config: the KV-cache configurator reads the bags (#34096)

test/registered/dcp/test_dcp_layout_unit.py

@@ -191,25 +191,20 @@ class TestGetDcpLens(CustomTestCase):
         )
         allocators = {}
 
-        # The configurator's bag reads (disaggregation_mode / page_size /
-        # enable_hisparse) come from the published context; the per-iteration
-        # dcp_size stays on the injected instance stand-in.
-        self._sa_override = rc.get_context().override_server_args(
+        # The configurator's own inputs are published leaves now, so the case
+        # publishes them once. The DCP *scale* is not one of them: the allocator
+        # widens from the live get_parallel().attn_dcp_size, which the per-size
+        # override inside the loop drives.
+        override = rc.get_context().override_server_args(
             disaggregation_mode="null",
             page_size=physical_page_size,
             enable_hisparse=False,
         )
-        self._sa_override.install()
-        self.addCleanup(self._sa_override.restore)
-
+        override.install()
+        self.addCleanup(override.restore)
         for dcp_size in (1, 4):
             configurator = SimpleNamespace(
-                server_args=SimpleNamespace(
-                    disaggregation_mode="null",
-                    enable_hisparse=False,
-                    page_size=physical_page_size,
-                    dcp_size=dcp_size,
-                ),
+                server_args=SimpleNamespace(),
                 hybrid_gdn_config=None,
                 is_hybrid_swa=False,
                 kv_cache_dtype=torch.bfloat16,