python-telegram-bot · Bibo-Joshi · Jul 31, 2025 · Jul 27, 2025 · Jul 27, 2025 · Jul 27, 2025
diff --git a/changes/unreleased/4882.JpgQAHHnCponMKStbC4JsG.toml b/changes/unreleased/4882.JpgQAHHnCponMKStbC4JsG.toml
@@ -0,0 +1,10 @@
+other = """
+Set the default connection pool size for ``HTTPXRequest`` to 256 to allow more concurrent requests by default. Drop the ``httpx`` parameter ``max_keepalive_connections``. This way, the ``httpx`` default of 20 is used, leading to a smaller number of idle connections in large connection pools.
+
+.. hint::
+   If you manually build the ``HTTPXRequest`` objects, please be aware that these changes also applies to you. Kindly double check your settings. To specify custom limits, you can set them via the parameter ``httpx_kwargs`` of ``HTTPXRequest``. See also  `the httpx documentation <https://www.python-httpx.org/advanced/resource-limits/>`__ for more details on these settings."
+"""
+[[pull_requests]]
+uid = "4882"
+author_uid = "Poolitzer"
+closes_threads = []
diff --git a/src/telegram/_bot.py b/src/telegram/_bot.py
@@ -339,7 +339,11 @@ def __init__(
         self._initialized: bool = False
 
         self._request: tuple[BaseRequest, BaseRequest] = (
-            HTTPXRequest() if get_updates_request is None else get_updates_request,
+            (
+                HTTPXRequest(connection_pool_size=1)
+                if get_updates_request is None
+                else get_updates_request
+            ),
             HTTPXRequest() if request is None else request,
         )
 

diff --git a/src/telegram/request/_httpxrequest.py b/src/telegram/request/_httpxrequest.py
@@ -49,7 +49,13 @@ class HTTPXRequest(BaseRequest):
 
     Args:
         connection_pool_size (:obj:`int`, optional): Number of connections to keep in the
-            connection pool. Defaults to ``1``.
+            connection pool. Defaults to ``256``.
+
+            .. versionchanged:: NEXT.VERSION
+                Set the default to ``256``.
+                Stopped applying to ``httpx.Limits.max_keepalive_connections``. Now only applies to
+                ``httpx.Limits.max_connections``. See `Resource Limits
+                <https://www.python-httpx.org/advanced/resource-limits/>`_
         read_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the maximum
             amount of time (in seconds) to wait for a response from Telegram's server.
             This value is used unless a different value is passed to :meth:`do_request`.
@@ -138,7 +144,7 @@ class HTTPXRequest(BaseRequest):
 
     def __init__(
         self,
-        connection_pool_size: int = 1,
+        connection_pool_size: int = 256,
         read_timeout: Optional[float] = 5.0,
         write_timeout: Optional[float] = 5.0,
         connect_timeout: Optional[float] = 5.0,
@@ -159,7 +165,6 @@ def __init__(
         )
         limits = httpx.Limits(
             max_connections=connection_pool_size,
-            max_keepalive_connections=connection_pool_size,
         )
 
         if http_version not in ("1.1", "2", "2.0"):

diff --git a/tests/ext/test_applicationbuilder.py b/tests/ext/test_applicationbuilder.py
@@ -150,9 +150,7 @@ class Client:
         assert app.bot.local_mode is False
 
         get_updates_client = app.bot._request[0]._client
-        assert get_updates_client.limits == httpx.Limits(
-            max_connections=1, max_keepalive_connections=1
-        )
+        assert get_updates_client.limits == httpx.Limits(max_connections=1)
         assert get_updates_client.proxy is None
         assert get_updates_client.timeout == httpx.Timeout(
             connect=5.0, read=5.0, write=5.0, pool=1.0
@@ -161,7 +159,7 @@ class Client:
         assert not get_updates_client.http2
 
         client = app.bot.request._client
-        assert client.limits == httpx.Limits(max_connections=256, max_keepalive_connections=256)
+        assert client.limits == httpx.Limits(max_connections=256)
         assert client.proxy is None
         assert client.timeout == httpx.Timeout(connect=5.0, read=5.0, write=5.0, pool=1.0)
         assert client.http1 is True
@@ -391,7 +389,7 @@ def init_httpx_request(self_, *args, **kwargs):
         client = app.bot.request._client
 
         assert client.timeout == httpx.Timeout(pool=3, connect=2, read=4, write=5)
-        assert client.limits == httpx.Limits(max_connections=1, max_keepalive_connections=1)
+        assert client.limits == httpx.Limits(max_connections=1)
         assert client.proxy == "proxy"
         assert client.http1 is True
         assert client.http2 is False
@@ -408,7 +406,7 @@ def init_httpx_request(self_, *args, **kwargs):
         client = app.bot._request[0]._client
 
         assert client.timeout == httpx.Timeout(pool=3, connect=2, read=4, write=5)
-        assert client.limits == httpx.Limits(max_connections=1, max_keepalive_connections=1)
+        assert client.limits == httpx.Limits(max_connections=1)
         assert client.proxy == "get_updates_proxy"
         assert client.http1 is True
         assert client.http2 is False

diff --git a/tests/request/test_request.py b/tests/request/test_request.py
@@ -439,9 +439,7 @@ class Client:
         request = HTTPXRequest()
         assert request._client.timeout == httpx.Timeout(connect=5.0, read=5.0, write=5.0, pool=1.0)
         assert request._client.proxy is None
-        assert request._client.limits == httpx.Limits(
-            max_connections=1, max_keepalive_connections=1
-        )
+        assert request._client.limits == httpx.Limits(max_connections=256)
         assert request._client.http1 is True
         assert not request._client.http2
 
@@ -454,9 +452,7 @@ class Client:
             pool_timeout=46,
         )
         assert request._client.proxy == "proxy"
-        assert request._client.limits == httpx.Limits(
-            max_connections=42, max_keepalive_connections=42
-        )
+        assert request._client.limits == httpx.Limits(max_connections=42)
         assert request._client.timeout == httpx.Timeout(connect=43, read=44, write=45, pool=46)
 
     async def test_multiple_inits_and_shutdowns(self, monkeypatch):