fix: match requests pool_maxsize to num workers (#6805)

This avoids trashing connections just to immediately re-create them when
`num-worker` > 10. This should provide a pretty solid speedup on beefy
machines.

I'm not attaching any tests because this would be hard to test and if it
doesn't crash with an unknown keyword argument or something it means
it's probably going to be doing what we expect.

src/poetry/installation/executor.py

@@ -60,11 +60,6 @@ class Executor:
         self._dry_run = False
         self._enabled = True
         self._verbose = False
-        self._authenticator = Authenticator(
-            config, self._io, disable_cache=disable_cache
-        )
-        self._chef = Chef(config, self._env)
-        self._chooser = Chooser(pool, self._env, config)
 
         if parallel is None:
             parallel = config.get("installer.parallel", True)
@@ -76,6 +71,12 @@ class Executor:
         else:
             self._max_workers = 1
 
+        self._authenticator = Authenticator(
+            config, self._io, disable_cache=disable_cache, pool_size=self._max_workers
+        )
+        self._chef = Chef(config, self._env)
+        self._chooser = Chooser(pool, self._env, config)
+
         self._executor = ThreadPoolExecutor(max_workers=self._max_workers)
         self._total_operations = 0
         self._executed_operations = 0

src/poetry/utils/authenticator.py

@@ -17,7 +17,7 @@ import requests
 import requests.auth
 import requests.exceptions
 
-from cachecontrol import CacheControl
+from cachecontrol import CacheControlAdapter
 from cachecontrol.caches import FileCache
 from filelock import FileLock
 
@@ -128,6 +128,7 @@ class Authenticator:
         io: IO | None = None,
         cache_id: str | None = None,
         disable_cache: bool = False,
+        pool_size: int = 10,
     ) -> None:
         self._config = config or Config.create()
         self._io = io
@@ -153,6 +154,7 @@ class Authenticator:
         self.get_repository_config_for_url = functools.lru_cache(maxsize=None)(
             self._get_repository_config_for_url
         )
+        self._pool_size = pool_size
 
     def create_session(self) -> requests.Session:
         session = requests.Session()
@@ -160,7 +162,13 @@ class Authenticator:
         if self._cache_control is None:
             return session
 
-        session = CacheControl(sess=session, cache=self._cache_control)
+        adapter = CacheControlAdapter(
+            cache=self._cache_control,
+            pool_maxsize=self._pool_size,
+        )
+        session.mount("http://", adapter)
+        session.mount("https://", adapter)
+
         return session
 
     def get_session(self, url: str | None = None) -> requests.Session: