JIT cause 100% cpu usage
Nobody has claimed this yet.
- Dominant language
- C
- Stars
- 40.4k
- Forks
- 8.1k
- Avg merge
- 2d 13h
- Merged PRs (30d)
- 96
Description
Description
The following code:
[opcache]
opcache.enable=1
opcache.enable_cli=1
opcache.memory_consumption=512
opcache.jit_buffer_size=256M
opcache.interned_strings_buffer=16
opcache.max_accelerated_files=200000
opcache.max_wasted_percentage=5
opcache.use_cwd=1
opcache.validate_timestamps=0
opcache.revalidate_freq=600
opcache.revalidate_path=0
opcache.save_comments=1
opcache.enable_file_override=0
opcache.optimization_level=0x7FFFBFFF
opcache.dups_fix=0
opcache.max_file_size=0
opcache.consistency_checks=0
opcache.force_restart_timeout=180
opcache.file_cache_only=0
opcache.file_cache_consistency_checks=1
opcache.huge_code_pages=1
opcache.preload=/path/to/config/preload.php
opcache.preload_user=user
Resulted in this output:
[18-Jul-2023 03:40:09] NOTICE: [pool www] child 179 started
Fatal error: Maximum execution time of 99+2 seconds exceeded (terminated) in /path/to/file.php on line 33
[18-Jul-2023 03:40:13] WARNING: [pool www] child 47 exited with code 124 after 381.082060 seconds from start
[18-Jul-2023 03:40:13] NOTICE: [pool www] child 182 started
Fatal error: Maximum execution time of 99+2 seconds exceeded (terminated) in /path/to/file.php on line 33
[18-Jul-2023 03:40:25] WARNING: [pool www] child 42 exited with code 124 after 393.292804 seconds from start
But I expected this output instead:
no errors in log
Hello,
after enabling JIT, our application start perform better (~10% faster). But, some php-fpm pods (~1 in 20) after start use all available cpu and timeout the requests. After pod restart, everything back to normal. Without JIT everything is ok and cpu utilization is at normal value.
Regards
opcache.blacklist_filename => no value => no value
opcache.consistency_checks => 0 => 0
opcache.dups_fix => Off => Off
opcache.enable => On => On
opcache.enable_cli => On => On
opcache.enable_file_override => Off => Off
opcache.error_log => no value => no value
opcache.file_cache => no value => no value
opcache.file_cache_consistency_checks => On => On
opcache.file_cache_only => Off => Off
opcache.file_update_protection => 2 => 2
opcache.force_restart_timeout => 180 => 180
opcache.huge_code_pages => On => On
opcache.interned_strings_buffer => 16 => 16
opcache.jit => tracing => tracing
opcache.jit_bisect_limit => 0 => 0
opcache.jit_blacklist_root_trace => 16 => 16
opcache.jit_blacklist_side_trace => 8 => 8
opcache.jit_buffer_size => 256M => 256M
opcache.jit_debug => 0 => 0
opcache.jit_hot_func => 127 => 127
opcache.jit_hot_loop => 64 => 64
opcache.jit_hot_return => 8 => 8
opcache.jit_hot_side_exit => 8 => 8
opcache.jit_max_exit_counters => 8192 => 8192
opcache.jit_max_loop_unrolls => 8 => 8
opcache.jit_max_polymorphic_calls => 2 => 2
opcache.jit_max_recursive_calls => 2 => 2
opcache.jit_max_recursive_returns => 2 => 2
opcache.jit_max_root_traces => 1024 => 1024
opcache.jit_max_side_traces => 128 => 128
opcache.jit_prof_threshold => 0.005 => 0.005
opcache.lockfile_path => /tmp => /tmp
opcache.log_verbosity_level => 1 => 1
opcache.max_accelerated_files => 200000 => 200000
opcache.max_file_size => 0 => 0
opcache.max_wasted_percentage => 5 => 5
opcache.memory_consumption => 512 => 512
opcache.opt_debug_level => 0 => 0
opcache.optimization_level => 0x7FFFBFFF => 0x7FFFBFFF
opcache.preferred_memory_model => no value => no value
opcache.preload => /path/to/config/preload.php => //path/to/config/preload.php
opcache.preload_user => user => user
opcache.protect_memory => Off => Off
opcache.record_warnings => Off => Off
opcache.restrict_api => no value => no value
opcache.revalidate_freq => 600 => 600
opcache.revalidate_path => Off => Off
opcache.save_comments => On => On
opcache.use_cwd => On => On
opcache.validate_permission => Off => Off
opcache.validate_root => Off => Off
opcache.validate_timestamps => Off => Off
PHP Version
PHP 8.1.20
Operating System
Debian GNU/Linux 10 (buster) docker container on Amazon Linux 2
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
No source file, test, or minimal reproducer is mentioned. Start by reproducing the PHP 8.1.20 behavior with the supplied OPcache/JIT configuration on the Debian container, comparing JIT enabled and disabled; done means identifying a reproducible trigger and verifying a fix or documented limitation.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- php
- Domain
- compilers, performance
- Issue type
- Bug
- Difficulty
- 5/5
- Estimated time
- Over a week
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 20/100