APC 는 업데이트된지 오래 되었고 PHP 5.5 에서는 지원하지 않으므로 PHP 5.5 부터 내장된 Zend OPcache 를 사용하는 걸 권장한다.

Windows

http://dev.freshsite.pl/php-accelerators/apc.html 에서 다운로드 및 압축 해제
1. Win7/2008 용 다운로드 - php_apc_3114_beta_php54_win7-2008.zip
파일중에 php_apc.dll를 PHP 설치 폴더내 ext 에 복사

c:\windows\php.ini 에 다음 내용 추가

extension=php_apc_3114_beta_php54_win7-2008.dll

http://windows.php.net/downloads/pecl/releases/apc/에서 배포하는 apc 는 디버그 로그를 출력하는 치명적인 문제가 있어서 사용 불가

Notice: Unknown: 1. h->opened_path=[null] h->filename=[xxxx] in Unknown on line 0

Notice: Unknown: apc_cache_find [-1302308902] in Unknown on line 0

RHEL /CentOS

WebTatic 이나 Remi 저장소 를 설치한다. (RHEL/CentOS php 5.4 설치 참고)
yum 으로 설치
```
yum install php54w-pecl-apc
```

공통 설정

php.ini 에 다음 내용 추가

Click here to expand...

[apc]
apc.enabled=1
apc.shm_segments=1
apc.shm_size=256M
;Relative to the number of cached files (you may need to watch your stats for a day or two to find out a good number)
apc.num_files_hint=7000
;Relative to the size of WordPress
apc.user_entries_hint=4096
;The number of seconds a cache entry is allowed to idle in a slot before APC dumps the cache
apc.ttl=7200
apc.user_ttl=7200
apc.gc_ttl=3600
;Setting this to 0 will give you the best performance, as APC will not have to check the IO for changes. However, you must clear the APC cache to recompile already cached files. If you are still developing, updating your site daily in WP-ADMIN, and running W3TC set this to 1
apc.stat=1
;This MUST be 0, WP can have errors otherwise!
apc.include_once_override=0
;Only set to 1 while debugging
apc.enable_cli=0
;Allow 2 seconds after a file is created before it is cached to prevent users from seeing half-written/weird pages
apc.file_update_protection=2
;Leave at 2M or lower. WordPress does't have any file sizes close to 2M
apc.max_file_size=2M
;Ignore files
;apc.filters = "/var/www/apc.php"
apc.cache_by_default=1
apc.use_request_time=1
apc.slam_defense=0
;;apc.mmap_file_mask=/var/www/temp/apc.XXXXXX
apc.stat_ctime=0
apc.canonicalize=1
apc.write_lock=1
apc.report_autofilter=0
apc.rfc1867=0
apc.rfc1867_prefix =upload_
apc.rfc1867_name=APC_UPLOAD_PROGRESS
apc.rfc1867_freq=0
apc.rfc1867_ttl=3600
apc.lazy_classes=0
apc.lazy_functions=0

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