php8 , JIT(Just-In-Time) 성능 측정

* opcache와 jit 차이
OpCache (php5.5): 인터프리터가 생성한 OPCode를 메모리에 저장하여 실행

    - 저장한 OPCode를 실행할때도 VM을 거처서 CPU에서 실행됨

 

JIT (php8.0) : JIT(Just-In-Time) 컴파일러가 생성한 기계어를 메모리 저장하여 실행

    - 저장한 기계어 코드는 CPU에서 바로 실행됨

 

https://php.watch/versions/8.0/JIT

//-------------------------------------
php.ini 파일 설정
opcache.enable=1
opcache.enable_cli=1
opcache.jit_buffer_size=256M
opcache.jit=tracing

//-------------------------------------
opcode.jit 옵션
    disable : 완전 불가
    off : 불가, 런타임에서 동작시키기 가능
    on : tracing과 동일
    tracing :  1254 (CRTO)
    function :  1205 (CRTO)
    4자리숫자 : CRTO

C: CPU-specific Optimization Flags
    0: Disable CPU-specific optimization.
    1: Enable use of AVX, if the CPU supports it.

R: Register Allocation
    0: Don't perform register allocation.
    1: Perform block-local register allocation.
    2: Perform global register allocation.

T: Trigger
    0: Compile all functions on script load.
    1: Compile all functions on first execution.
    2: Profile first request and compile the hottest functions afterwards.
    3: Profile on the fly and compile hot functions.
    4: Currently unused.
    5: Use tracing JIT. Profile on the fly and compile traces for hot code segments.

O: Optimization Level
    0: No JIT.
    1: Minimal JIT (call standard VM handlers).
    2: Inline VM handlers.
    3: Use type inference.
    4: Use call graph.
    5: Optimize whole script.

//-------------------------------------

opcache.jit 옵션 값에 따른 성능 측정 결과

    - tracing은 20-30%, function은 10-15% 성능 향상

 

    - 초당 실행수

	코드1	코드2	코드3	opcache_get_status()['jit'] 결과값 kind, opt_level, opt_flags
disable	2439	2030	343	000
off	2439	2040	351	000
on	2962	2631	462	546
tracing(1254)	2857	2285	441	546
1254	2985	2631	466	546
function(1205)	2666	2352	401	056
1205	2941	2597	458	056
1255	2962	2614	475	556

 

//-----------------------------------------------------------------------------

 

The Definitive PHP 7.2, 7.3, 7.4, 8.0, and 8.1 Benchmarks (2022) 
https://kinsta.com/blog/php-benchmarks/

PHP 8.1 Performance Is Continuing To Improve With Early Benchmarks
https://www.phoronix.com/scan.php?page=news_item&px=PHP-8.1-Benchmarks-Perf-Early

PHP 8: JIT performance in real-life web applications
https://stitcher.io/blog/jit-in-real-life-web-applications


Just-In-Time (JIT) Compilation in PHP 8.0
https://lindevs.com/just-in-time-jit-compilation-in-php-8-0/

 

//-------------------------------------

https://www.php.net/releases/8.0/en.php

//-------------------------------------

 

벤치마크 소스
https://github.com/php/php-src/blob/master/Zend/bench.php


https://stitcher.io/blog/preloading-in-php-74
https://www.cloudpanel.io/docs/v1/guides/php/opcache-preload