… disabled (bastnic)This PR was merged into the 5.4 branch.Discussion----------[FrameworkBundle] enable metadata cache when annotation is disabled| Q             | A| ------------- | ---| Branch?       | 5.4| Bug fix?      | yes| New feature?  | no| Deprecations? | no| Tickets       | Fix #... <!-- prefix each issue number with "Fix #", no need to create an issue if none exists, explain below instead -->| License       | MIT| Doc PR        | symfony/symfony-docs#... <!-- required for new features -->When using Annotations, annotations are cached at `AnnotationLoader` level.Which is cleared when entities are changed. So the dev experience is optimal.```[ClassMetadataFactory.php](vendor/symfony/serializer/Mapping/Factory/ClassMetadataFactory.php") on line 51:[Symfony\Component\Serializer\Mapping\Loader\LoaderChain](vendor/symfony/serializer/Mapping/Loader/LoaderChain.php&line=28#line28) {#543 ▼  -loaders: array:1 [▼    0 => [Symfony\Component\Serializer\Mapping\Loader\AnnotationLoader](vendor/symfony/serializer/Mapping/Loader/AnnotationLoader.php&line=33#line33) {#544 ▼      -reader: [Doctrine\Common\Annotations\PsrCachedReader](vendor/doctrine/annotations/lib/Doctrine/Common/Annotations/PsrCachedReader.php&line=22#line22) {#262 ▼        -delegate: [Doctrine\Common\Annotations\AnnotationReader](vendor/doctrine/annotations/lib/Doctrine/Common/Annotations/AnnotationReader.php&line=20#line20) {#263 ▶}        -cache: [Symfony\Component\Cache\Adapter\PhpArrayAdapter](vendor/symfony/cache/Adapter/PhpArrayAdapter.php&line=32#line32) {#277 ▶}        -debug: true        -loadedAnnotations: array:14 [▶]        -loadedFilemtimes: array:4 [▶]      }    }  ]}```When using yaml files, there is no cache at the loader level so I added in the past the same cache as for the prod env, as the metadata are effectively cleared when using only yaml config files.#35109The regression introduced by my patch is for people that do not use mapping files but use annotations.#41961But now, we are in the opposite situation: no cache for people using mapping files but not annotations.On a current project it means loading 83 yaml files for each dev requests. It's not good at all.A simple local fix is to add that in a dev services files.```yamlserializer.mapping.cache_class_metadata_factory:    class: 'Symfony\Component\Serializer\Mapping\Factory\CacheClassMetadataFactory'    decorates: 'serializer.mapping.class_metadata_factory'    arguments: ['`@serializer`.mapping.cache_class_metadata_factory.inner', '`@serializer`.mapping.cache.symfony']```![image](https://user-images.githubusercontent.com/84887/224833940-b8e7ad72-e7f6-44e7-a924-0b20f2f0cdae.png)A solution in Symfony could be:1/ only yaml/xml mapping files (`enable_annotations: false`) : cache like prod => that what I did in this PR, as it fixes the current perf regressions on my different projects. There is no cache on yaml/xml file as soon as annotation is enabled (which is the default)2/ add a cache at reader level for yaml/xml loader3/ add a cache cleaner at metadata level when annotation are enabledCommits-------1773dff [FrameworkBundle] enable metadata cache when annotation is disabled