Suggest people use the JIT on PHP 8+

[iamacarpet]

Feature request

It might be helpful for others to suggest that people enable the JIT when using this project with PHP 8+

We had a legacy project that was taking ~375s per run (without the cache file), but enabling the JIT brings this down to ~150s.

We are running with:

php -n -dmemory_limit=12G -dzend_extension=opcache.so -dopcache.enable_cli=On -dopcache.jit_buffer_size=128M vendor/bin/php-cs-fixer fix --config=...

[SpacePossum]

Hi and thanks for sharing!

Interesting numbers, when you say enabling JIT do you mean enabling the op cache on cli? Sorry for asking, I haven't looked into JIT configuration (yet) I'm afraid...

[Wirone]

@iamacarpet answered:

Kind of, opcache & JIT are tied together in their config options, but perform different functions.

opcache is a cache of ‘code -> byte code’

JIT is a cache of ‘byte code -> machine code’

Basically bridges the performance gab between an interpreted language like PHP and a compiled language like C++ (although not entirely).

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(Moved to thread to utilise discussions better)

[keradus]

Maybe it's sth we can use when spinning worker command ?

[Wirone]

I am not sure if it's related to parallel runner. It should rather be verified in main process and reported regardless of the runner used.

[keradus]

• main process can report it to end user to enable it
• main process can enable it themselve for worker processes, can't it ?

[Wirone]

Ah, I thought about reporting from workers, but you mean setting this in process' command to ensure it's enabled. Yeah, that could work, worth checking. But I won't do this in #7777, it's an improvement that can be implemented later ☺️.

[iamacarpet]

Thanks for posting a reference to #7777, just been catching up.

It looks like instead of enabling the required php.ini config options as command line arguments, when running in a container (like with a CI/CD type setup), it should be possible to just write out to the php.ini file before running the command.

It would be interesting to see in your benchmarks for #7777 what the difference is with JIT vs parallel, then JIT + parallel for maximum improvement.

[Wirone]

@iamacarpet I believe you can fiddle with it if you want, just checkout my branch and modify ProcessFactory accordingly. It would certainly be helpful 😊.