APC (Alternative PHP Cache) is a PHP extension that caches and optimizes the opcodes generated by the Zend Engine. It stores precompiled PHP scripts in shared memory, improving performance by avoiding the need to parse and compile scripts on each request. APC offers opcode caching, content caching using functions like apc_add(), and upload progress reporting. Benchmark tests showed that using APC can nearly double the requests per second and reduce the average request time by over half compared to not using a opcode cache.

1. Serban Nicolae [email_address] Netbridge Development SRL APC - Alternative PHP Cache opcode cache

2. APC - Alternative PHP Cache Anatomia unui request php

3. APC Instalare

4. Facilitati oferite

5. Configurare

6. Teste

7. APC - Alternative PHP Cache Anatomia unui request php <?php $a = 1; $b = 2; $c = $a + $b; echo $c; ?> Exemplu: play.php

8. APC - Alternative PHP Cache Read Output Parse Compile Execute play.php Anatomia unui request php

9. APC - Alternative PHP Cache Output Parse Compile Execute play.php Anatomia unui request php Read Server API ( SAPI) - mod_php ( Apache 2) - FastCGI ( Lighttpd, Nginx ) - php-fpm ( Lighttpd, Nginx )

10. APC - Alternative PHP Cache Output Compile Execute Anatomia unui request php Read Parsarea - Se parcurge codul sursa si se genereaza o serie de token-uri pentru fiecare cuvant din codul sursa. - Se analizeaza token-urile si se determina structura lor gramaticala. - Se compara structura gramaticala cu cea definita in regulile de sintaxa ale limbajului. Parse Exemplu greseala de sintaxa: PHP Parse error: syntax error, unexpected T_VARIABLE in play.php on line 3

11. APC - Alternative PHP Cache Anatomia unui request php <?php $a = 1; $b = 2; $c = $a + $b; echo $c; ?> T_OPEN_TAG :: <?php T_WHITESPACE :: T_VARIABLE :: $a = T_LNUMBER :: 1 T_WHITESPACE :: T_VARIABLE :: $b = T_LNUMBER :: 2 ; T_WHITESPACE :: T_VARIABLE :: $c = T_VARIABLE :: $a + T_VARIABLE :: $b ; T_WHITESPACE :: T_ECHO :: echo T_WHITESPACE :: T_VARIABLE :: $c ; T_WHITESPACE :: T_CLOSE_TAG :: ?> Parsare * Cu ajutorul functiilor PHP token_get_all(<STRING>) si token_name(<INT>)

12. APC - Alternative PHP Cache Output Execute Anatomia unui request php Read Compilarea - Se face doar in cazul in care nu exista greseli de sintaxa. - Generarea de bytecode ( numit opcode ) pe baza codului sursa. - Codul opcode este generat de catre Zend Engine - Rularea lui se face tot de catre Zend Engine Exemple de instructiuni opcode intelese de Zend Engine: NOP, ADD, DIV, IS_EQUAL, ASSIGN_ADD, CAST .... Lista completa: http://www.php.net/manual/en/internals2.opcodes.list.php Parse Compile

13. APC - Alternative PHP Cache Output Execute Anatomia unui request php Read Parse Compile Finding entry points Branch analysis from position: 0 Return found filename: /media/projects/play/public/play.php function name: (null) number of ops: 6 compiled vars: !0 = $a, !1 = $b, !2 = $c line # * op fetch ext return operands --------------------------------------------------------------------------------- 2 0 > ASSIGN !0, 1 3 1 ASSIGN !1, 2 4 2 ADD ~2 !0, !1 3 ASSIGN !2, ~2 5 4 ECHO !2 7 5 > RETURN 1 branch: # 0; line: 2- 7; sop: 0; eop: 5 OPCODE play.php * Cu ajutorul extensiei PHP Vulcan Logic Disassembler (VLD)

14. APC - Alternative PHP Cache Output Execute Anatomia unui request php Read Parse Compile Pentru fiecare fisier cod sursa php dintr-un proiect web se efectueaza parsarea si compilarea lui la fiecare cerere catre serverul web. Pe masinile de productie codul sursa al fisierelor se modifica foarte rar . Cum se poate imbunatatii timpul de executie ...

15. APC - Alternative PHP Cache Read Output Parse Compile Execute play.php Cache opcode PHP

16. APC - Alternative PHP Cache A lternative P HP C ache ( APC ) Este o extensie pentru php care realizeaza cache pentru codul intern al lui Zend Engine si anume opcode . Cachul este tinut in RAM. Instalarea se face cu ajutorul PECL pecl install apc Se configureaza cu ajutorul fisierului php.ini Se doreste introducerea extensiei in Core incepand cu PHP 6. Extensia ofera un set de functii pentru manevrarea cache-ului. Este dezvoltata de comunitatea php.net