1. Create a src directory [Optional].
$ cd /usr/local/2. Download PCRE, the APC requires PCRE libraries and header files.
$ mkdir src
$ cd src
$ curl -O ftp://ftp.csx.cam.ac.uk//pub/software/programming/pcre/pcre-8.31.tar.gz3. Unzip the downloaded file.
$ tar -xvzf pcre-8.31.tar.gz4.Install PCRE.
$ cd pcre-8.315. Install APC.
$ ./configure
$ make
$ sudo make install
$ sudo pecl install apc6. Put the following line into the end of php.ini file.
$ extension=apc.so7. Make sure that you have completely install APC.
$ php -m | grep apc #should return "apc"