ray-project · edoakes · Sep 9, 2025 · Sep 5, 2025 · Sep 5, 2025 · Sep 5, 2025
diff --git a/python/ray/_private/worker.py b/python/ray/_private/worker.py
@@ -2380,7 +2380,6 @@ def is_initialized() -> bool:
     return ray._private.worker.global_worker.connected
 
 
-# TODO(hjiang): Add cgroup path along with [enable_resource_isolation].
 @with_connect_or_shutdown_lock
 def connect(
     node,
@@ -2399,7 +2398,6 @@ def connect(
     worker_launch_time_ms: int = -1,
     worker_launched_time_ms: int = -1,
     debug_source: str = "",
-    enable_resource_isolation: bool = False,
 ):
     """Connect this worker to the raylet, to Plasma, and to GCS.
 
@@ -2428,7 +2426,6 @@ def connect(
             finshes launching. If the worker is not launched by raylet (e.g.,
             driver), this must be -1 (default value).
         debug_source: Source information for `CoreWorker`, used for debugging and informational purpose, rather than functional purpose.
-        enable_resource_isolation: If true, core worker enables resource isolation by adding itself into appropriate cgroup.
     """
     # Do some basic checking to make sure we didn't call ray.init twice.
     error_message = "Perhaps you called ray.init twice by accident?"
@@ -2607,7 +2604,6 @@ def connect(
         worker_launch_time_ms,
         worker_launched_time_ms,
         debug_source,
-        enable_resource_isolation,
     )
 
     if mode == SCRIPT_MODE:

diff --git a/python/ray/_private/workers/default_worker.py b/python/ray/_private/workers/default_worker.py
@@ -271,7 +271,6 @@
         ray_debugger_external=args.ray_debugger_external,
         worker_launch_time_ms=args.worker_launch_time_ms,
         worker_launched_time_ms=worker_launched_time_ms,
-        enable_resource_isolation=args.enable_resource_isolation,
     )
 
     worker = ray._private.worker.global_worker

diff --git a/python/ray/_raylet.pyx b/python/ray/_raylet.pyx
@@ -3002,7 +3002,7 @@ cdef class CoreWorker:
                   local_mode, driver_name,
                   serialized_job_config, metrics_agent_port, runtime_env_hash,
                   startup_token, session_name, cluster_id, entrypoint,
-                  worker_launch_time_ms, worker_launched_time_ms, debug_source, enable_resource_isolation):
+                  worker_launch_time_ms, worker_launched_time_ms, debug_source):
         self.is_local_mode = local_mode
 
         cdef CCoreWorkerOptions options = CCoreWorkerOptions()
@@ -3058,7 +3058,6 @@ cdef class CoreWorker:
         options.worker_launch_time_ms = worker_launch_time_ms
         options.worker_launched_time_ms = worker_launched_time_ms
         options.debug_source = debug_source
-        options.enable_resource_isolation = enable_resource_isolation
         CCoreWorkerProcess.Initialize(options)
 
         self.cgname_to_eventloop_dict = None

diff --git a/python/ray/includes/libcoreworker.pxd b/python/ray/includes/libcoreworker.pxd
@@ -438,7 +438,6 @@ cdef extern from "ray/core_worker/core_worker.h" nogil:
         int64_t worker_launch_time_ms
         int64_t worker_launched_time_ms
         c_string debug_source
-        c_bool enable_resource_isolation
 
     cdef cppclass CCoreWorkerProcess "ray::core::CoreWorkerProcess":
         @staticmethod

diff --git a/src/ray/core_worker/core_worker_options.h b/src/ray/core_worker/core_worker_options.h
@@ -107,8 +107,7 @@ struct CoreWorkerOptions {
         entrypoint(""),
         worker_launch_time_ms(-1),
         worker_launched_time_ms(-1),
-        debug_source(""),
-        enable_resource_isolation(false) {}
+        debug_source("") {}
 
   /// Type of this worker (i.e., DRIVER or WORKER).
   WorkerType worker_type;
@@ -212,10 +211,6 @@ struct CoreWorkerOptions {
   // Source information for `CoreWorker`, used for debugging and informational purpose,
   // rather than functional purpose.
   std::string debug_source;
-
-  // If true, core worker enables resource isolation through cgroupv2 by reserving
-  // resources for ray system processes.
-  bool enable_resource_isolation = false;
 };
 }  // namespace core
 }  // namespace ray
diff --git a/src/ray/core_worker/core_worker_process.cc b/src/ray/core_worker/core_worker_process.cc
@@ -143,13 +143,6 @@ std::shared_ptr<CoreWorker> CoreWorkerProcessImpl::CreateCoreWorker(
       options.worker_type, worker_id, GetProcessJobID(options));
   auto pid = getpid();
 
-  // Move worker process into cgroup on startup.
-  AppProcCgroupMetadata app_cgroup_metadata;
-  app_cgroup_metadata.pid = pid;
-  app_cgroup_metadata.max_memory = kUnlimitedCgroupMemory;
-  GetCgroupSetup(options.enable_resource_isolation)
-      .ApplyCgroupContext(app_cgroup_metadata);
-
   RAY_LOG(DEBUG) << "Creating core worker with debug source: " << options.debug_source;
 
   RAY_LOG(DEBUG).WithField(worker_id) << "Constructing CoreWorker";

diff --git a/src/ray/raylet/BUILD.bazel b/src/ray/raylet/BUILD.bazel
@@ -282,7 +282,6 @@ ray_cc_binary(
         "//src/ray/common:lease",
         "//src/ray/common:ray_config",
         "//src/ray/common:status",
-        "//src/ray/common/cgroup:cgroup_manager",
         "//src/ray/core_worker:metrics",
         "//src/ray/gcs/gcs_client:gcs_client_lib",
         "//src/ray/object_manager:ownership_object_directory",

diff --git a/src/ray/raylet/main.cc b/src/ray/raylet/main.cc
@@ -24,7 +24,6 @@
 #include "gflags/gflags.h"
 #include "nlohmann/json.hpp"
 #include "ray/common/asio/instrumented_io_context.h"
-#include "ray/common/cgroup/cgroup_manager.h"
 #include "ray/common/constants.h"
 #include "ray/common/id.h"
 #include "ray/common/lease/lease.h"
@@ -97,12 +96,6 @@ DEFINE_int64(object_store_memory, -1, "The initial memory of the object store.")
 DEFINE_string(node_name, "", "The user-provided identifier or name for this node.");
 DEFINE_string(session_name, "", "The current Ray session name.");
 DEFINE_string(cluster_id, "", "ID of the cluster, separate from observability.");
-// TODO(hjiang): At the moment only enablement flag is added, I will add other flags for
-// CPU and memory resource reservation in the followup PR.
-DEFINE_bool(enable_resource_isolation,
-            false,
-            "Enable resource isolation through cgroupv2 by reserving resources for ray "
-            "system processes.");
 
 #ifdef __linux__
 DEFINE_string(plasma_directory,
@@ -231,12 +224,8 @@ int main(int argc, char *argv[]) {
   RAY_LOG(INFO) << "Setting cluster ID to: " << cluster_id;
   gflags::ShutDownCommandLineFlags();
 
-  // Get cgroup setup instance and perform necessary resource setup.
-  ray::GetCgroupSetup(FLAGS_enable_resource_isolation);
-
   // Configuration for the node manager.
   ray::raylet::NodeManagerConfig node_manager_config;
-  node_manager_config.enable_resource_isolation = FLAGS_enable_resource_isolation;
 
   absl::flat_hash_map<std::string, double> static_resource_conf;
 
@@ -544,8 +533,7 @@ int main(int argc, char *argv[]) {
         /*starting_worker_timeout_callback=*/
         [&] { cluster_lease_manager->ScheduleAndGrantLeases(); },
         node_manager_config.ray_debugger_external,
-        /*get_time=*/[]() { return absl::Now(); },
-        node_manager_config.enable_resource_isolation);
+        /*get_time=*/[]() { return absl::Now(); });
 
     client_call_manager = std::make_unique<ray::rpc::ClientCallManager>(
         main_service, /*record_stats=*/true);

diff --git a/src/ray/raylet/node_manager.h b/src/ray/raylet/node_manager.h
@@ -115,9 +115,6 @@ struct NodeManagerConfig {
   int max_io_workers;
   // The key-value labels of this node.
   absl::flat_hash_map<std::string, std::string> labels;
-  // If true, core worker enables resource isolation by adding itself into appropriate
-  // cgroup.
-  bool enable_resource_isolation = false;
 };
 
 class NodeManager : public rpc::NodeManagerServiceHandler,

diff --git a/src/ray/raylet/tests/worker_pool_test.cc b/src/ray/raylet/tests/worker_pool_test.cc
@@ -153,8 +153,7 @@ class WorkerPoolMock : public WorkerPool {
             "",
             []() {},
             0,
-            [this]() { return absl::FromUnixMillis(current_time_ms_); },
-            /*enable_resource_isolation=*/false),
+            [this]() { return absl::FromUnixMillis(current_time_ms_); }),
         last_worker_process_(),
         instrumented_io_service_(io_service),
         client_call_manager_(instrumented_io_service_, false),

diff --git a/src/ray/raylet/worker_pool.cc b/src/ray/raylet/worker_pool.cc
@@ -101,8 +101,7 @@ WorkerPool::WorkerPool(instrumented_io_context &io_service,
                        std::string native_library_path,
                        std::function<void()> starting_worker_timeout_callback,
                        int ray_debugger_external,
-                       std::function<absl::Time()> get_time,
-                       bool enable_resource_isolation)
+                       std::function<absl::Time()> get_time)
     : worker_startup_token_counter_(0),
       io_service_(&io_service),
       node_id_(node_id),
@@ -123,8 +122,7 @@ WorkerPool::WorkerPool(instrumented_io_context &io_service,
           std::min(num_prestarted_python_workers, maximum_startup_concurrency_)),
       num_prestart_python_workers(num_prestarted_python_workers),
       periodical_runner_(PeriodicalRunner::Create(io_service)),
-      get_time_(std::move(get_time)),
-      enable_resource_isolation_(enable_resource_isolation) {
+      get_time_(std::move(get_time)) {
   RAY_CHECK_GT(maximum_startup_concurrency_, 0);
   // We need to record so that the metric exists. This way, we report that 0
   // processes have started before a task runs on the node (as opposed to the
@@ -443,12 +441,6 @@ WorkerPool::BuildProcessCommandArgs(const Language &language,
                                   serialized_preload_python_modules);
   }
 
-  // Pass resource isolation flag to python worker.
-  if (language == Language::PYTHON && worker_type == rpc::WorkerType::WORKER) {
-    worker_command_args.emplace_back(absl::StrFormat(
-        "--enable-resource-isolation=%s", enable_resource_isolation_ ? "true" : "false"));
-  }
-
   // We use setproctitle to change python worker process title,
   // causing the process's /proc/PID/environ being empty.
   // Add `SPT_NOENV` env to prevent setproctitle breaking /proc/PID/environ.

diff --git a/src/ray/raylet/worker_pool.h b/src/ray/raylet/worker_pool.h
@@ -304,7 +304,6 @@ class WorkerPool : public WorkerPoolInterface {
   /// \param ray_debugger_external Ray debugger in workers will be started in a way
   /// that they are accessible from outside the node.
   /// \param get_time A callback to get the current time in milliseconds.
-  /// \param enable_resource_isolation If true, core worker enables resource isolation by
   /// adding itself into appropriate cgroup.
   WorkerPool(instrumented_io_context &io_service,
              const NodeID &node_id,
@@ -320,8 +319,7 @@ class WorkerPool : public WorkerPoolInterface {
              std::string native_library_path,
              std::function<void()> starting_worker_timeout_callback,
              int ray_debugger_external,
-             std::function<absl::Time()> get_time,
-             bool enable_resource_isolation);
+             std::function<absl::Time()> get_time);
 
   /// Destructor responsible for freeing a set of workers owned by this class.
   ~WorkerPool() override;
@@ -912,10 +910,6 @@ class WorkerPool : public WorkerPoolInterface {
   int64_t process_failed_pending_registration_ = 0;
   int64_t process_failed_runtime_env_setup_failed_ = 0;
 
-  // If true, core worker enables resource isolation by adding itself into appropriate
-  // cgroup after it is created.
-  bool enable_resource_isolation_ = false;
-
   /// Ray metrics
   ray::stats::Sum ray_metric_num_workers_started_{
       /*name=*/"internal_num_processes_started",