[misc] Add PD service discovery support in router (#7361)

sgl-router/Cargo.toml

@@ -35,6 +35,7 @@ metrics = "0.24.2"
 metrics-exporter-prometheus = "0.17.0"
 # Added for request tracing
 uuid = { version = "1.10", features = ["v4", "serde"] }
+thiserror = "2.0.12"
 [profile.release]
 lto = "thin"
 codegen-units = 1

sgl-router/README.md

@@ -95,38 +95,217 @@ python -m sglang_router.launch_router \
 
 ### Kubernetes Service Discovery
 
-SGL Router supports automatic service discovery for worker nodes in Kubernetes environments. When enabled, the router will automatically:
+SGL Router supports automatic service discovery for worker nodes in Kubernetes environments. This feature works with both regular (single-server) routing and PD (Prefill-Decode) routing modes. When enabled, the router will automatically:
 
 - Discover and add worker pods with matching labels
 - Remove unhealthy or deleted worker pods
 - Dynamically adjust the worker pool based on pod health and availability
+- For PD mode: distinguish between prefill and decode servers based on labels
 
-#### Command Line Usage
+#### Regular Mode Service Discovery
+
+For traditional single-server routing:
 
 ```bash
 python -m sglang_router.launch_router \
     --service-discovery \
     --selector app=sglang-worker role=inference \
-    --service-discovery-port 8000 \
     --service-discovery-namespace default
 ```
 
+#### PD Mode Service Discovery
+
+For PD (Prefill-Decode) disaggregated routing, service discovery can automatically discover and classify pods as either prefill or decode servers based on their labels:
+
+```bash
+python -m sglang_router.launch_router \
+    --pd-disaggregation \
+    --policy cache_aware \
+    --service-discovery \
+    --prefill-selector app=sglang component=prefill \
+    --decode-selector app=sglang component=decode \
+    --service-discovery-namespace sglang-system
+```
+
+You can also specify initial prefill and decode servers and let service discovery add more:
+
+```bash
+python -m sglang_router.launch_router \
+    --pd-disaggregation \
+    --policy cache_aware \
+    --prefill http://prefill-1:8000 8001 \
+    --decode http://decode-1:8000 \
+    --service-discovery \
+    --prefill-selector app=sglang component=prefill \
+    --decode-selector app=sglang component=decode \
+    --service-discovery-namespace sglang-system
+```
+
+#### Kubernetes Pod Configuration for PD Mode
+
+When using PD service discovery, your Kubernetes pods need specific labels to be classified as prefill or decode servers:
+
+**Prefill Server Pod:**
+```yaml
+apiVersion: v1
+kind: Pod
+metadata:
+  name: sglang-prefill-1
+  labels:
+    app: sglang
+    component: prefill
+  annotations:
+    sglang.ai/bootstrap-port: "9001"  # Optional: Bootstrap port for Mooncake prefill coordination
+spec:
+  containers:
+  - name: sglang
+    image: lmsys/sglang:latest
+    ports:
+    - containerPort: 8000  # Main API port
+    - containerPort: 9001  # Optional: Bootstrap coordination port
+    # ... rest of configuration
+```
+
+**Decode Server Pod:**
+```yaml
+apiVersion: v1
+kind: Pod
+metadata:
+  name: sglang-decode-1
+  labels:
+    app: sglang
+    component: decode
+spec:
+  containers:
+  - name: sglang
+    image: lmsys/sglang:latest
+    ports:
+    - containerPort: 8000  # Main API port
+    # ... rest of configuration
+```
+
+**Key Requirements:**
+- Prefill pods must have labels matching your `--prefill-selector`
+- Decode pods must have labels matching your `--decode-selector`
+- Prefill pods can optionally include bootstrap port in annotations using `sglang.ai/bootstrap-port` (defaults to None if not specified)
+
 #### Service Discovery Arguments
 
+**General Arguments:**
 - `--service-discovery`: Enable Kubernetes service discovery feature
-- `--selector`: One or more label key-value pairs for pod selection (format: key1=value1 key2=value2)
+- `--service-discovery-port`: Port to use when generating worker URLs (default: 8000)
-- `--service-discovery-port`: Port to use when generating worker URLs (default: 80)
 - `--service-discovery-namespace`: Optional. Kubernetes namespace to watch for pods. If not provided, watches all namespaces (requires cluster-wide permissions)
+- `--selector`: One or more label key-value pairs for pod selection in regular mode (format: key1=value1 key2=value2)
+
+**PD Mode Arguments:**
+- `--pd-disaggregation`: Enable PD (Prefill-Decode) disaggregated mode
+- `--prefill`: Specify initial prefill server URL and bootstrap port (format: URL BOOTSTRAP_PORT, can be used multiple times)
+- `--decode`: Specify initial decode server URL (can be used multiple times)
+- `--prefill-selector`: Label selector for prefill server pods in PD mode (format: key1=value1 key2=value2)
+- `--decode-selector`: Label selector for decode server pods in PD mode (format: key1=value1 key2=value2)
+- `--policy`: Routing policy (cache_aware, random, power_of_two - note: power_of_two only works in PD mode)
+
+**Notes:**
+- Bootstrap port annotation is automatically set to `sglang.ai/bootstrap-port` for Mooncake deployments
+- Advanced cache tuning parameters use sensible defaults and are not exposed via CLI
 
 #### RBAC Requirements
 
 When using service discovery, you must configure proper Kubernetes RBAC permissions:
 
-- **If using namespace-scoped discovery** (with `--service-discovery-namespace`):
+**Namespace-scoped (recommended):**
-  Set up a ServiceAccount, Role, and RoleBinding
+```yaml
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: sglang-router
+  namespace: sglang-system
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: Role
+metadata:
+  namespace: sglang-system
+  name: sglang-router
+rules:
+- apiGroups: [""]
+  resources: ["pods"]
+  verbs: ["get", "list", "watch"]
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: RoleBinding
+metadata:
+  name: sglang-router
+  namespace: sglang-system
+subjects:
+- kind: ServiceAccount
+  name: sglang-router
+  namespace: sglang-system
+roleRef:
+  kind: Role
+  name: sglang-router
+  apiGroup: rbac.authorization.k8s.io
+```
 
-- **If watching all namespaces** (without specifying namespace):
+**Cluster-wide (if watching all namespaces):**
-  Set up a ServiceAccount, ClusterRole, and ClusterRoleBinding with permissions to list/watch pods at the cluster level
+```yaml
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: sglang-router
+  namespace: sglang-system
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRole
+metadata:
+  name: sglang-router
+rules:
+- apiGroups: [""]
+  resources: ["pods"]
+  verbs: ["get", "list", "watch"]
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRoleBinding
+metadata:
+  name: sglang-router
+subjects:
+- kind: ServiceAccount
+  name: sglang-router
+  namespace: sglang-system
+roleRef:
+  kind: ClusterRole
+  name: sglang-router
+  apiGroup: rbac.authorization.k8s.io
+```
+
+#### Complete Example: PD Mode with Service Discovery
+
+Here's a complete example of running SGLang Router with PD mode and service discovery:
+
+```bash
+# Start the router with PD mode and automatic prefill/decode discovery
+python -m sglang_router.launch_router \
+    --pd-disaggregation \
+    --policy cache_aware \
+    --service-discovery \
+    --prefill-selector app=sglang component=prefill environment=production \
+    --decode-selector app=sglang component=decode environment=production \
+    --service-discovery-namespace production \
+    --host 0.0.0.0 \
+    --port 8080 \
+    --prometheus-host 0.0.0.0 \
+    --prometheus-port 9090
+```
+
+This setup will:
+1. Enable PD (Prefill-Decode) disaggregated routing mode with automatic pod classification
+2. Watch for pods in the `production` namespace
+3. Automatically add prefill servers with labels `app=sglang`, `component=prefill`, `environment=production`
+4. Automatically add decode servers with labels `app=sglang`, `component=decode`, `environment=production`
+5. Extract bootstrap ports from the `sglang.ai/bootstrap-port` annotation on prefill pods
+6. Use cache-aware load balancing for optimal performance
+7. Expose the router API on port 8080 and metrics on port 9090
+
+**Note:** In PD mode with service discovery, pods MUST match either the prefill or decode selector to be added. Pods that don't match either selector are ignored.
 
 ### Troubleshooting
 

sgl-router/py_src/sglang_router/launch_router.py

@@ -32,7 +32,7 @@ class RouterArgs:
     port: int = 30000
 
     # PD-specific configuration
-    pd_disaggregated: bool = False  # Enable PD disaggregated mode
+    pd_disaggregation: bool = False  # Enable PD disaggregated mode
     prefill_urls: List[tuple] = dataclasses.field(
         default_factory=list
     )  # List of (url, bootstrap_port)
@@ -55,6 +55,10 @@ class RouterArgs:
     selector: Dict[str, str] = dataclasses.field(default_factory=dict)
     service_discovery_port: int = 80
     service_discovery_namespace: Optional[str] = None
+    # PD service discovery configuration
+    prefill_selector: Dict[str, str] = dataclasses.field(default_factory=dict)
+    decode_selector: Dict[str, str] = dataclasses.field(default_factory=dict)
+    bootstrap_port_annotation: str = "sglang.ai/bootstrap-port"
     # Prometheus configuration
     prometheus_port: Optional[int] = None
     prometheus_host: Optional[str] = None
@@ -108,7 +112,7 @@ class RouterArgs:
 
         # PD-specific arguments
         parser.add_argument(
-            f"--{prefix}pd-disaggregated",
+            f"--{prefix}pd-disaggregation",
             action="store_true",
             help="Enable PD (Prefill-Decode) disaggregated mode",
         )
@@ -207,6 +211,18 @@ class RouterArgs:
             type=str,
             help="Kubernetes namespace to watch for pods. If not provided, watches all namespaces (requires cluster-wide permissions)",
         )
+        parser.add_argument(
+            f"--{prefix}prefill-selector",
+            type=str,
+            nargs="+",
+            help="Label selector for prefill server pods in PD mode (format: key1=value1 key2=value2)",
+        )
+        parser.add_argument(
+            f"--{prefix}decode-selector",
+            type=str,
+            nargs="+",
+            help="Label selector for decode server pods in PD mode (format: key1=value1 key2=value2)",
+        )
         # Prometheus configuration
         parser.add_argument(
             f"--{prefix}prometheus-port",
@@ -243,7 +259,7 @@ class RouterArgs:
             worker_urls=worker_urls,
             host=args.host,
             port=args.port,
-            pd_disaggregated=getattr(args, f"{prefix}pd_disaggregated", False),
+            pd_disaggregation=getattr(args, f"{prefix}pd_disaggregation", False),
             prefill_urls=prefill_urls,
             decode_urls=decode_urls,
             policy=getattr(args, f"{prefix}policy"),
@@ -267,6 +283,13 @@ class RouterArgs:
             service_discovery_namespace=getattr(
                 args, f"{prefix}service_discovery_namespace", None
             ),
+            prefill_selector=cls._parse_selector(
+                getattr(args, f"{prefix}prefill_selector", None)
+            ),
+            decode_selector=cls._parse_selector(
+                getattr(args, f"{prefix}decode_selector", None)
+            ),
+            bootstrap_port_annotation="sglang.ai/bootstrap-port",  # Mooncake-specific annotation
             prometheus_port=getattr(args, f"{prefix}prometheus_port", None),
             prometheus_host=getattr(args, f"{prefix}prometheus_host", None),
         )
@@ -355,17 +378,20 @@ def launch_router(args: argparse.Namespace) -> Optional[Router]:
             router_args = args
 
         # Validate configuration based on mode
-        if router_args.pd_disaggregated:
+        if router_args.pd_disaggregation:
-            # Validate PD configuration
+            # Validate PD configuration - skip URL requirements if using service discovery
+            if not router_args.service_discovery:
                 if not router_args.prefill_urls:
-                raise ValueError("PD disaggregated mode requires --prefill")
+                    raise ValueError("PD disaggregation mode requires --prefill")
                 if not router_args.decode_urls:
-                raise ValueError("PD disaggregated mode requires --decode")
+                    raise ValueError("PD disaggregation mode requires --decode")
 
         # Create router with unified constructor
         router = Router(
             worker_urls=(
-                router_args.worker_urls if not router_args.pd_disaggregated else []
+                []
+                if router_args.service_discovery or router_args.pd_disaggregation
+                else router_args.worker_urls
             ),
             host=router_args.host,
             port=router_args.port,
@@ -384,14 +410,16 @@ def launch_router(args: argparse.Namespace) -> Optional[Router]:
             selector=router_args.selector,
             service_discovery_port=router_args.service_discovery_port,
             service_discovery_namespace=router_args.service_discovery_namespace,
+            prefill_selector=router_args.prefill_selector,
+            decode_selector=router_args.decode_selector,
             prometheus_port=router_args.prometheus_port,
             prometheus_host=router_args.prometheus_host,
-            pd_disaggregated=router_args.pd_disaggregated,
+            pd_disaggregation=router_args.pd_disaggregation,
             prefill_urls=(
-                router_args.prefill_urls if router_args.pd_disaggregated else None
+                router_args.prefill_urls if router_args.pd_disaggregation else None
             ),
             decode_urls=(
-                router_args.decode_urls if router_args.pd_disaggregated else None
+                router_args.decode_urls if router_args.pd_disaggregation else None
             ),
         )
 
@@ -425,7 +453,7 @@ Examples:
   python -m sglang_router.launch_router --worker-urls http://worker1:8000 http://worker2:8000
 
   # PD disaggregated mode
-  python -m sglang_router.launch_router --pd-disaggregated \\
+  python -m sglang_router.launch_router --pd-disaggregation \\
     --prefill http://prefill1:8000 9000 --prefill http://prefill2:8000 none \\
     --decode http://decode1:8001 --decode http://decode2:8001 \\
     --policy cache_aware

sgl-router/py_src/sglang_router/router.py

@@ -41,9 +41,13 @@ class Router:
             worker URLs using this port. Default: 80
         service_discovery_namespace: Kubernetes namespace to watch for pods. If not provided,
             watches pods across all namespaces (requires cluster-wide permissions). Default: None
+        prefill_selector: Dictionary mapping of label keys to values for Kubernetes pod selection
+            for prefill servers (PD mode only). Default: {}
+        decode_selector: Dictionary mapping of label keys to values for Kubernetes pod selection
+            for decode servers (PD mode only). Default: {}
         prometheus_port: Port to expose Prometheus metrics. Default: None
         prometheus_host: Host address to bind the Prometheus metrics server. Default: None
-        pd_disaggregated: Enable PD (Prefill-Decode) disaggregated mode. Default: False
+        pd_disaggregation: Enable PD (Prefill-Decode) disaggregated mode. Default: False
         prefill_urls: List of (url, bootstrap_port) tuples for prefill servers (PD mode only)
         decode_urls: List of URLs for decode servers (PD mode only)
     """
@@ -68,14 +72,20 @@ class Router:
         selector: Dict[str, str] = None,
         service_discovery_port: int = 80,
         service_discovery_namespace: Optional[str] = None,
+        prefill_selector: Dict[str, str] = None,
+        decode_selector: Dict[str, str] = None,
         prometheus_port: Optional[int] = None,
         prometheus_host: Optional[str] = None,
-        pd_disaggregated: bool = False,
+        pd_disaggregation: bool = False,
         prefill_urls: Optional[List[tuple]] = None,
         decode_urls: Optional[List[str]] = None,
     ):
         if selector is None:
             selector = {}
+        if prefill_selector is None:
+            prefill_selector = {}
+        if decode_selector is None:
+            decode_selector = {}
 
         self._router = _Router(
             worker_urls=worker_urls,
@@ -96,9 +106,11 @@ class Router:
             selector=selector,
             service_discovery_port=service_discovery_port,
             service_discovery_namespace=service_discovery_namespace,
+            prefill_selector=prefill_selector,
+            decode_selector=decode_selector,
             prometheus_port=prometheus_port,
             prometheus_host=prometheus_host,
-            pd_disaggregated=pd_disaggregated,
+            pd_disaggregation=pd_disaggregation,
             prefill_urls=prefill_urls,
             decode_urls=decode_urls,
         )

sgl-router/py_test/test_launch_router.py

@@ -45,7 +45,7 @@ class TestLaunchRouter(unittest.TestCase):
             prometheus_port=None,
             prometheus_host=None,
             # PD-specific attributes
-            pd_disaggregated=False,
+            pd_disaggregation=False,
             prefill=None,
             decode=None,
             # Keep worker_urls for regular mode
@@ -119,7 +119,7 @@ class TestLaunchRouter(unittest.TestCase):
         # Test RouterArgs parsing for PD mode
         # Simulate the parsed args structure from argparse with action="append"
         args = self.create_router_args(
-            pd_disaggregated=True,
+            pd_disaggregation=True,
             policy="power_of_two",  # PowerOfTwo is only valid in PD mode
             prefill=[
                 ["http://prefill1:8080", "9000"],
@@ -133,7 +133,7 @@ class TestLaunchRouter(unittest.TestCase):
         )
 
         router_args = RouterArgs.from_cli_args(args)
-        self.assertTrue(router_args.pd_disaggregated)
+        self.assertTrue(router_args.pd_disaggregation)
         self.assertEqual(router_args.policy, "power_of_two")
         self.assertEqual(len(router_args.prefill_urls), 2)
         self.assertEqual(len(router_args.decode_urls), 2)
@@ -147,7 +147,7 @@ class TestLaunchRouter(unittest.TestCase):
         # Test Router creation in PD mode
         router = Router(
             worker_urls=[],  # Empty for PD mode
-            pd_disaggregated=True,
+            pd_disaggregation=True,
             prefill_urls=[
                 ("http://prefill1:8080", 9000),
                 ("http://prefill2:8080", None),
@@ -165,7 +165,7 @@ class TestLaunchRouter(unittest.TestCase):
 
         # Test 1: PowerOfTwo is only valid in PD mode
         args = self.create_router_args(
-            pd_disaggregated=False,
+            pd_disaggregation=False,
             policy="power_of_two",
             worker_urls=["http://localhost:8000"],
         )
@@ -180,7 +180,7 @@ class TestLaunchRouter(unittest.TestCase):
 
         # Test 2: RoundRobin is not valid in PD mode
         args = self.create_router_args(
-            pd_disaggregated=True,
+            pd_disaggregation=True,
             policy="round_robin",
             prefill=[["http://prefill1:8080", "9000"]],
             decode=[["http://decode1:8081"]],
@@ -198,7 +198,7 @@ class TestLaunchRouter(unittest.TestCase):
         # Test 3: Valid combinations should not raise errors
         # Regular mode with RoundRobin
         args = self.create_router_args(
-            pd_disaggregated=False,
+            pd_disaggregation=False,
             policy="round_robin",
             worker_urls=["http://localhost:8000"],
         )
@@ -206,7 +206,7 @@ class TestLaunchRouter(unittest.TestCase):
 
         # PD mode with PowerOfTwo
         args = self.create_router_args(
-            pd_disaggregated=True,
+            pd_disaggregation=True,
             policy="power_of_two",
             prefill=[["http://prefill1:8080", "9000"]],
             decode=[["http://decode1:8081"]],
@@ -214,6 +214,79 @@ class TestLaunchRouter(unittest.TestCase):
         )
         # This should not raise (though it may fail to connect)
 
+    def test_pd_service_discovery_args_parsing(self):
+        """Test PD service discovery CLI argument parsing."""
+        import argparse
+
+        from sglang_router.launch_router import RouterArgs
+
+        parser = argparse.ArgumentParser()
+        RouterArgs.add_cli_args(parser)
+
+        args = parser.parse_args(
+            [
+                "--pd-disaggregation",
+                "--service-discovery",
+                "--prefill-selector",
+                "app=sglang",
+                "component=prefill",
+                "--decode-selector",
+                "app=sglang",
+                "component=decode",
+                "--service-discovery-port",
+                "8000",
+                "--service-discovery-namespace",
+                "production",
+                "--policy",
+                "cache_aware",
+            ]
+        )
+
+        router_args = RouterArgs.from_cli_args(args)
+
+        self.assertTrue(router_args.pd_disaggregation)
+        self.assertTrue(router_args.service_discovery)
+        self.assertEqual(
+            router_args.prefill_selector, {"app": "sglang", "component": "prefill"}
+        )
+        self.assertEqual(
+            router_args.decode_selector, {"app": "sglang", "component": "decode"}
+        )
+        self.assertEqual(router_args.service_discovery_port, 8000)
+        self.assertEqual(router_args.service_discovery_namespace, "production")
+
+    def test_regular_service_discovery_args_parsing(self):
+        """Test regular mode service discovery CLI argument parsing."""
+        import argparse
+
+        from sglang_router.launch_router import RouterArgs
+
+        parser = argparse.ArgumentParser()
+        RouterArgs.add_cli_args(parser)
+
+        args = parser.parse_args(
+            [
+                "--service-discovery",
+                "--selector",
+                "app=sglang-worker",
+                "environment=staging",
+                "--service-discovery-port",
+                "8000",
+                "--policy",
+                "round_robin",
+            ]
+        )
+
+        router_args = RouterArgs.from_cli_args(args)
+
+        self.assertFalse(router_args.pd_disaggregation)
+        self.assertTrue(router_args.service_discovery)
+        self.assertEqual(
+            router_args.selector, {"app": "sglang-worker", "environment": "staging"}
+        )
+        self.assertEqual(router_args.prefill_selector, {})
+        self.assertEqual(router_args.decode_selector, {})
+
 
 if __name__ == "__main__":
     unittest.main()

sgl-router/src/lib.rs

@@ -42,12 +42,16 @@ struct Router {
     selector: HashMap<String, String>,
     service_discovery_port: u16,
     service_discovery_namespace: Option<String>,
+    // PD service discovery fields
+    prefill_selector: HashMap<String, String>,
+    decode_selector: HashMap<String, String>,
+    bootstrap_port_annotation: String,
     prometheus_port: Option<u16>,
     prometheus_host: Option<String>,
     request_timeout_secs: u64,
     // PD mode flag
-    pd_disaggregated: bool,
+    pd_disaggregation: bool,
-    // PD-specific fields (only used when pd_disaggregated is true)
+    // PD-specific fields (only used when pd_disaggregation is true)
     prefill_urls: Option<Vec<(String, Option<u16>)>>,
     decode_urls: Option<Vec<String>>,
 }
@@ -74,10 +78,13 @@ impl Router {
         selector = HashMap::new(),
         service_discovery_port = 80,
         service_discovery_namespace = None,
+        prefill_selector = HashMap::new(),
+        decode_selector = HashMap::new(),
+        bootstrap_port_annotation = String::from("sglang.ai/bootstrap-port"),
         prometheus_port = None,
         prometheus_host = None,
         request_timeout_secs = 600,  // Add configurable request timeout
-        pd_disaggregated = false,  // New flag for PD mode
+        pd_disaggregation = false,  // New flag for PD mode
         prefill_urls = None,
         decode_urls = None
     ))]
@@ -100,10 +107,13 @@ impl Router {
         selector: HashMap<String, String>,
         service_discovery_port: u16,
         service_discovery_namespace: Option<String>,
+        prefill_selector: HashMap<String, String>,
+        decode_selector: HashMap<String, String>,
+        bootstrap_port_annotation: String,
         prometheus_port: Option<u16>,
         prometheus_host: Option<String>,
         request_timeout_secs: u64,
-        pd_disaggregated: bool,
+        pd_disaggregation: bool,
         prefill_urls: Option<Vec<(String, Option<u16>)>>,
         decode_urls: Option<Vec<String>>,
     ) -> PyResult<Self> {
@@ -126,17 +136,20 @@ impl Router {
             selector,
             service_discovery_port,
             service_discovery_namespace,
+            prefill_selector,
+            decode_selector,
+            bootstrap_port_annotation,
             prometheus_port,
             prometheus_host,
             request_timeout_secs,
-            pd_disaggregated,
+            pd_disaggregation,
             prefill_urls,
             decode_urls,
         })
     }
 
     fn start(&self) -> PyResult<()> {
-        let policy_config = if self.pd_disaggregated {
+        let policy_config = if self.pd_disaggregation {
             // PD mode - map PolicyType to PDSelectionPolicy
             let pd_selection_policy = match &self.policy {
                 PolicyType::Random => pd_types::PDSelectionPolicy::Random,
@@ -207,6 +220,11 @@ impl Router {
                 check_interval: std::time::Duration::from_secs(60),
                 port: self.service_discovery_port,
                 namespace: self.service_discovery_namespace.clone(),
+                // PD mode configuration
+                pd_mode: self.pd_disaggregation,
+                prefill_selector: self.prefill_selector.clone(),
+                decode_selector: self.decode_selector.clone(),
+                bootstrap_port_annotation: self.bootstrap_port_annotation.clone(),
             })
         } else {
             None

sgl-router/src/pd_router.rs

@@ -1,7 +1,9 @@
 // PD (Prefill-Decode) Router Implementation
 // This module handles routing for disaggregated prefill-decode systems
 
-use crate::pd_types::{Bootstrap, ChatReqInput, EngineInfo, GenerateReqInput, PDSelectionPolicy};
+use crate::pd_types::{
+    Bootstrap, ChatReqInput, EngineInfo, GenerateReqInput, PDRouterError, PDSelectionPolicy,
+};
 use crate::tree::Tree;
 use actix_web::http::header::{HeaderValue, CONTENT_TYPE};
 use actix_web::{HttpRequest, HttpResponse};
@@ -65,12 +67,145 @@ impl Drop for LoadGuard<'_> {
 }
 
 impl PDRouter {
-    // TODO: Add methods for dynamic worker management to support /register endpoint:
+    // Dynamic worker management methods for service discovery
-    // - add_prefill_server(url: String, bootstrap_port: Option<u16>)
+    pub async fn add_prefill_server(
-    // - add_decode_server(url: String)
+        &self,
-    // - remove_prefill_server(url: &str)
+        url: String,
-    // - remove_decode_server(url: &str)
+        bootstrap_port: Option<u16>,
-    // These methods will be used when service discovery is implemented for PD mode
+    ) -> Result<String, PDRouterError> {
+        // Create EngineInfo for the new prefill server
+        let engine_info = EngineInfo::new_prefill(url.clone(), bootstrap_port);
+
+        // Wait for the new server to be healthy
+        crate::router::Router::wait_for_healthy_workers(
+            &[url.clone()],
+            self.timeout_secs,
+            self.interval_secs,
+        )
+        .map_err(|_| PDRouterError::HealthCheckFailed { url: url.clone() })?;
+
+        // Add to prefill workers list
+        let mut workers = self
+            .prefill_workers
+            .write()
+            .map_err(|_| PDRouterError::LockError {
+                operation: "prefill_workers write".to_string(),
+            })?;
+
+        // Check if already exists
+        if workers.iter().any(|w| w.url == url) {
+            return Err(PDRouterError::WorkerAlreadyExists { url: url.clone() });
+        }
+
+        workers.push(engine_info);
+
+        // Initialize load tracking
+        self.load_tracking
+            .insert(url.clone(), Arc::new(AtomicUsize::new(0)));
+
+        // Add to cache tree if using cache-aware policy
+        if let Some(ref tree) = self.prefill_tree {
+            tree.lock().unwrap().insert("", &url);
+        }
+
+        info!("Added prefill server: {}", url);
+        Ok(format!("Successfully added prefill server: {}", url))
+    }
+
+    pub async fn add_decode_server(&self, url: String) -> Result<String, PDRouterError> {
+        // Create EngineInfo for the new decode server
+        let engine_info = EngineInfo::new_decode(url.clone());
+
+        // Wait for the new server to be healthy
+        crate::router::Router::wait_for_healthy_workers(
+            &[url.clone()],
+            self.timeout_secs,
+            self.interval_secs,
+        )
+        .map_err(|_| PDRouterError::HealthCheckFailed { url: url.clone() })?;
+
+        // Add to decode workers list
+        let mut workers = self
+            .decode_workers
+            .write()
+            .map_err(|_| PDRouterError::LockError {
+                operation: "decode_workers write".to_string(),
+            })?;
+
+        // Check if already exists
+        if workers.iter().any(|w| w.url == url) {
+            return Err(PDRouterError::WorkerAlreadyExists { url: url.clone() });
+        }
+
+        workers.push(engine_info);
+
+        // Initialize load tracking
+        self.load_tracking
+            .insert(url.clone(), Arc::new(AtomicUsize::new(0)));
+
+        info!("Added decode server: {}", url);
+        Ok(format!("Successfully added decode server: {}", url))
+    }
+
+    pub async fn remove_prefill_server(&self, url: &str) -> Result<String, PDRouterError> {
+        let mut workers = self
+            .prefill_workers
+            .write()
+            .map_err(|_| PDRouterError::LockError {
+                operation: "prefill_workers write".to_string(),
+            })?;
+
+        // Find and remove the server
+        let initial_len = workers.len();
+        workers.retain(|w| w.url != url);
+
+        if workers.len() == initial_len {
+            return Err(PDRouterError::WorkerNotFound {
+                url: url.to_string(),
+            });
+        }
+
+        // Remove from load tracking
+        self.load_tracking.remove(url);
+
+        // Remove from cache tree if using cache-aware policy
+        if let Some(ref tree) = self.prefill_tree {
+            // Note: Tree doesn't have a remove method, so we rebuild it
+            let mut tree_guard = tree.lock().unwrap();
+            *tree_guard = Tree::new();
+            for worker in workers.iter() {
+                tree_guard.insert("", &worker.url);
+            }
+        }
+
+        info!("Removed prefill server: {}", url);
+        Ok(format!("Successfully removed prefill server: {}", url))
+    }
+
+    pub async fn remove_decode_server(&self, url: &str) -> Result<String, PDRouterError> {
+        let mut workers = self
+            .decode_workers
+            .write()
+            .map_err(|_| PDRouterError::LockError {
+                operation: "decode_workers write".to_string(),
+            })?;
+
+        // Find and remove the server
+        let initial_len = workers.len();
+        workers.retain(|w| w.url != url);
+
+        if workers.len() == initial_len {
+            return Err(PDRouterError::WorkerNotFound {
+                url: url.to_string(),
+            });
+        }
+
+        // Remove from load tracking
+        self.load_tracking.remove(url);
+
+        info!("Removed decode server: {}", url);
+        Ok(format!("Successfully removed decode server: {}", url))
+    }
 
     pub fn new(
         prefill_urls: Vec<(String, Option<u16>)>,

sgl-router/src/pd_types.rs

@@ -3,6 +3,31 @@
 use serde::{Deserialize, Serialize};
 use serde_json::Value;
 
+// Custom error type for PD router operations
+#[derive(Debug, thiserror::Error)]
+pub enum PDRouterError {
+    #[error("Worker already exists: {url}")]
+    WorkerAlreadyExists { url: String },
+
+    #[error("Worker not found: {url}")]
+    WorkerNotFound { url: String },
+
+    #[error("Lock acquisition failed: {operation}")]
+    LockError { operation: String },
+
+    #[error("Health check failed for worker: {url}")]
+    HealthCheckFailed { url: String },
+
+    #[error("Invalid worker configuration: {reason}")]
+    InvalidConfiguration { reason: String },
+
+    #[error("Network error: {message}")]
+    NetworkError { message: String },
+
+    #[error("Timeout waiting for worker: {url}")]
+    Timeout { url: String },
+}
+
 #[derive(Debug, Clone)]
 pub enum EngineType {
     Prefill,

sgl-router/src/router.rs

@@ -1045,6 +1045,55 @@ impl Router {
         }
     }
 
+    /// Add a worker with PD mode support
+    pub async fn add_pd_worker(
+        &self,
+        worker_url: &str,
+        pod_type: crate::service_discovery::PodType,
+        bootstrap_port: Option<u16>,
+    ) -> Result<String, String> {
+        match self {
+            Router::PrefillDecode { pd_router } => match pod_type {
+                crate::service_discovery::PodType::Prefill => pd_router
+                    .add_prefill_server(worker_url.to_string(), bootstrap_port)
+                    .await
+                    .map_err(|e| e.to_string()),
+                crate::service_discovery::PodType::Decode => pd_router
+                    .add_decode_server(worker_url.to_string())
+                    .await
+                    .map_err(|e| e.to_string()),
+                crate::service_discovery::PodType::Regular => {
+                    Err("Regular pod type not supported in PD mode".to_string())
+                }
+            },
+            _ => Err("add_pd_worker only supported in PD mode".to_string()),
+        }
+    }
+
+    /// Remove a worker with PD mode support
+    pub async fn remove_pd_worker(
+        &self,
+        worker_url: &str,
+        pod_type: crate::service_discovery::PodType,
+    ) -> Result<String, String> {
+        match self {
+            Router::PrefillDecode { pd_router } => match pod_type {
+                crate::service_discovery::PodType::Prefill => pd_router
+                    .remove_prefill_server(worker_url)
+                    .await
+                    .map_err(|e| e.to_string()),
+                crate::service_discovery::PodType::Decode => pd_router
+                    .remove_decode_server(worker_url)
+                    .await
+                    .map_err(|e| e.to_string()),
+                crate::service_discovery::PodType::Regular => {
+                    Err("Regular pod type not supported in PD mode".to_string())
+                }
+            },
+            _ => Err("remove_pd_worker only supported in PD mode".to_string()),
+        }
+    }
+
     async fn get_worker_load(&self, client: &reqwest::Client, worker_url: &str) -> Option<isize> {
         match client.get(&format!("{}/get_load", worker_url)).send().await {
             Ok(res) if res.status().is_success() => match res.bytes().await {
@@ -1174,3 +1223,108 @@ impl Router {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::service_discovery::PodType;
+
+    fn create_test_regular_router() -> Router {
+        Router::Random {
+            worker_urls: Arc::new(RwLock::new(vec![
+                "http://worker1:8080".to_string(),
+                "http://worker2:8080".to_string(),
+            ])),
+            timeout_secs: 5,
+            interval_secs: 1,
+        }
+    }
+
+    #[test]
+    fn test_router_get_worker_urls_regular() {
+        let router = create_test_regular_router();
+        let worker_urls = router.get_worker_urls();
+        let urls = worker_urls.read().unwrap();
+
+        assert_eq!(urls.len(), 2);
+        assert!(urls.contains(&"http://worker1:8080".to_string()));
+        assert!(urls.contains(&"http://worker2:8080".to_string()));
+    }
+
+    // #[test]
+    // fn test_router_get_worker_urls_pd_mode() {
+    //     // For PD mode, get_worker_urls returns empty list
+    //     // Note: PDRouter::new requires health checks which fail in tests
+    //     // This test would need a mock server or different test setup
+    // }
+
+    #[tokio::test]
+    async fn test_add_pd_worker_with_regular_router() {
+        let router = create_test_regular_router();
+
+        let result = router
+            .add_pd_worker("http://new-worker:8080", PodType::Prefill, Some(8081))
+            .await;
+
+        assert!(result.is_err());
+        assert!(result
+            .unwrap_err()
+            .contains("add_pd_worker only supported in PD mode"));
+    }
+
+    #[tokio::test]
+    async fn test_remove_pd_worker_with_regular_router() {
+        let router = create_test_regular_router();
+
+        let result = router
+            .remove_pd_worker("http://worker:8080", PodType::Decode)
+            .await;
+
+        assert!(result.is_err());
+        assert!(result
+            .unwrap_err()
+            .contains("remove_pd_worker only supported in PD mode"));
+    }
+
+    // #[tokio::test]
+    // async fn test_add_pd_worker_with_pd_router_regular_type() {
+    //     // Note: PDRouter::new requires health checks which fail in tests
+    //     // This test would need a mock server or different test setup
+    // }
+
+    // #[tokio::test]
+    // async fn test_remove_pd_worker_with_pd_router_regular_type() {
+    //     // Note: PDRouter::new requires health checks which fail in tests
+    //     // This test would need a mock server or different test setup
+    // }
+
+    #[test]
+    fn test_select_first_worker_regular() {
+        let router = create_test_regular_router();
+        let result = router.select_first_worker();
+
+        assert!(result.is_ok());
+        assert_eq!(result.unwrap(), "http://worker1:8080");
+    }
+
+    // #[test]
+    // fn test_select_first_worker_pd_mode() {
+    //     // Note: PDRouter::new requires health checks which fail in tests
+    //     // This test would need a mock server or different test setup
+    // }
+
+    #[test]
+    fn test_wait_for_healthy_workers_empty_list() {
+        let result = Router::wait_for_healthy_workers(&[], 1, 1);
+        assert!(result.is_ok());
+    }
+
+    #[test]
+    fn test_wait_for_healthy_workers_invalid_urls() {
+        // This test will timeout quickly since the URLs are invalid
+        let result =
+            Router::wait_for_healthy_workers(&["http://nonexistent:8080".to_string()], 1, 1);
+        assert!(result.is_err());
+        assert!(result.unwrap_err().contains("Timeout"));
+    }
+}

sgl-router/src/service_discovery.rs

@@ -24,6 +24,12 @@ pub struct ServiceDiscoveryConfig {
     pub check_interval: Duration,
     pub port: u16,
     pub namespace: Option<String>,
+    // PD mode specific configuration
+    pub pd_mode: bool,
+    pub prefill_selector: HashMap<String, String>,
+    pub decode_selector: HashMap<String, String>,
+    // Bootstrap port annotation specific to mooncake implementation
+    pub bootstrap_port_annotation: String,
 }
 
 impl Default for ServiceDiscoveryConfig {
@@ -32,12 +38,25 @@ impl Default for ServiceDiscoveryConfig {
             enabled: false,
             selector: HashMap::new(),
             check_interval: Duration::from_secs(60),
-            port: 80,        // Default port to connect to pods
+            port: 8000,      // Standard port for modern services
             namespace: None, // None means watch all namespaces
+            // PD mode defaults
+            pd_mode: false,
+            prefill_selector: HashMap::new(),
+            decode_selector: HashMap::new(),
+            bootstrap_port_annotation: "sglang.ai/bootstrap-port".to_string(),
         }
     }
 }
 
+/// Pod type for PD mode service discovery
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum PodType {
+    Prefill,
+    Decode,
+    Regular,
+}
+
 /// Represents a Kubernetes pod's information used for worker management
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct PodInfo {
@@ -45,10 +64,47 @@ pub struct PodInfo {
     pub ip: String,
     pub status: String,
     pub is_ready: bool,
+    pub pod_type: Option<PodType>,
+    pub bootstrap_port: Option<u16>,
 }
 
 impl PodInfo {
-    pub fn from_pod(pod: &Pod) -> Option<Self> {
+    /// Check if a pod matches any of the given selectors
+    fn matches_selector(pod: &Pod, selector: &HashMap<String, String>) -> bool {
+        if selector.is_empty() {
+            return false;
+        }
+
+        pod.metadata.labels.as_ref().map_or(false, |labels| {
+            selector
+                .iter()
+                .all(|(k, v)| labels.get(k).map_or(false, |label_value| label_value == v))
+        })
+    }
+
+    /// Check if a pod should be included in service discovery
+    pub fn should_include(pod: &Pod, config: &ServiceDiscoveryConfig) -> bool {
+        if config.pd_mode {
+            // In PD mode, at least one selector must be non-empty
+            if config.prefill_selector.is_empty() && config.decode_selector.is_empty() {
+                warn!("PD mode enabled but both prefill_selector and decode_selector are empty");
+                return false;
+            }
+            // In PD mode, pod must match either prefill or decode selector
+            Self::matches_selector(pod, &config.prefill_selector)
+                || Self::matches_selector(pod, &config.decode_selector)
+        } else {
+            // In regular mode, pod must match the general selector
+            if config.selector.is_empty() {
+                warn!("Regular mode enabled but selector is empty");
+                return false;
+            }
+            Self::matches_selector(pod, &config.selector)
+        }
+    }
+
+    /// Unified PodInfo creation with optional PD configuration
+    pub fn from_pod(pod: &Pod, config: Option<&ServiceDiscoveryConfig>) -> Option<Self> {
         let name = pod.metadata.name.clone()?;
         let status = pod.status.clone()?;
         let pod_ip = status.pod_ip?;
@@ -63,11 +119,47 @@ impl PodInfo {
 
         let pod_status = status.phase.unwrap_or_else(|| "Unknown".to_string());
 
+        // Determine pod type based on labels if config is provided and in PD mode
+        let pod_type = if let Some(config) = config {
+            if config.pd_mode {
+                // Use simplified helper methods for cleaner logic
+                if Self::matches_selector(pod, &config.prefill_selector) {
+                    Some(PodType::Prefill)
+                } else if Self::matches_selector(pod, &config.decode_selector) {
+                    Some(PodType::Decode)
+                } else {
+                    Some(PodType::Regular)
+                }
+            } else {
+                Some(PodType::Regular)
+            }
+        } else {
+            // No config provided, default to None (for backwards compatibility)
+            None
+        };
+
+        // Extract bootstrap port from annotations for prefill pods
+        let bootstrap_port = if matches!(pod_type, Some(PodType::Prefill)) {
+            if let Some(config) = config {
+                pod.metadata
+                    .annotations
+                    .as_ref()
+                    .and_then(|annotations| annotations.get(&config.bootstrap_port_annotation))
+                    .and_then(|port_str| port_str.parse::<u16>().ok())
+            } else {
+                None
+            }
+        } else {
+            None
+        };
+
         Some(PodInfo {
             name,
             ip: pod_ip,
             status: pod_status,
             is_ready,
+            pod_type,
+            bootstrap_port,
         })
     }
 
@@ -100,7 +192,27 @@ pub async fn start_service_discovery(
     // Initialize Kubernetes client
     let client = Client::try_default().await?;
 
-    // Construct label selector string from map
+    // Log the appropriate selectors based on mode
+    if config.pd_mode {
+        let prefill_selector = config
+            .prefill_selector
+            .iter()
+            .map(|(k, v)| format!("{}={}", k, v))
+            .collect::<Vec<_>>()
+            .join(",");
+
+        let decode_selector = config
+            .decode_selector
+            .iter()
+            .map(|(k, v)| format!("{}={}", k, v))
+            .collect::<Vec<_>>()
+            .join(",");
+
+        info!(
+            "Starting Kubernetes service discovery in PD mode with prefill_selector: '{}', decode_selector: '{}'",
+            prefill_selector, decode_selector
+        );
+    } else {
         let label_selector = config
             .selector
             .iter()
@@ -109,9 +221,10 @@ pub async fn start_service_discovery(
             .join(",");
 
         info!(
-        "Starting Kubernetes service discovery with selector: {}",
+            "Starting Kubernetes service discovery with selector: '{}'",
             label_selector
         );
+    }
 
     // Create the task that will run in the background
     let handle = task::spawn(async move {
@@ -127,33 +240,30 @@ pub async fn start_service_discovery(
 
         info!("Kubernetes service discovery initialized successfully");
 
-        // Create an Arc for the selector map
+        // Create Arcs for configuration data
-        let selector = Arc::new(config.selector);
+        let config_arc = Arc::new(config.clone());
         let port = config.port;
 
+        let mut retry_delay = Duration::from_secs(1);
+        const MAX_RETRY_DELAY: Duration = Duration::from_secs(300); // 5 minutes max
+
         loop {
             // Create a watcher with the proper parameters according to the kube-rs API
             let watcher_config = Config::default();
             let watcher_stream = watcher(pods.clone(), watcher_config).applied_objects();
 
             // Clone Arcs for the closures
-            let selector_clone = Arc::clone(&selector);
+            let config_clone = Arc::clone(&config_arc);
             let tracked_pods_clone = Arc::clone(&tracked_pods);
 
-            // Apply label selector filter separately since we can't do it directly with the watcher anymore
+            // Simplified label selector filter using helper method
             let filtered_stream = watcher_stream.filter_map(move |obj_res| {
-                let selector_inner = Arc::clone(&selector_clone);
+                let config_inner = Arc::clone(&config_clone);
 
                 async move {
                     match obj_res {
                         Ok(pod) => {
-                            // Only process pods matching our label selector
+                            if PodInfo::should_include(&pod, &config_inner) {
-                            if pod.metadata.labels.as_ref().map_or(false, |labels| {
-                                // Check if the pod has all the labels from our selector
-                                selector_inner.iter().all(|(k, v)| {
-                                    labels.get(k).map_or(false, |label_value| label_value == v)
-                                })
-                            }) {
                                 Some(Ok(pod))
                             } else {
                                 None
@@ -167,24 +277,35 @@ pub async fn start_service_discovery(
             // Clone again for the next closure
             let tracked_pods_clone2 = Arc::clone(&tracked_pods_clone);
             let router_clone = Arc::clone(&router);
+            let config_clone2 = Arc::clone(&config_arc);
 
             match filtered_stream
                 .try_for_each(move |pod| {
                     let tracked_pods_inner = Arc::clone(&tracked_pods_clone2);
                     let router_inner = Arc::clone(&router_clone);
+                    let config_inner = Arc::clone(&config_clone2);
 
                     async move {
-                        if let Some(pod_info) = PodInfo::from_pod(&pod) {
+                        let pod_info = PodInfo::from_pod(&pod, Some(&config_inner));
+
+                        if let Some(pod_info) = pod_info {
                             if pod.metadata.deletion_timestamp.is_some() {
                                 handle_pod_deletion(
                                     &pod_info,
                                     tracked_pods_inner,
                                     router_inner,
                                     port,
+                                    config_inner.pd_mode,
                                 )
                                 .await;
                             } else {
-                                handle_pod_event(&pod_info, tracked_pods_inner, router_inner, port)
+                                handle_pod_event(
+                                    &pod_info,
+                                    tracked_pods_inner,
+                                    router_inner,
+                                    port,
+                                    config_inner.pd_mode,
+                                )
                                 .await;
                             }
                         }
@@ -193,20 +314,29 @@ pub async fn start_service_discovery(
                 })
                 .await
             {
-                Ok(_) => {}
+                Ok(_) => {
+                    // Reset retry delay on success
+                    retry_delay = Duration::from_secs(1);
+                }
                 Err(err) => {
                     error!("Error in Kubernetes watcher: {}", err);
-                    // Wait a bit before retrying
+                    warn!(
-                    time::sleep(Duration::from_secs(5)).await;
+                        "Retrying in {} seconds with exponential backoff",
+                        retry_delay.as_secs()
+                    );
+                    time::sleep(retry_delay).await;
+
+                    // Exponential backoff with jitter
+                    retry_delay = std::cmp::min(retry_delay * 2, MAX_RETRY_DELAY);
                 }
             }
 
             // If the watcher exits for some reason, wait a bit before restarting
             warn!(
                 "Kubernetes watcher exited, restarting in {} seconds",
-                config.check_interval.as_secs()
+                config_arc.check_interval.as_secs()
             );
-            time::sleep(config.check_interval).await;
+            time::sleep(config_arc.check_interval).await;
         }
     });
 
@@ -218,34 +348,64 @@ async fn handle_pod_event(
     tracked_pods: Arc<Mutex<HashSet<PodInfo>>>,
     router: Arc<Router>,
     port: u16,
+    pd_mode: bool,
 ) {
     let worker_url = pod_info.worker_url(port);
 
-    // Check if pod is already tracked
+    // If pod is healthy, try to add it (with atomic check-and-insert)
-    let already_tracked = {
+    if pod_info.is_healthy() {
-        let tracker = tracked_pods.lock().unwrap();
+        // Atomic check-and-insert to prevent race conditions
-        tracker.contains(pod_info)
+        let should_add = {
+            let mut tracker = match tracked_pods.lock() {
+                Ok(tracker) => tracker,
+                Err(e) => {
+                    error!("Failed to acquire tracked_pods lock: {}", e);
+                    return;
+                }
             };
 
-    // If pod is healthy and not already tracked, add it
+            if tracker.contains(pod_info) {
-    if pod_info.is_healthy() {
+                false // Already tracked
-        if !already_tracked {
+            } else {
-            info!(
+                // Reserve the spot to prevent other threads from adding the same pod
-                "Healthy pod found: {}. Adding worker: {}",
-                pod_info.name, worker_url
-            );
-            match router.add_worker(&worker_url).await {
-                Ok(msg) => {
-                    info!("Router add_worker: {}", msg);
-                    let mut tracker = tracked_pods.lock().unwrap();
                 tracker.insert(pod_info.clone());
+                true
+            }
+        };
+
+        if should_add {
+            info!(
+                "Healthy pod found: {} (type: {:?}). Adding worker: {}",
+                pod_info.name, pod_info.pod_type, worker_url
+            );
+
+            let result = if pd_mode && pod_info.pod_type.is_some() {
+                // Use PD-aware worker management
+                if let Some(pod_type) = &pod_info.pod_type {
+                    router
+                        .add_pd_worker(&worker_url, pod_type.clone(), pod_info.bootstrap_port)
+                        .await
+                } else {
+                    Err("Pod type is None in PD mode".to_string())
+                }
+            } else {
+                // Fallback to regular worker management
+                router.add_worker(&worker_url).await
+            };
+
+            match result {
+                Ok(msg) => {
+                    info!("Successfully added worker: {}", msg);
+                }
+                Err(e) => {
+                    error!("Failed to add worker {} to router: {}", worker_url, e);
+                    // Remove from tracking since addition failed
+                    if let Ok(mut tracker) = tracked_pods.lock() {
+                        tracker.remove(pod_info);
+                    }
                 }
-                Err(e) => error!("Failed to add worker {} to router: {}", worker_url, e),
             }
         }
-    } else if already_tracked {
-        // If pod was healthy before but not anymore, remove it
-        handle_pod_deletion(pod_info, tracked_pods, router, port).await;
     }
 }
 
@@ -254,22 +414,47 @@ async fn handle_pod_deletion(
     tracked_pods: Arc<Mutex<HashSet<PodInfo>>>,
     router: Arc<Router>,
     port: u16,
+    pd_mode: bool,
 ) {
     let worker_url = pod_info.worker_url(port);
-    let mut tracked = tracked_pods.lock().unwrap();
 
-    if tracked.remove(pod_info) {
+    let was_tracked = {
+        let mut tracked = match tracked_pods.lock() {
+            Ok(tracked) => tracked,
+            Err(e) => {
+                error!("Failed to acquire tracked_pods lock during deletion: {}", e);
+                return;
+            }
+        };
+        tracked.remove(pod_info)
+    };
+
+    if was_tracked {
         info!(
-            "Pod deleted: {}. Removing worker: {}",
+            "Pod deleted: {} (type: {:?}). Removing worker: {}",
-            pod_info.name, worker_url
+            pod_info.name, pod_info.pod_type, worker_url
         );
+
+        if pd_mode && pod_info.pod_type.is_some() {
+            // Use PD-aware worker removal
+            if let Some(pod_type) = &pod_info.pod_type {
+                if let Err(e) = router.remove_pd_worker(&worker_url, pod_type.clone()).await {
+                    error!(
+                        "Failed to remove PD worker {} from router: {}",
+                        worker_url, e
+                    );
+                }
+            }
+        } else {
+            // Fallback to regular worker removal
             router.remove_worker(&worker_url);
+        }
     } else {
         // This case might occur if a pod is deleted before it was ever marked healthy and added.
         // Or if the event is duplicated. No action needed on the router if it wasn't tracked (and thus not added).
         debug!(
-            "Pod deletion event for untracked/already removed pod: {}. Worker URL: {}",
+            "Pod deletion event for untracked/already removed pod: {} (type: {:?}). Worker URL: {}",
-            pod_info.name, worker_url
+            pod_info.name, pod_info.pod_type, worker_url
         );
     }
 }
@@ -325,6 +510,41 @@ mod tests {
         pod
     }
 
+    // Helper function to create a Pod with PD-specific labels and annotations
+    fn create_pd_k8s_pod(name: &str, ip: &str, pod_type: &str, bootstrap_port: Option<u16>) -> Pod {
+        let mut labels = std::collections::BTreeMap::new();
+        labels.insert("app".to_string(), "sglang".to_string());
+        labels.insert("component".to_string(), pod_type.to_string());
+
+        let mut annotations = std::collections::BTreeMap::new();
+        if let Some(port) = bootstrap_port {
+            annotations.insert("sglang.ai/bootstrap-port".to_string(), port.to_string());
+        }
+
+        Pod {
+            metadata: ObjectMeta {
+                name: Some(name.to_string()),
+                labels: Some(labels),
+                annotations: Some(annotations),
+                ..Default::default()
+            },
+            spec: Some(PodSpec::default()),
+            status: Some(PodStatus {
+                pod_ip: Some(ip.to_string()),
+                phase: Some("Running".to_string()),
+                conditions: Some(vec![PodCondition {
+                    type_: "Ready".to_string(),
+                    status: "True".to_string(),
+                    last_probe_time: None,
+                    last_transition_time: None,
+                    message: None,
+                    reason: None,
+                }]),
+                ..Default::default()
+            }),
+        }
+    }
+
     // Helper to create a Router instance for testing event handlers
     fn create_test_router() -> Arc<Router> {
         let worker_urls = Arc::new(RwLock::new(Vec::new()));
@@ -335,14 +555,80 @@ mod tests {
         })
     }
 
+    // Helper to create a PD config for testing
+    fn create_pd_config() -> ServiceDiscoveryConfig {
+        let mut prefill_selector = HashMap::new();
+        prefill_selector.insert("app".to_string(), "sglang".to_string());
+        prefill_selector.insert("component".to_string(), "prefill".to_string());
+
+        let mut decode_selector = HashMap::new();
+        decode_selector.insert("app".to_string(), "sglang".to_string());
+        decode_selector.insert("component".to_string(), "decode".to_string());
+
+        ServiceDiscoveryConfig {
+            enabled: true,
+            selector: HashMap::new(),
+            check_interval: Duration::from_secs(60),
+            port: 8080,
+            namespace: None,
+            pd_mode: true,
+            prefill_selector,
+            decode_selector,
+            bootstrap_port_annotation: "sglang.ai/bootstrap-port".to_string(),
+        }
+    }
+
+    #[test]
+    fn test_pod_info_should_include() {
+        let config = create_pd_config();
+
+        // Test prefill pod should be included
+        let prefill_pod = create_pd_k8s_pod("prefill-pod", "10.0.0.1", "prefill", Some(8081));
+        assert!(PodInfo::should_include(&prefill_pod, &config));
+
+        // Test decode pod should be included
+        let decode_pod = create_pd_k8s_pod("decode-pod", "10.0.0.2", "decode", None);
+        assert!(PodInfo::should_include(&decode_pod, &config));
+
+        // Test unmatched pod should not be included
+        let unmatched_pod = create_pd_k8s_pod("other-pod", "10.0.0.3", "other", None);
+        assert!(!PodInfo::should_include(&unmatched_pod, &config));
+
+        // Test regular mode
+        let mut regular_config = ServiceDiscoveryConfig::default();
+        regular_config
+            .selector
+            .insert("app".to_string(), "sglang".to_string());
+        regular_config.pd_mode = false;
+
+        let regular_pod = create_pd_k8s_pod("worker-pod", "10.0.0.4", "worker", None);
+        assert!(PodInfo::should_include(&regular_pod, &regular_config));
+    }
+
     #[test]
     fn test_service_discovery_config_default() {
         let config = ServiceDiscoveryConfig::default();
         assert!(!config.enabled);
         assert!(config.selector.is_empty());
         assert_eq!(config.check_interval, Duration::from_secs(60));
-        assert_eq!(config.port, 80);
+        assert_eq!(config.port, 8000);
         assert!(config.namespace.is_none());
+        assert!(!config.pd_mode);
+        assert!(config.prefill_selector.is_empty());
+        assert!(config.decode_selector.is_empty());
+        assert_eq!(config.bootstrap_port_annotation, "sglang.ai/bootstrap-port");
+    }
+
+    #[test]
+    fn test_pod_type_enum() {
+        // Test that PodType enum has expected variants
+        let prefill = PodType::Prefill;
+        let decode = PodType::Decode;
+        let regular = PodType::Regular;
+
+        assert_eq!(format!("{:?}", prefill), "Prefill");
+        assert_eq!(format!("{:?}", decode), "Decode");
+        assert_eq!(format!("{:?}", regular), "Regular");
     }
 
     #[test]
@@ -354,11 +640,85 @@ mod tests {
             Some("True"),
             None,
         );
-        let pod_info = PodInfo::from_pod(&k8s_pod).unwrap();
+        let pod_info = PodInfo::from_pod(&k8s_pod, None).unwrap();
         assert_eq!(pod_info.name, "test-pod");
         assert_eq!(pod_info.ip, "10.0.0.1");
         assert_eq!(pod_info.status, "Running");
         assert!(pod_info.is_ready);
+        assert!(pod_info.pod_type.is_none());
+        assert!(pod_info.bootstrap_port.is_none());
+    }
+
+    #[test]
+    fn test_pod_info_from_pod_with_pd_config_prefill() {
+        let k8s_pod = create_pd_k8s_pod("prefill-pod", "10.0.0.1", "prefill", Some(8081));
+        let config = create_pd_config();
+
+        let pod_info = PodInfo::from_pod(&k8s_pod, Some(&config)).unwrap();
+        assert_eq!(pod_info.name, "prefill-pod");
+        assert_eq!(pod_info.ip, "10.0.0.1");
+        assert_eq!(pod_info.status, "Running");
+        assert!(pod_info.is_ready);
+        assert_eq!(pod_info.pod_type, Some(PodType::Prefill));
+        assert_eq!(pod_info.bootstrap_port, Some(8081));
+    }
+
+    #[test]
+    fn test_pod_info_from_pod_with_pd_config_decode() {
+        let k8s_pod = create_pd_k8s_pod("decode-pod", "10.0.0.2", "decode", None);
+        let config = create_pd_config();
+
+        let pod_info = PodInfo::from_pod(&k8s_pod, Some(&config)).unwrap();
+        assert_eq!(pod_info.name, "decode-pod");
+        assert_eq!(pod_info.ip, "10.0.0.2");
+        assert_eq!(pod_info.status, "Running");
+        assert!(pod_info.is_ready);
+        assert_eq!(pod_info.pod_type, Some(PodType::Decode));
+        assert!(pod_info.bootstrap_port.is_none());
+    }
+
+    #[test]
+    fn test_pod_info_from_pod_with_pd_config_regular_mode() {
+        let k8s_pod = create_pd_k8s_pod("regular-pod", "10.0.0.3", "worker", None);
+        let mut config = create_pd_config();
+        config.pd_mode = false; // Set to regular mode
+
+        let pod_info = PodInfo::from_pod(&k8s_pod, Some(&config)).unwrap();
+        assert_eq!(pod_info.name, "regular-pod");
+        assert_eq!(pod_info.ip, "10.0.0.3");
+        assert_eq!(pod_info.status, "Running");
+        assert!(pod_info.is_ready);
+        assert_eq!(pod_info.pod_type, Some(PodType::Regular));
+        assert!(pod_info.bootstrap_port.is_none());
+    }
+
+    #[test]
+    fn test_pod_info_from_pod_with_pd_config_unmatched_labels() {
+        let k8s_pod = create_pd_k8s_pod("unknown-pod", "10.0.0.4", "unknown", None);
+        let config = create_pd_config();
+
+        let pod_info = PodInfo::from_pod(&k8s_pod, Some(&config)).unwrap();
+        assert_eq!(pod_info.name, "unknown-pod");
+        assert_eq!(pod_info.ip, "10.0.0.4");
+        assert_eq!(pod_info.status, "Running");
+        assert!(pod_info.is_ready);
+        assert_eq!(pod_info.pod_type, Some(PodType::Regular));
+        assert!(pod_info.bootstrap_port.is_none());
+    }
+
+    #[test]
+    fn test_pod_info_from_pod_with_pd_config_invalid_bootstrap_port() {
+        let mut pod = create_pd_k8s_pod("prefill-pod", "10.0.0.1", "prefill", None);
+        // Add invalid bootstrap port annotation
+        pod.metadata.annotations.as_mut().unwrap().insert(
+            "sglang.ai/bootstrap-port".to_string(),
+            "invalid".to_string(),
+        );
+        let config = create_pd_config();
+
+        let pod_info = PodInfo::from_pod(&pod, Some(&config)).unwrap();
+        assert_eq!(pod_info.pod_type, Some(PodType::Prefill));
+        assert!(pod_info.bootstrap_port.is_none()); // Should be None for invalid port
     }
 
     #[test]
@@ -370,7 +730,7 @@ mod tests {
             Some("False"),
             None,
         );
-        let pod_info = PodInfo::from_pod(&k8s_pod).unwrap();
+        let pod_info = PodInfo::from_pod(&k8s_pod, None).unwrap();
         assert!(!pod_info.is_ready);
     }
 
@@ -383,26 +743,26 @@ mod tests {
             None,
             None,
         );
-        let pod_info = PodInfo::from_pod(&k8s_pod).unwrap();
+        let pod_info = PodInfo::from_pod(&k8s_pod, None).unwrap();
         assert!(!pod_info.is_ready);
     }
 
     #[test]
     fn test_pod_info_from_pod_missing_name() {
         let k8s_pod = create_k8s_pod(None, Some("10.0.0.1"), Some("Running"), Some("True"), None);
-        assert!(PodInfo::from_pod(&k8s_pod).is_none());
+        assert!(PodInfo::from_pod(&k8s_pod, None).is_none());
     }
 
     #[test]
     fn test_pod_info_from_pod_missing_ip() {
         let k8s_pod = create_k8s_pod(Some("test-pod"), None, Some("Running"), Some("True"), None);
-        assert!(PodInfo::from_pod(&k8s_pod).is_none());
+        assert!(PodInfo::from_pod(&k8s_pod, None).is_none());
     }
 
     #[test]
     fn test_pod_info_from_pod_missing_status_phase() {
         let k8s_pod = create_k8s_pod(Some("test-pod"), Some("10.0.0.1"), None, Some("True"), None);
-        let pod_info = PodInfo::from_pod(&k8s_pod).unwrap();
+        let pod_info = PodInfo::from_pod(&k8s_pod, None).unwrap();
         assert_eq!(pod_info.status, "Unknown");
     }
 
@@ -410,7 +770,7 @@ mod tests {
     fn test_pod_info_from_pod_no_status_object() {
         let mut k8s_pod = create_k8s_pod(Some("test-pod"), None, None, None, None);
         k8s_pod.status = None;
-        assert!(PodInfo::from_pod(&k8s_pod).is_none());
+        assert!(PodInfo::from_pod(&k8s_pod, None).is_none());
     }
 
     #[test]
@@ -420,6 +780,8 @@ mod tests {
             ip: "1.1.1.1".into(),
             status: "Running".into(),
             is_ready: true,
+            pod_type: None,
+            bootstrap_port: None,
         };
         assert!(healthy_pod.is_healthy());
 
@@ -428,6 +790,8 @@ mod tests {
             ip: "1.1.1.2".into(),
             status: "Running".into(),
             is_ready: false,
+            pod_type: None,
+            bootstrap_port: None,
         };
         assert!(!not_ready_pod.is_healthy());
 
@@ -436,6 +800,8 @@ mod tests {
             ip: "1.1.1.3".into(),
             status: "Pending".into(),
             is_ready: true,
+            pod_type: None,
+            bootstrap_port: None,
         };
         assert!(!not_running_pod.is_healthy());
     }
@@ -447,10 +813,45 @@ mod tests {
             ip: "1.2.3.4".into(),
             status: "Running".into(),
             is_ready: true,
+            pod_type: None,
+            bootstrap_port: None,
         };
         assert_eq!(pod_info.worker_url(8080), "http://1.2.3.4:8080");
     }
 
+    #[test]
+    fn test_pod_info_equality_with_pod_type() {
+        let pod1 = PodInfo {
+            name: "pod1".into(),
+            ip: "1.2.3.4".into(),
+            status: "Running".into(),
+            is_ready: true,
+            pod_type: Some(PodType::Prefill),
+            bootstrap_port: Some(8081),
+        };
+
+        let pod2 = PodInfo {
+            name: "pod1".into(),
+            ip: "1.2.3.4".into(),
+            status: "Running".into(),
+            is_ready: true,
+            pod_type: Some(PodType::Prefill),
+            bootstrap_port: Some(8081),
+        };
+
+        let pod3 = PodInfo {
+            name: "pod1".into(),
+            ip: "1.2.3.4".into(),
+            status: "Running".into(),
+            is_ready: true,
+            pod_type: Some(PodType::Decode),
+            bootstrap_port: None,
+        };
+
+        assert_eq!(pod1, pod2);
+        assert_ne!(pod1, pod3);
+    }
+
     #[tokio::test]
     async fn test_handle_pod_event_add_unhealthy_pod() {
         let router = create_test_router();
@@ -460,6 +861,8 @@ mod tests {
             ip: "1.2.3.4".into(),
             status: "Pending".into(),
             is_ready: false,
+            pod_type: None,
+            bootstrap_port: None,
         };
         let port = 8080u16;
 
@@ -468,6 +871,7 @@ mod tests {
             Arc::clone(&tracked_pods),
             Arc::clone(&router),
             port,
+            false, // pd_mode = false
         )
         .await;
 
@@ -488,6 +892,8 @@ mod tests {
             ip: "1.2.3.4".into(),
             status: "Running".into(),
             is_ready: true,
+            pod_type: None,
+            bootstrap_port: None,
         };
         let port = 8080u16;
 
@@ -496,10 +902,221 @@ mod tests {
             Arc::clone(&tracked_pods),
             Arc::clone(&router),
             port,
+            false, // pd_mode = false
         )
         .await;
 
         assert!(tracked_pods.lock().unwrap().is_empty());
         assert!(router.get_worker_urls().read().unwrap().is_empty());
     }
+
+    #[tokio::test]
+    async fn test_handle_pd_pod_event_prefill_pod() {
+        let router = create_test_router();
+        let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
+        let pod_info = PodInfo {
+            name: "prefill-pod".into(),
+            ip: "1.2.3.4".into(),
+            status: "Running".into(),
+            is_ready: true,
+            pod_type: Some(PodType::Prefill),
+            bootstrap_port: Some(8081),
+        };
+        let port = 8080u16;
+
+        // This test validates the structure but won't actually add workers since
+        // we're using a regular router instead of PD router
+        handle_pod_event(
+            &pod_info,
+            Arc::clone(&tracked_pods),
+            Arc::clone(&router),
+            port,
+            false, // pd_mode = false, so it should fallback to regular handling
+        )
+        .await;
+
+        // Pod should not be tracked since router.add_worker will fail for non-running server
+        assert!(!tracked_pods.lock().unwrap().contains(&pod_info));
+    }
+
+    #[tokio::test]
+    async fn test_handle_pd_pod_event_decode_pod() {
+        let router = create_test_router();
+        let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
+        let pod_info = PodInfo {
+            name: "decode-pod".into(),
+            ip: "1.2.3.5".into(),
+            status: "Running".into(),
+            is_ready: true,
+            pod_type: Some(PodType::Decode),
+            bootstrap_port: None,
+        };
+        let port = 8080u16;
+
+        handle_pod_event(
+            &pod_info,
+            Arc::clone(&tracked_pods),
+            Arc::clone(&router),
+            port,
+            false, // pd_mode = false, so it should fallback to regular handling
+        )
+        .await;
+
+        // Pod should not be tracked since router.add_worker will fail for non-running server
+        assert!(!tracked_pods.lock().unwrap().contains(&pod_info));
+    }
+
+    #[tokio::test]
+    async fn test_handle_pd_pod_deletion_tracked_pod() {
+        let router = create_test_router();
+        let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
+        let pod_info = PodInfo {
+            name: "test-pod".into(),
+            ip: "1.2.3.4".into(),
+            status: "Running".into(),
+            is_ready: true,
+            pod_type: Some(PodType::Prefill),
+            bootstrap_port: Some(8081),
+        };
+
+        // Add pod to tracked set first
+        {
+            let mut tracked = tracked_pods.lock().unwrap();
+            tracked.insert(pod_info.clone());
+        }
+
+        let port = 8080u16;
+
+        handle_pod_deletion(
+            &pod_info,
+            Arc::clone(&tracked_pods),
+            Arc::clone(&router),
+            port,
+            false, // pd_mode = false
+        )
+        .await;
+
+        // Pod should be removed from tracking
+        assert!(!tracked_pods.lock().unwrap().contains(&pod_info));
+    }
+
+    #[tokio::test]
+    async fn test_handle_pd_pod_deletion_untracked_pod() {
+        let router = create_test_router();
+        let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
+        let pod_info = PodInfo {
+            name: "untracked-pod".into(),
+            ip: "1.2.3.4".into(),
+            status: "Running".into(),
+            is_ready: true,
+            pod_type: Some(PodType::Decode),
+            bootstrap_port: None,
+        };
+        let port = 8080u16;
+
+        // Don't add pod to tracked set
+
+        handle_pod_deletion(
+            &pod_info,
+            Arc::clone(&tracked_pods),
+            Arc::clone(&router),
+            port,
+            true, // pd_mode = true
+        )
+        .await;
+
+        // Tracked set should remain empty
+        assert!(tracked_pods.lock().unwrap().is_empty());
+    }
+
+    #[tokio::test]
+    async fn test_unified_handler_regular_mode() {
+        let router = create_test_router();
+        let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
+        let pod_info = PodInfo {
+            name: "regular-pod".into(),
+            ip: "1.2.3.4".into(),
+            status: "Running".into(),
+            is_ready: true,
+            pod_type: Some(PodType::Regular),
+            bootstrap_port: None,
+        };
+        let port = 8080u16;
+
+        // Test that unified handler works for regular mode
+        handle_pod_event(
+            &pod_info,
+            Arc::clone(&tracked_pods),
+            Arc::clone(&router),
+            port,
+            false, // pd_mode = false
+        )
+        .await;
+
+        // Pod should not be tracked since router.add_worker will fail for non-running server
+        assert!(!tracked_pods.lock().unwrap().contains(&pod_info));
+    }
+
+    #[tokio::test]
+    async fn test_unified_handler_pd_mode_with_prefill() {
+        let router = create_test_router();
+        let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
+        let pod_info = PodInfo {
+            name: "prefill-pod".into(),
+            ip: "1.2.3.4".into(),
+            status: "Running".into(),
+            is_ready: true,
+            pod_type: Some(PodType::Prefill),
+            bootstrap_port: Some(8081),
+        };
+        let port = 8080u16;
+
+        // Test that unified handler works for PD mode with prefill
+        handle_pod_event(
+            &pod_info,
+            Arc::clone(&tracked_pods),
+            Arc::clone(&router),
+            port,
+            true, // pd_mode = true
+        )
+        .await;
+
+        // Pod should not be tracked since router.add_pd_worker will fail for regular router
+        assert!(!tracked_pods.lock().unwrap().contains(&pod_info));
+    }
+
+    #[tokio::test]
+    async fn test_unified_handler_deletion_with_pd_mode() {
+        let router = create_test_router();
+        let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
+        let pod_info = PodInfo {
+            name: "decode-pod".into(),
+            ip: "1.2.3.4".into(),
+            status: "Running".into(),
+            is_ready: true,
+            pod_type: Some(PodType::Decode),
+            bootstrap_port: None,
+        };
+
+        // Add pod to tracked set first
+        {
+            let mut tracked = tracked_pods.lock().unwrap();
+            tracked.insert(pod_info.clone());
+        }
+
+        let port = 8080u16;
+
+        // Test that unified handler works for deletion in PD mode
+        handle_pod_deletion(
+            &pod_info,
+            Arc::clone(&tracked_pods),
+            Arc::clone(&router),
+            port,
+            true, // pd_mode = true
+        )
+        .await;
+
+        // Pod should be removed from tracking
+        assert!(!tracked_pods.lock().unwrap().contains(&pod_info));
+    }
 }

sgl-router/tests/test_pd_routing.rs

@@ -5,7 +5,7 @@
 //! - Phase 2: Bootstrap injection and request handling
 //! - Phase 3: Cache-aware selection (when implemented)
 //!
-//! Note: PD mode is enabled via the pd_disaggregated flag, not as a policy type.
+//! Note: PD mode is enabled via the pd_disaggregation flag, not as a policy type.
 //! The policy type (Random, PowerOfTwo, CacheAware) determines the selection algorithm within PD mode.
 
 #[cfg(test)]
@@ -90,7 +90,7 @@ mod test_pd_routing {
     #[test]
     fn test_pd_selection_policies() {
         // Test all PD selection policy variants
-        // Note: These policies are only used when pd_disaggregated=true
+        // Note: These policies are only used when pd_disaggregation=true
         let policies = vec![
             PDSelectionPolicy::Random,
             PDSelectionPolicy::PowerOfTwo,
@@ -122,7 +122,7 @@ mod test_pd_routing {
     #[test]
     fn test_pd_router_configuration() {
         // Test PrefillDecodeConfig creation with various policies
-        // This config is used when pd_disaggregated=true
+        // This config is used when pd_disaggregation=true
         let configs = vec![
             PolicyConfig::PrefillDecodeConfig {
                 selection_policy: PDSelectionPolicy::Random,
@@ -878,7 +878,7 @@ mod test_pd_routing {
     #[test]
     fn test_policy_type_to_pd_selection_policy_mapping() {
         // Document the mapping from PolicyType to PDSelectionPolicy
-        // This mapping happens in lib.rs when pd_disaggregated=true
+        // This mapping happens in lib.rs when pd_disaggregation=true
 
         // PolicyType::Random -> PDSelectionPolicy::Random
         // PolicyType::PowerOfTwo -> PDSelectionPolicy::PowerOfTwo