chore: use u64 as router consumer id instead of uuid (#5478)

Signed-off-by: PeaBrane <yanrpei@gmail.com>

lib/llm/src/discovery/model_manager.rs

@@ -374,9 +374,6 @@ impl ModelManager {
 
         discovery.register(discovery_spec).await?;
 
-        // Use instance_id (hex) as the consumer ID for NATS consumer coordination
-        let consumer_id = instance_id.to_string();
-
         // Get or create runtime config watcher for this endpoint
         let workers_with_configs = self.get_or_create_runtime_config_watcher(endpoint).await?;
 
@@ -388,7 +385,7 @@ impl ModelManager {
             kv_cache_block_size,
             Some(selector),
             kv_router_config,
-            consumer_id,
+            instance_id,
         )
         .await?;
         let new_kv_chooser = Arc::new(chooser);

lib/llm/src/kv_router.rs

@@ -334,7 +334,7 @@ impl KvRouter {
         block_size: u32,
         selector: Option<Box<dyn WorkerSelector + Send + Sync>>,
         kv_router_config: Option<KvRouterConfig>,
-        consumer_id: String,
+        router_id: u64,
     ) -> Result<Self> {
         let kv_router_config = kv_router_config.unwrap_or_default();
         let component = endpoint.component();
@@ -389,7 +389,7 @@ impl KvRouter {
             workers_with_configs.clone(),
             selector,
             kv_router_config.router_replica_sync,
-            consumer_id.clone(),
+            router_id,
         )
         .await?;
 
@@ -442,6 +442,8 @@ impl KvRouter {
                     "Not all workers have local_indexer enabled, using JetStream subscription"
                 );
 
+                // Convert router_id to string for NATS consumer naming
+                let consumer_id = router_id.to_string();
                 start_kv_router_background(
                     component.clone(),
                     consumer_id,

lib/llm/src/kv_router/protocols.rs

@@ -3,7 +3,6 @@
 
 use crate::tokens::{SequenceHash, Token};
 use serde::{Deserialize, Serialize};
-use uuid::Uuid;
 use xxhash_rust::xxh3;
 
 /// Seed for XXH3 hashing, consistent with indexer.rs
@@ -265,7 +264,7 @@ pub struct PrefillEvent {
     pub request_id: String,
     pub worker_id: WorkerId,
     pub data: PrefillEventData,
-    pub router_id: Uuid,
+    pub router_id: u64,
 }
 
 /// Represents the different stages of prefilling tokens for a request.
@@ -284,7 +283,7 @@ pub struct ActiveSequenceEvent {
     pub request_id: String,
     pub worker: WorkerWithDpRank,
     pub data: ActiveSequenceEventData,
-    pub router_id: Uuid,
+    pub router_id: u64,
 }
 
 #[derive(Serialize, Deserialize, Debug, Clone)]

lib/llm/src/kv_router/scheduler.rs

@@ -99,7 +99,7 @@ impl KvScheduler {
         workers_with_configs: Arc<RuntimeConfigsWithNotify>,
         selector: Option<Box<dyn WorkerSelector + Send + Sync>>,
         replica_sync: bool,
-        router_uuid: String,
+        router_id: u64,
     ) -> Result<Self, KvSchedulerError> {
         let selector = selector.unwrap_or(Box::new(DefaultWorkerSelector::default()));
 
@@ -116,7 +116,7 @@ impl KvScheduler {
             block_size as usize,
             initial_workers,
             replica_sync,
-            router_uuid,
+            router_id,
         ));
 
         // Spawn background task to sync slots with DashMap when notified of changes.

lib/llm/src/kv_router/sequence.rs

@@ -409,7 +409,7 @@ pub struct ActiveSequencesMultiWorker {
     handles: Arc<DashMap<WorkerWithDpRank, std::thread::JoinHandle<()>>>,
     block_size: usize,
     component: Component,
-    router_id: Uuid,
+    router_id: u64,
     replica_sync: bool,
 }
 
@@ -419,21 +419,13 @@ impl ActiveSequencesMultiWorker {
         block_size: usize,
         workers_with_configs: HashMap<u64, Option<ModelRuntimeConfig>>,
         replica_sync: bool,
-        router_uuid: String,
+        router_id: u64,
     ) -> Self {
         assert!(block_size > 1, "block_size must be greater than 1");
 
         let senders = Arc::new(DashMap::new());
         let handles = Arc::new(DashMap::new());
         let request_to_worker = Arc::new(DashMap::new());
-        let router_id = Uuid::parse_str(&router_uuid).unwrap_or_else(|e| {
-            tracing::warn!(
-                "Failed to parse router UUID '{}': {}, using new UUID",
-                router_uuid,
-                e
-            );
-            Uuid::new_v4()
-        });
 
         // Expand workers by their dp_rank
         for (worker_id, config) in workers_with_configs {
@@ -602,7 +594,7 @@ impl ActiveSequencesMultiWorker {
         >,
         request_to_worker: Arc<DashMap<RequestId, WorkerWithDpRank>>,
         component: Component,
-        router_id: Uuid,
+        router_id: u64,
         cancel_token: CancellationToken,
     ) -> Result<()> {
         let mut subscriber = component
@@ -1249,14 +1241,14 @@ mod tests {
             block_size,
             workers_with_configs.clone(),
             true,
-            Uuid::new_v4().to_string(),
+            1,
         ));
         let seq_manager_2 = Arc::new(ActiveSequencesMultiWorker::new(
             component,
             block_size,
             workers_with_configs,
             true,
-            Uuid::new_v4().to_string(),
+            2,
         ));
 
         // Give some time for the subscription loops to start
@@ -1408,14 +1400,14 @@ mod tests {
             block_size,
             workers_with_configs.clone(),
             true,
-            Uuid::new_v4().to_string(),
+            1,
         ));
         let seq_manager_2 = Arc::new(ActiveSequencesMultiWorker::new(
             component,
             block_size,
             workers_with_configs,
             true,
-            Uuid::new_v4().to_string(),
+            2,
         ));
 
         // Give some time for the subscription loops to start

lib/llm/src/kv_router/subscriber.rs

@@ -654,7 +654,7 @@ pub async fn start_kv_router_background(
 
                     let router_instance_id = id.instance_id();
 
-                    // The consumer UUID is the instance_id in hex format
+                    // The consumer ID is the instance_id as a string
                     let consumer_to_delete = router_instance_id.to_string();
 
                     tracing::info!(