@mpdude this increases readability but I'm not sure it can improve performance, can you give us some stats(prod/dev) ?

👍

@mpdude any chance to make an update ?

First, I don't have any numbers to show whether this improves or degrades performance; see #13948 for a discussion how such a benchmark should look like.

Then, this PR is about "wiring" up fallback MessageCatalogues at runtime. It would make the fix from #14268 unnecessary because the problem described there does not exist in the first place. But it also means that the change from #13981 (in fact, the entire getFallbackContent method) would be dropped because there is no more "fallback content" to dump into the ConfigCache.

Also note that the computeFallbackLocales method is changed slightly. It would previously return all configured fallback locales, excluding the "current" $locale, but including fallback variants from that (en for en_GB, for example). With this PR, it will return all locales that need to be tried should $locale fail, including fallback variants from each of these. Honestly, I don't know if that might be a problem.

Altogether I'm not really sure if this takes us somewhere or what the final destination might be. It's just a feeling that putting smaller and independent MessageCatalogues (i. e. only for one locale; possibly only for one domain) into the cache might be a prerequisite for further deferring catalogue loading (for example, load only catalogue parts for the domain needed in the current trans() request; load catalogues for fallback locales step by step when no translation is found).

That's why it is an RFC :-). I'd be glad to fine-tune the details once we agree that it is worth the effort.

• Performance Some ideas to improve performance of the Translator component #13948

  let's discuss this later :)

• PR [Translation] merge all fallback catalogues messages into current catalo... #13981:

  it's not about caching fallback but is to avoid load fallback messages in prod env so I think it's important and bellow how it should be:

@@ -358,6 +358,20 @@ class Translator implements TranslatorInterface, TranslatorBagInterface
         $cache = new ConfigCache($this->cacheDir.'/catalogue.'.$locale.'.php', $this->debug);
         if ($forceRefresh || !$cache->isFresh()) {
             $this->initializeCatalogue($locale);
+            if (!$this->debug) {
+                $catalogue = $this->catalogues[$locale];
+                // merge all fallback catalogues messages into $catalogue
+                $fallbackCatalogue = $catalogue->getFallbackCatalogue();
+                $messages = $catalogue->all();
+                while ($fallbackCatalogue) {
+                    $messages = array_replace_recursive($fallbackCatalogue->all(), $messages);
+                    $fallbackCatalogue = $fallbackCatalogue->getFallbackCatalogue();
+                }
+                foreach ($messages as $domain => $domainMessages) {
+                    $catalogue->add($domainMessages, $domain);
+                }
+            }
+

• computeFallbackLocales

for BC break reason it should be moved into V3.0 also we need add some test cases that cover these change.

@aitboudad @mpdude What's the status of this PR?

As there is no more activity here, I'm closing this PR. Feel free to reopen a new one if that's still relevant.