Installation Instructions for APCu
---------------------------------

This version of APCu should work on PHP 4.3.0 - 4.4.x and
5.1.0 - 5.2.x.  Yes, that means PHP 5.0.x is no longer 
supported.  Upgrade to PHP 5.1.x or 5.2.x and you will 
notice all sorts of performance increases.

CVS Instructions
----------------
Building from CVS can be done like this:

  git clone https://github.com/krakjoe/apcu
  cd apcu
  phpize
  ./configure --with-php-config=/usr/local/php/bin/php-config
  make
  export TEST_PHP_ARGS='-n'
  make test
  make install

Suggested Configuration (in your php.ini file)
----------------------------------------------
  extension=apcu.so
  apc.enabled=1
  apc.shm_size=32M
  apc.ttl=7200
  apc.enable_cli=1

These are fully described at the bottom of this file.

+---------------------+
| QUICK INSTALL (DSO) |
+---------------------+

These instructions assume your PHP installation is located in /usr/local/php and you
want Apache optimizations (--with-apxs).

$ gunzip -c apcu_x.y.tar.gz | tar xf -
$ cd apcu_x.y
$ /path/to/phpize
$ ./configure [--with-php-config=/path/to/php-config]
$ make
$ make install

You will probably need to run the final command (make install) as root.

The above sequence of commands will install a .so file in your PHP
installation extension directory. The output of make install should display
that path to the screen.

Next you must edit your php.ini file, which is normally located in
/usr/local/php/lib/php.ini, and add the following line:

    extension="apcu.so"

Replace "/path/to/php/extensions" with whatever path was displayed when you
ran make install above.

Then restart your web server and consult the output of phpinfo(). If there is
an informational section for APCu, the installation was successful.

+------------------------+
| QUICK INSTALL (Static) |
+------------------------+

APCu will not successfully compile on all systems as a DSO. If you run into
problems using the DSO quick install, you can try to compile it statically
into PHP. (The DSO install is recommended, though.)

These instructions assume the current directory is the root of the PHP source
tree, and that you have already configured PHP by running its bundled
configure script.

$ cd ext
$ gunzip -c apcu_x.y.tar.gz | tar xf -
$ cd ..
$ ./buildconf
$ ./config.nice
$ make
$ make install

Once this is complete, simply restart your web server. You do not need to
modify your php.ini file to enable APCu.

+-----------------+
| VERBOSE INSTALL |
+-----------------+

These instructions assume your PHP installation is located in /usr/local/php.

1.  Unpack your distribution file.

    You will have downloaded a file named something like apcu_x.y.tar.gz.
    Unzip this file with a command like
    
        gunzip apcu_x.y.tar.gz
    
    Next you have to untar it with
    
        tar xvf apcu_x.y.tar

    This will create an apcu_x.y directory. cd into this new directory:

        cd apcu_x.y

2.  Run phpize.

    phpize is a script that should have been installed with PHP, and is
    normally located in /usr/local/php/bin assuming you installed PHP in
    /usr/local/php. (If you do not have the phpize script, you must reinstall
    PHP and be sure not to disable PEAR.)

    Run the phpize command:
    
        /usr/local/php/bin/phpize

    Its output should resemble this:

        autoheader: `config.h.in' is created
        You should update your `aclocal.m4' by running aclocal.
        Configuring for:
          PHP Api Version:   20020918
          Zend Module Api No:   20020429
          Zend Extension Api No:   20021010
 
    phpize should create a configure script in the current directory. If you
    get errors instead, you might be missing some required development tools,
    such as autoconf or libtool. You can try downloading the latest versions
    of those tools and running phpize again.
 
3.  Run the configure script.
 
    phpize creates a configure script. The only option you need to specify is
    the location of your php-config script:

        ./configure --enable-apcu [--with-php-config=/path/to/php-config]

4.  Compile and install the files. Simply type: make install

    (You may need to be root in order to install)

    If you encounter errors from libtool or gcc during this step, please
    contact the project maintainer (dcowgill@php.net).

5.  Edit your php.ini

    make install should have printed a line resembling the following:

        Installing shared extensions: /path/to/extension/

    Copy the path /path/to/extension/ and add the following line to your
    php.ini file (normally located in /usr/local/php/lib/php.ini):

        extension="apcu.so"

    If you don't have a php.ini file in that location, you can create it now.

6.  Restart the web server and test the installation.

    Restart your web server now (for apache, it's apachectl restart) and
    create a small test PHP file in your document root. The file should
    contain just the following line:

        <?php phpinfo() ?>

    Request that file in a web browser. If there is an entry for APCu in the
    list of installed modules, the installation was successful.

    If APCu is not listed, consult your web server error log. If it contains an
    error message saying that it can't load the APCu extension, your system
    might not be able to load shared libraries created with PHP's build
    system. One alternative would be to compile APCu statically into PHP. See
    the Quick Install (Static) instructions above.

    You should consult your error log anyway to see if APCu generated any
    errors. On BSD-based platforms, it is typical for APCu to be unable to
    allocate the default-sized shared memory segment. See below for hints on
    raising your system's shared memory limitations.

	+------------------+
	| CONFIGURING APCu |
	+------------------+

    OPTION                  DESCRIPTION
    ------------------      --------------------------------------------------
    apc.enabled             This can be set to 0 to disable APCu. This is
                            primarily useful when APCu is statically compiled
                            into PHP, since there is no other way to disable
                            it (when compiled as a DSO, the extension
                            line can just be commented-out).
                            (Default: 1)

    apc.enable_cli          Mostly for testing and debugging.  Setting this enables APCu
                            for the CLI version of PHP.  Normally you wouldn't want to
                            create, populate and tear down the APCu cache on every CLI
                            request, but for various test scenarios it is handy to be
                            able to enable APCu for the CLI version of APCu easily.
                            (Default: 0)

    apc.preload_path        Sets the path to text files containing caches to load
                            from disk upon intiialization of APCu.
                            preload_path should be a directory where each file follows
								$key.data
                            where $key should be used as the entry name and the contents
                            of the file contains serialized data to use as the value of
                            the entry.
                            (Default: null)

    apc.shm_size            The size of each shared memory segment in MB.
                            By default, some systems (including most BSD
                            variants) have very low limits on the size of a
                            shared memory segment. M/G suffixes must be used.
                            (Default: 32)
                            
    apc.shm_segments        The number of shared memory segments to allocate
                            for the compiler cache. If APCu is running out of
                            shared memory but you have already set
                            apc.shm_size as high as your system allows, you
                            can try raising this value.  Setting this to a
                            value other than 1 has no effect in mmap mode
                            since mmap'ed shm segments don't have size limits.
                            (Default: 1)

    apc.ttl                 The number of seconds a cache entry is allowed to
                            idle in a slot in case this cache entry slot is 
                            needed by another entry.  Leaving this at zero
                            means that your cache could potentially fill up
                            with stale entries while newer entries won't be
                            cached.  
                            (Default: 0)

    apc.gc_ttl              The number of seconds that a cache entry may
                            remain on the garbage-collection list. This value
                            provides a failsafe in the event that a server
                            process dies while executing a cached source file;
                            if that source file is modified, the memory
                            allocated for the old version will not be
                            reclaimed until this TTL reached. Set to zero to
                            disable this feature.
                            (Default: 3600)

	apc.smart				If you begin to get low on resources, an expunge of the cache
							is performed if it is less than half full. This is not always
							a suitable way of determining if an expunge of the cache
							should be per
							apc.smart allows you to set a runtime configuration value which
							is used to determine if an expunge should be run
							if (available_size < apc.smart * requested_size)
								apc_cache_expunge() 
							(Default: 0)

    apc.entries_hint        A "hint" about the number variables expected in the 
							cache. Set to zero or omit if you're not sure.
                            (Default: 4096)

    apc.mmap_file_mask      APCu is compiled by default with MMAP support.
                            This is the mktemp-style file_mask to pass to the
                            mmap module for determing whether your mmap'ed memory
                            region is going to be file-backed or shared memory
                            backed.  For straight file-backed mmap, set it to
                            something like /tmp/apc.XXXXXX (exactly 6 X's).
                            To use POSIX-style shm_open/mmap put a ".shm"
                            somewhere in your mask.  eg.  "/apc.shm.XXXXXX"
                            You can also set it to "/dev/zero" to use your 
                            kernel's /dev/zero interface to anonymous mmap'ed 
                            memory.  Leaving it undefined will force an 
                            anonymous mmap.
                            (Default: "")

    apc.slam_defense        On very busy servers whenever you start the server or
                            modify files you can create a race of many processes
                            all trying to cache the same data at the same time.
                            By default, APCu attempts to prevent "slamming" of a key.
                            A key is considered "slammed" if it was the last key set,
                            and a context other than the current one set it ( ie. it
							was set by another process or thread )
							Note:
								APCu does not store enough information to 
								catch every occurence, sufficient none the less.
                            (Default: 1)

    apc.serializer			Defines which serializer should be used. Default is the 
                            standard PHP serializer. Other can be used without having
                            to re compile apc, like igbinary for example.
                            (apc.serializer=igbinary)

	
		/* The remaining entries concern file upload progress support */


    apc.rfc1867             RFC1867 File Upload Progress hook handler is only available
                            if you compiled APCu against PHP 5.2.0 or later.  When enabled
                            any file uploads which includes a field called 
                            APCu_UPLOAD_PROGRESS before the file field in an upload form
                            will cause APCu to automatically create an upload_<key>
                            user cache entry where <key> is the value of the 
                            APCu_UPLOAD_PROGRESS form entry.

                            Note that the file upload tracking is not threadsafe at this
                            point, so new uploads that happen while a previous one is 
                            still going will disable the tracking for the previous.
                            (Default: 0)

    apc.rfc1867_prefix      Key prefix to use for the user cache entry generated by
                            rfc1867 upload progress functionality.  
                            (Default: "upload_")

    apc.rfc1867_name        Specify the hidden form entry name that activates APCu upload
                            progress and specifies the user cache key suffix.
                            (Default: "APCu_UPLOAD_PROGRESS")

    apc.rfc1867_freq        The frequency that updates should be made to the user cache
                            entry for upload progress.  This can take the form of a 
                            percentage of the total file size or a size in bytes 
                            optionally suffixed with 'k', 'm', or 'g' for kilobytes, 
                            megabytes, or gigabytes respectively (case insensitive).  
                            A setting of 0 updates as often as possible, which may cause 
                            slower uploads.
                            (Default: 0)
