From 481545b397572ff460f4eee747df2066cde9501c Mon Sep 17 00:00:00 2001
From: Ryan Li <ryanli@ryanli.org>
Date: Tue, 14 Oct 2025 14:52:21 +0800
Subject: [PATCH] scheduler.py: Update the name of the default scheduler.
 (#26758)

Signed-off-by: Ryan Li <ryanli@ryanli.org>
---
 vllm/config/scheduler.py | 12 ++++++------
 vllm/engine/arg_utils.py |  5 -----
 2 files changed, 6 insertions(+), 11 deletions(-)

diff --git a/vllm/config/scheduler.py b/vllm/config/scheduler.py
index 061aa4d4a4f5b..d5eb077309238 100644
--- a/vllm/config/scheduler.py
+++ b/vllm/config/scheduler.py
@@ -131,12 +131,12 @@ class SchedulerConfig:
     some image tokens can be scheduled (like TTTTIIIII, leaving IIIII),
     it will be scheduled as TTTT in one step and IIIIIIIIII in the next."""
 
-    # scheduler class or path. "vllm.core.scheduler.Scheduler" (default)
-    # or "mod.custom_class".
-    scheduler_cls: str | type[object] = "vllm.core.scheduler.Scheduler"
-    """The scheduler class to use. "vllm.core.scheduler.Scheduler" is the
-    default scheduler. Can be a class directly or the path to a class of form
-    "mod.custom_class"."""
+    # scheduler class or path. "vllm.v1.core.sched.scheduler.Scheduler"
+    # (default) or "mod.custom_class".
+    scheduler_cls: str | type[object] = "vllm.v1.core.sched.scheduler.Scheduler"
+    """The scheduler class to use. "vllm.v1.core.sched.scheduler.Scheduler" is
+    the default scheduler. Can be a class directly or the path to a class of
+    form "mod.custom_class"."""
 
     disable_hybrid_kv_cache_manager: bool = False
     """If set to True, KV cache manager will allocate the same size of KV cache
diff --git a/vllm/engine/arg_utils.py b/vllm/engine/arg_utils.py
index 09c8b4ca02c57..14be20b3a5d45 100644
--- a/vllm/engine/arg_utils.py
+++ b/vllm/engine/arg_utils.py
@@ -1742,11 +1742,6 @@ class EngineArgs:
                 self.enable_prefix_caching = incremental_prefill_supported
                 logger.info("(%s) prefix caching by default", action)
 
-        # V1 should use the new scheduler by default.
-        # Swap it only if this arg is set to the original V0 default
-        if self.scheduler_cls == EngineArgs.scheduler_cls:
-            self.scheduler_cls = "vllm.v1.core.sched.scheduler.Scheduler"
-
         # When no user override, set the default values based on the usage
         # context.
         # Use different default values for different hardware.