a workaround for "can't redeclare class" errors. + The OPcache stores the places where DECLARE_CLASS opcodes use + inheritance (These are the only opcodes that can be executed by PHP, + but which may not be executed because the parent class is missing due to + optimization). When the file is loaded, OPcache tries to bind the + inherited classes by using the current environment. The problem with this + scenario is that, while the DECLARE_CLASS opcode may not be needed for the + current script, if the script requires that the opcode at least be defined, + it may not run. The default for this directive is disabled, which means + that optimization is active. In php-5.3 and above this hack is not needed + anymore and this setting has no effect. + +opcache.dups_fix (default "0") + Enable this hack as a workaround for "Cannot redeclare class" errors. + +opcache.blacklist_filename + The location of the OPcache blacklist file (wildcards allowed). + Each OPcache blacklist file is a text file that holds the names of files + that should not be accelerated. The file format is to add each filename + to a new line. The filename may be a full path or just a file prefix + (i.e., /var/www/x blacklists all the files and directories in /var/www + that start with 'x'). Line starting with a ; are ignored (comments). + Files are usually triggered by one of the following three reasons: + 1) Directories that contain auto generated code, like Smarty or ZFW cache. + 2) Code that does not work well when accelerated, due to some delayed + compile time evaluation. + 3) Code that triggers an OPcache bug. + +opcache.max_file_size (default "0") + Allows exclusion of large files from being cached. By default all files + are cached. + +opcache.consistency_checks (default "0") + Check the cache checksum each N requests. + The default value of "0" means that the checks are disabled. + Because calculating the checksum impairs performance, this directive should + be enabled only as part of a debugging process. + +opcache.force_restart_timeout (default "180") + How long to wait (in seconds) for a scheduled restart to begin if the cache + is not being accessed. + The OPcache uses this directive to identify a situation where there may + be a problem with a process. After this time period has passed, the + OPcache assumes that something has happened and starts killing the + processes that still hold the locks that are preventing a restart. + If the log level is 3 or above, a "killed locker" error is recorded + in the Apache logs when this happens. + +opcache.error_log + OPcache error_log file name. Empty string assumes "stderr". + +opcache.log_verbosity_level (default "1") + All OPcache errors go to the Web server log. + By default, only fatal errors (level 0) or errors (level 1) are logged. + You can also enable warnings (level 2), info messages (level 3) or + debug messages (level 4). + +opcache.preferred_memory_model + Preferred Shared Memory back-end. Leave empty and let the system decide. + +opcache.protect_memory (default "0") + Protect the shared memory from unexpected writing during script execution. + Useful for internal debugging only. + +opcache.restrict_api (default "") + Allows calling OPcache API functions only from PHP scripts which path is + started from specified string. The default "" means no restriction. + +opcache.mmap_base + Mapping base of shared memory segments (for Windows only). All the PHP + processes have to map shared memory into the same address space. This + directive allows to manually fix the "Unable to reattach to base address" + errors. |