fix(proxy): make the per-reload credential sync linear in the number of credentials

ProxyConfig.get_credentials runs on every config reload (default 30s) on the
serving event loop. delete_credentials rebuilt the list of all credential names
once per existing credential, and CredentialAccessor.upsert_credentials rescanned
the list once per incoming credential, so both were O(n^2) in the size of the
credentials table. With ~6k rows that is ~10s of blocking per reload: every
request queued and the liveness probe timed out.

Index the current list once and use set membership instead.

litellm/litellm_core_utils/credential_accessor.py

@@ -31,18 +31,19 @@ class CredentialAccessor:
 
     @staticmethod
     def upsert_credentials(credentials: list[CredentialItem]):
-        """Add a credential to the list of credentials."""
+        """Add credentials to the list, replacing any existing entry with the same name in place.
 
-        credential_names: Final = [cred.credential_name for cred in litellm.credential_list]
+        Runs on every config reload with the full DB credential table, so it indexes the
+        current list once instead of rescanning it per credential.
+        """
+        index_by_name: dict[str, int] = {cred.credential_name: i for i, cred in enumerate(litellm.credential_list)}
 
         for credential in credentials:
-            if credential.credential_name in credential_names:
-                # Find and replace the existing credential in the list
-                for i, existing_cred in enumerate(litellm.credential_list):
-                    if existing_cred.credential_name == credential.credential_name:
-                        litellm.credential_list[i] = credential
-                        break
+            existing_index = index_by_name.get(credential.credential_name)
+            if existing_index is not None:
+                litellm.credential_list[existing_index] = credential
             else:
+                index_by_name[credential.credential_name] = len(litellm.credential_list)
                 litellm.credential_list.append(credential)
 
 

litellm/proxy/proxy_server.py

@@ -9660,10 +9660,12 @@ class ProxyConfig:
         combined_list: Final = db_credentials + credential_list
 
         ## DELETE ##
-        idx_to_delete: Final = []
-        for idx, credential in enumerate(litellm.credential_list):
-            if credential.credential_name not in [cred.credential_name for cred in combined_list]:
-                idx_to_delete.append(idx)
+        names_to_keep: Final = {cred.credential_name for cred in combined_list}
+        idx_to_delete: Final = [
+            idx
+            for idx, credential in enumerate(litellm.credential_list)
+            if credential.credential_name not in names_to_keep
+        ]
         for idx in sorted(idx_to_delete, reverse=True):
             litellm.credential_list.pop(idx)
 

tests/test_litellm/litellm_core_utils/test_credential_accessor.py

@@ -0,0 +1,42 @@
+"""CredentialAccessor.upsert_credentials: the per-reload sync of DB credentials into litellm.credential_list."""
+
+import time
+
+import pytest
+
+import litellm
+from litellm.litellm_core_utils.credential_accessor import CredentialAccessor
+from litellm.types.utils import CredentialItem
+
+
+def _cred(name: str, api_key: str) -> CredentialItem:
+    return CredentialItem(credential_name=name, credential_values={"api_key": api_key}, credential_info={})
+
+
+def test_upsert_credentials_replaces_by_name_in_place_and_appends_new(monkeypatch: pytest.MonkeyPatch) -> None:
+    monkeypatch.setattr(litellm, "credential_list", [_cred("a", "old-a"), _cred("b", "old-b"), _cred("c", "old-c")])
+
+    CredentialAccessor.upsert_credentials([_cred("b", "new-b"), _cred("d", "new-d"), _cred("a", "new-a")])
+
+    assert [(c.credential_name, c.credential_values["api_key"]) for c in litellm.credential_list] == [
+        ("a", "new-a"),
+        ("b", "new-b"),
+        ("c", "old-c"),
+        ("d", "new-d"),
+    ]
+
+
+def test_upsert_credentials_scales_linearly_with_credential_count(monkeypatch: pytest.MonkeyPatch) -> None:
+    # The proxy re-upserts every DB credential on each config reload (default every 30s) on the serving
+    # event loop. 20k credentials took ~40s with the previous nested scan; linear takes milliseconds.
+    n = 20_000
+    monkeypatch.setattr(litellm, "credential_list", [_cred(f"cred-{i}", f"k{i}") for i in range(n)])
+    refreshed = [_cred(f"cred-{i}", f"k{i}-v2") for i in range(n)]
+
+    started = time.perf_counter()
+    CredentialAccessor.upsert_credentials(refreshed)
+    elapsed = time.perf_counter() - started
+
+    assert len(litellm.credential_list) == n
+    assert litellm.credential_list[n - 1].credential_values["api_key"] == f"k{n - 1}-v2"
+    assert elapsed < 2.0, f"upsert of {n} credentials took {elapsed:.1f}s; expected linear-time behaviour"

tests/unit/proxy/proxy_server/test_proxy_config.py

@@ -2059,6 +2059,69 @@ def test_ProxyConfig_load_credential_list_invalid_entry_raises():
         pc.load_credential_list({"credential_list": [{"missing_required": True}]})
 
 
+# ---------------------------------------------------------------------------
+# ProxyConfig.delete_credentials
+# ---------------------------------------------------------------------------
+
+
+def _credential_item(name: str) -> "CredentialItem":
+    from litellm.types.utils import CredentialItem
+
+    return CredentialItem(credential_name=name, credential_values={"api_key": f"key-{name}"}, credential_info={})
+
+
+@pytest.mark.asyncio
+async def test_ProxyConfig_delete_credentials_drops_only_names_missing_from_db_and_config(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    pc = ProxyConfig()
+    monkeypatch.setattr(
+        litellm,
+        "credential_list",
+        [_credential_item("db-kept"), _credential_item("stale"), _credential_item("from-config")],
+    )
+
+    async def fake_get_config(*args: object, **kwargs: object) -> dict[str, object]:
+        return {
+            "credential_list": [
+                {"credential_name": "from-config", "credential_values": {"api_key": "cfg"}, "credential_info": {}}
+            ]
+        }
+
+    monkeypatch.setattr(pc, "get_config", fake_get_config)
+
+    await pc.delete_credentials([_credential_item("db-kept")])
+
+    assert [c.credential_name for c in litellm.credential_list] == ["db-kept", "from-config"]
+
+
+@pytest.mark.asyncio
+async def test_ProxyConfig_delete_credentials_scales_linearly_with_credential_count(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    # Runs on the serving event loop every config reload; 20k credentials took ~40s with the previous
+    # nested scan and blocked every request and health probe for that long.
+    import time
+
+    n = 20_000
+    pc = ProxyConfig()
+    monkeypatch.setattr(litellm, "credential_list", [_credential_item(f"cred-{i}") for i in range(n)])
+
+    async def fake_get_config(*args: object, **kwargs: object) -> dict[str, object]:
+        return {}
+
+    monkeypatch.setattr(pc, "get_config", fake_get_config)
+    db_credentials = [_credential_item(f"cred-{i}") for i in range(n) if i != 7]
+
+    started = time.perf_counter()
+    await pc.delete_credentials(db_credentials)
+    elapsed = time.perf_counter() - started
+
+    assert len(litellm.credential_list) == n - 1
+    assert all(c.credential_name != "cred-7" for c in litellm.credential_list)
+    assert elapsed < 2.0, f"delete_credentials over {n} credentials took {elapsed:.1f}s; expected linear-time behaviour"
+
+
 # ---------------------------------------------------------------------------
 # ProxyConfig.parse_search_tools
 # ---------------------------------------------------------------------------