The Alternative PHP Cache (APC) is a free and open opcode cache for PHP. Its goal is to provide a free, open, and robust framework for caching and optimizing PHP intermediate code.
【安装】-linux平台
1.pecl安装
pecl在php bin目录下面（PHP5.4.24）
--pecl install apc
2.源码安装
wget http://pecl.php.net/get/APC-3.0.19.tgz tar xzvf APC-3.0.19.tgz /usr/local/webserver/php/bin/phpize ./configure –enable-apc –enable-apc-mmap –with-php-config=/usr/local/webserver/php/bin/php-config –prefix=/usr/local/apc make && make install
【配置】
配置php.ini
[apc] extension=apc.so ;（要结合extension_dir，否则要全路径） apc.enabled = 1 ;（启用apc,0为禁用） apc.cache_by_default = on ;(File cache支持编译后的文件) apc.shm_segments = 1 ;（共享内存块数） apc.shm_size = 64 ;（共享内存大小） apc.ttl =0 ;（Time To Live nothing will be removed until the entire cache becomes full） apc.gc_ttl = 7200 ;(The number of seconds that a cache entry may remain on the garbage-collection list) apc.num_files_hint = 0 ;（number of distinct user cache variables to store. Set to zero or omit if not sure）
【测试】
拷贝apc.php到web目录下面（apc.php在php家目录的lib下面）
【参考】
http://blog.lixiphp.com/linux-php-apc-install-configuration/#axzz36OfJeWX2
http://www.jb51.net/article/38377.htm
http://purpen.iteye.com/blog/774790/
http://techportal.inviqa.com/2010/10/07/understanding-apc/