[router] Add Rust Binary Entrypoint for SGLang Router (#9089)

sgl-router/Cargo.toml

@@ -9,7 +9,12 @@ name = "sglang_router_rs"
 # Python/C binding + Rust library: Use ["cdylib", "rlib"]
 crate-type = ["cdylib", "rlib"]
 
+[[bin]]
+name = "sglang-router"
+path = "src/main.rs"
+
 [dependencies]
+clap = { version = "4", features = ["derive"] }
 axum = { version = "0.8.4", features = ["macros", "ws", "tracing"] }
 tower = { version = "0.5", features = ["full"] }
 tower-http = { version = "0.6", features = ["trace", "compression-gzip", "cors", "timeout", "limit", "request-id", "util"] }

sgl-router/README.md

@@ -56,7 +56,21 @@ pip install -e .
 cargo build
 ```
 
-#### Launch Router with Worker URLs in regular mode
+#### Using the Rust Binary Directly (Alternative to Python)
+```bash
+# Build the Rust binary
+cargo build --release
+
+# Launch router with worker URLs in regular mode
+./target/release/sglang-router \
+    --worker-urls http://worker1:8000 http://worker2:8000
+
+# Or use cargo run
+cargo run --release -- \
+    --worker-urls http://worker1:8000 http://worker2:8000
+```
+
+#### Launch Router with Python (Original Method)
 ```bash
 # Launch router with worker URLs
 python -m sglang_router.launch_router \
@@ -68,7 +82,22 @@ python -m sglang_router.launch_router \
 # Note that the prefill and decode URLs must be provided in the following format:
 # http://<ip>:<port> for  decode nodes
 # http://<ip>:<port> bootstrap-port for  prefill nodes, where bootstrap-port is optional
-# Launch router with worker URLs
+
+# Using Rust binary directly
+./target/release/sglang-router \
+    --pd-disaggregation \
+    --policy cache_aware \
+    --prefill http://127.0.0.1:30001 9001 \
+    --prefill http://127.0.0.2:30002 9002 \
+    --prefill http://127.0.0.3:30003 9003 \
+    --prefill http://127.0.0.4:30004 9004 \
+    --decode http://127.0.0.5:30005 \
+    --decode http://127.0.0.6:30006 \
+    --decode http://127.0.0.7:30007 \
+    --host 0.0.0.0 \
+    --port 8080
+
+# Or using Python launcher
 python -m sglang_router.launch_router \
     --pd-disaggregation \
     --policy cache_aware \

sgl-router/src/main.rs

@@ -0,0 +1,490 @@
+use clap::{ArgAction, Parser};
+use sglang_router_rs::config::{
+    CircuitBreakerConfig, ConfigError, ConfigResult, DiscoveryConfig, MetricsConfig, PolicyConfig,
+    RetryConfig, RouterConfig, RoutingMode,
+};
+use sglang_router_rs::metrics::PrometheusConfig;
+use sglang_router_rs::server::{self, ServerConfig};
+use sglang_router_rs::service_discovery::ServiceDiscoveryConfig;
+use std::collections::HashMap;
+
+// Helper function to parse prefill arguments from command line
+fn parse_prefill_args() -> Vec<(String, Option<u16>)> {
+    let args: Vec<String> = std::env::args().collect();
+    let mut prefill_entries = Vec::new();
+    let mut i = 0;
+
+    while i < args.len() {
+        if args[i] == "--prefill" && i + 1 < args.len() {
+            let url = args[i + 1].clone();
+            let bootstrap_port = if i + 2 < args.len() && !args[i + 2].starts_with("--") {
+                // Check if next arg is a port number
+                if let Ok(port) = args[i + 2].parse::<u16>() {
+                    i += 1; // Skip the port argument
+                    Some(port)
+                } else if args[i + 2].to_lowercase() == "none" {
+                    i += 1; // Skip the "none" argument
+                    None
+                } else {
+                    None
+                }
+            } else {
+                None
+            };
+            prefill_entries.push((url, bootstrap_port));
+            i += 2; // Skip --prefill and URL
+        } else {
+            i += 1;
+        }
+    }
+
+    prefill_entries
+}
+
+#[derive(Parser, Debug)]
+#[command(name = "sglang-router")]
+#[command(about = "SGLang Router - High-performance request distribution across worker nodes")]
+#[command(long_about = r#"
+SGLang Router - High-performance request distribution across worker nodes
+
+Usage:
+This launcher enables starting a router with individual worker instances. It is useful for
+multi-node setups or when you want to start workers and router separately.
+
+Examples:
+  # Regular mode
+  sglang-router --worker-urls http://worker1:8000 http://worker2:8000
+
+  # PD disaggregated mode with same policy for both
+  sglang-router --pd-disaggregation \
+    --prefill http://127.0.0.1:30001 9001 \
+    --prefill http://127.0.0.2:30002 9002 \
+    --decode http://127.0.0.3:30003 \
+    --decode http://127.0.0.4:30004 \
+    --policy cache_aware
+
+  # PD mode with different policies for prefill and decode
+  sglang-router --pd-disaggregation \
+    --prefill http://127.0.0.1:30001 9001 \
+    --prefill http://127.0.0.2:30002 \
+    --decode http://127.0.0.3:30003 \
+    --decode http://127.0.0.4:30004 \
+    --prefill-policy cache_aware --decode-policy power_of_two
+"#)]
+struct CliArgs {
+    /// Host address to bind the router server
+    #[arg(long, default_value = "127.0.0.1")]
+    host: String,
+
+    /// Port number to bind the router server
+    #[arg(long, default_value_t = 30000)]
+    port: u16,
+
+    /// List of worker URLs (e.g., http://worker1:8000 http://worker2:8000)
+    #[arg(long, num_args = 0..)]
+    worker_urls: Vec<String>,
+
+    /// Load balancing policy to use
+    #[arg(long, default_value = "cache_aware", value_parser = ["random", "round_robin", "cache_aware", "power_of_two"])]
+    policy: String,
+
+    /// Enable PD (Prefill-Decode) disaggregated mode
+    #[arg(long, default_value_t = false)]
+    pd_disaggregation: bool,
+
+    /// Decode server URL (can be specified multiple times)
+    #[arg(long, action = ArgAction::Append)]
+    decode: Vec<String>,
+
+    /// Specific policy for prefill nodes in PD mode
+    #[arg(long, value_parser = ["random", "round_robin", "cache_aware", "power_of_two"])]
+    prefill_policy: Option<String>,
+
+    /// Specific policy for decode nodes in PD mode
+    #[arg(long, value_parser = ["random", "round_robin", "cache_aware", "power_of_two"])]
+    decode_policy: Option<String>,
+
+    /// Timeout in seconds for worker startup
+    #[arg(long, default_value_t = 300)]
+    worker_startup_timeout_secs: u64,
+
+    /// Interval in seconds between checks for worker startup
+    #[arg(long, default_value_t = 10)]
+    worker_startup_check_interval: u64,
+
+    /// Cache threshold (0.0-1.0) for cache-aware routing
+    #[arg(long, default_value_t = 0.5)]
+    cache_threshold: f32,
+
+    /// Absolute threshold for load balancing
+    #[arg(long, default_value_t = 32)]
+    balance_abs_threshold: usize,
+
+    /// Relative threshold for load balancing
+    #[arg(long, default_value_t = 1.0001)]
+    balance_rel_threshold: f32,
+
+    /// Interval in seconds between cache eviction operations
+    #[arg(long, default_value_t = 60)]
+    eviction_interval: u64,
+
+    /// Maximum size of the approximation tree for cache-aware routing
+    #[arg(long, default_value_t = 16777216)] // 2^24
+    max_tree_size: usize,
+
+    /// Maximum payload size in bytes
+    #[arg(long, default_value_t = 268435456)] // 256MB
+    max_payload_size: usize,
+
+    /// Enable data parallelism aware schedule
+    #[arg(long, default_value_t = false)]
+    dp_aware: bool,
+
+    /// API key for worker authorization
+    #[arg(long)]
+    api_key: Option<String>,
+
+    /// Directory to store log files
+    #[arg(long)]
+    log_dir: Option<String>,
+
+    /// Set the logging level
+    #[arg(long, default_value = "info", value_parser = ["debug", "info", "warn", "error"])]
+    log_level: String,
+
+    /// Enable Kubernetes service discovery
+    #[arg(long, default_value_t = false)]
+    service_discovery: bool,
+
+    /// Label selector for Kubernetes service discovery (format: key1=value1 key2=value2)
+    #[arg(long, num_args = 0..)]
+    selector: Vec<String>,
+
+    /// Port to use for discovered worker pods
+    #[arg(long, default_value_t = 80)]
+    service_discovery_port: u16,
+
+    /// Kubernetes namespace to watch for pods
+    #[arg(long)]
+    service_discovery_namespace: Option<String>,
+
+    /// Label selector for prefill server pods in PD mode
+    #[arg(long, num_args = 0..)]
+    prefill_selector: Vec<String>,
+
+    /// Label selector for decode server pods in PD mode
+    #[arg(long, num_args = 0..)]
+    decode_selector: Vec<String>,
+
+    /// Port to expose Prometheus metrics
+    #[arg(long, default_value_t = 29000)]
+    prometheus_port: u16,
+
+    /// Host address to bind the Prometheus metrics server
+    #[arg(long, default_value = "127.0.0.1")]
+    prometheus_host: String,
+
+    /// Custom HTTP headers to check for request IDs
+    #[arg(long, num_args = 0..)]
+    request_id_headers: Vec<String>,
+
+    /// Request timeout in seconds
+    #[arg(long, default_value_t = 600)]
+    request_timeout_secs: u64,
+
+    /// Maximum number of concurrent requests allowed
+    #[arg(long, default_value_t = 64)]
+    max_concurrent_requests: usize,
+
+    /// CORS allowed origins
+    #[arg(long, num_args = 0..)]
+    cors_allowed_origins: Vec<String>,
+
+    // Retry configuration
+    /// Maximum number of retries
+    #[arg(long, default_value_t = 3)]
+    retry_max_retries: u32,
+
+    /// Initial backoff in milliseconds for retries
+    #[arg(long, default_value_t = 100)]
+    retry_initial_backoff_ms: u64,
+
+    /// Maximum backoff in milliseconds for retries
+    #[arg(long, default_value_t = 10000)]
+    retry_max_backoff_ms: u64,
+
+    /// Backoff multiplier for exponential backoff
+    #[arg(long, default_value_t = 2.0)]
+    retry_backoff_multiplier: f32,
+
+    /// Jitter factor for retry backoff
+    #[arg(long, default_value_t = 0.1)]
+    retry_jitter_factor: f32,
+
+    /// Disable retries
+    #[arg(long, default_value_t = false)]
+    disable_retries: bool,
+
+    // Circuit breaker configuration
+    /// Number of failures before circuit breaker opens
+    #[arg(long, default_value_t = 5)]
+    cb_failure_threshold: u32,
+
+    /// Number of successes before circuit breaker closes
+    #[arg(long, default_value_t = 2)]
+    cb_success_threshold: u32,
+
+    /// Timeout duration in seconds for circuit breaker
+    #[arg(long, default_value_t = 30)]
+    cb_timeout_duration_secs: u64,
+
+    /// Window duration in seconds for circuit breaker
+    #[arg(long, default_value_t = 60)]
+    cb_window_duration_secs: u64,
+
+    /// Disable circuit breaker
+    #[arg(long, default_value_t = false)]
+    disable_circuit_breaker: bool,
+}
+
+impl CliArgs {
+    /// Parse selector strings into HashMap
+    fn parse_selector(selector_list: &[String]) -> HashMap<String, String> {
+        let mut map = HashMap::new();
+        for item in selector_list {
+            if let Some(eq_pos) = item.find('=') {
+                let key = item[..eq_pos].to_string();
+                let value = item[eq_pos + 1..].to_string();
+                map.insert(key, value);
+            }
+        }
+        map
+    }
+
+    /// Convert policy string to PolicyConfig
+    fn parse_policy(&self, policy_str: &str) -> PolicyConfig {
+        match policy_str {
+            "random" => PolicyConfig::Random,
+            "round_robin" => PolicyConfig::RoundRobin,
+            "cache_aware" => PolicyConfig::CacheAware {
+                cache_threshold: self.cache_threshold,
+                balance_abs_threshold: self.balance_abs_threshold,
+                balance_rel_threshold: self.balance_rel_threshold,
+                eviction_interval_secs: self.eviction_interval,
+                max_tree_size: self.max_tree_size,
+            },
+            "power_of_two" => PolicyConfig::PowerOfTwo {
+                load_check_interval_secs: 5, // Default value
+            },
+            _ => PolicyConfig::RoundRobin, // Fallback
+        }
+    }
+
+    /// Convert CLI arguments to RouterConfig
+    fn to_router_config(
+        &self,
+        prefill_urls: Vec<(String, Option<u16>)>,
+    ) -> ConfigResult<RouterConfig> {
+        // Determine routing mode
+        let mode = if self.pd_disaggregation {
+            let decode_urls = self.decode.clone();
+
+            // Validate PD configuration if not using service discovery
+            if !self.service_discovery && (prefill_urls.is_empty() || decode_urls.is_empty()) {
+                return Err(ConfigError::ValidationFailed {
+                    reason: "PD disaggregation mode requires --prefill and --decode URLs when not using service discovery".to_string(),
+                });
+            }
+
+            RoutingMode::PrefillDecode {
+                prefill_urls,
+                decode_urls,
+                prefill_policy: self.prefill_policy.as_ref().map(|p| self.parse_policy(p)),
+                decode_policy: self.decode_policy.as_ref().map(|p| self.parse_policy(p)),
+            }
+        } else {
+            // Regular mode
+            if !self.service_discovery && self.worker_urls.is_empty() {
+                return Err(ConfigError::ValidationFailed {
+                    reason: "Regular mode requires --worker-urls when not using service discovery"
+                        .to_string(),
+                });
+            }
+            RoutingMode::Regular {
+                worker_urls: self.worker_urls.clone(),
+            }
+        };
+
+        // Main policy
+        let policy = self.parse_policy(&self.policy);
+
+        // Service discovery configuration
+        let discovery = if self.service_discovery {
+            Some(DiscoveryConfig {
+                enabled: true,
+                namespace: self.service_discovery_namespace.clone(),
+                port: self.service_discovery_port,
+                check_interval_secs: 60,
+                selector: Self::parse_selector(&self.selector),
+                prefill_selector: Self::parse_selector(&self.prefill_selector),
+                decode_selector: Self::parse_selector(&self.decode_selector),
+                bootstrap_port_annotation: "sglang.ai/bootstrap-port".to_string(),
+            })
+        } else {
+            None
+        };
+
+        // Metrics configuration
+        let metrics = Some(MetricsConfig {
+            port: self.prometheus_port,
+            host: self.prometheus_host.clone(),
+        });
+
+        // Build RouterConfig
+        Ok(RouterConfig {
+            mode,
+            policy,
+            host: self.host.clone(),
+            port: self.port,
+            max_payload_size: self.max_payload_size,
+            request_timeout_secs: self.request_timeout_secs,
+            worker_startup_timeout_secs: self.worker_startup_timeout_secs,
+            worker_startup_check_interval_secs: self.worker_startup_check_interval,
+            dp_aware: self.dp_aware,
+            api_key: self.api_key.clone(),
+            discovery,
+            metrics,
+            log_dir: self.log_dir.clone(),
+            log_level: Some(self.log_level.clone()),
+            request_id_headers: if self.request_id_headers.is_empty() {
+                None
+            } else {
+                Some(self.request_id_headers.clone())
+            },
+            max_concurrent_requests: self.max_concurrent_requests,
+            cors_allowed_origins: self.cors_allowed_origins.clone(),
+            retry: RetryConfig {
+                max_retries: self.retry_max_retries,
+                initial_backoff_ms: self.retry_initial_backoff_ms,
+                max_backoff_ms: self.retry_max_backoff_ms,
+                backoff_multiplier: self.retry_backoff_multiplier,
+                jitter_factor: self.retry_jitter_factor,
+            },
+            circuit_breaker: CircuitBreakerConfig {
+                failure_threshold: self.cb_failure_threshold,
+                success_threshold: self.cb_success_threshold,
+                timeout_duration_secs: self.cb_timeout_duration_secs,
+                window_duration_secs: self.cb_window_duration_secs,
+            },
+            disable_retries: self.disable_retries,
+            disable_circuit_breaker: self.disable_circuit_breaker,
+        })
+    }
+
+    /// Create ServerConfig from CLI args and RouterConfig
+    fn to_server_config(&self, router_config: RouterConfig) -> ServerConfig {
+        // Create service discovery config if enabled
+        let service_discovery_config = if self.service_discovery {
+            Some(ServiceDiscoveryConfig {
+                enabled: true,
+                selector: Self::parse_selector(&self.selector),
+                check_interval: std::time::Duration::from_secs(60),
+                port: self.service_discovery_port,
+                namespace: self.service_discovery_namespace.clone(),
+                pd_mode: self.pd_disaggregation,
+                prefill_selector: Self::parse_selector(&self.prefill_selector),
+                decode_selector: Self::parse_selector(&self.decode_selector),
+                bootstrap_port_annotation: "sglang.ai/bootstrap-port".to_string(),
+            })
+        } else {
+            None
+        };
+
+        // Create Prometheus config
+        let prometheus_config = Some(PrometheusConfig {
+            port: self.prometheus_port,
+            host: self.prometheus_host.clone(),
+        });
+
+        ServerConfig {
+            host: self.host.clone(),
+            port: self.port,
+            router_config,
+            max_payload_size: self.max_payload_size,
+            log_dir: self.log_dir.clone(),
+            log_level: Some(self.log_level.clone()),
+            service_discovery_config,
+            prometheus_config,
+            request_timeout_secs: self.request_timeout_secs,
+            request_id_headers: if self.request_id_headers.is_empty() {
+                None
+            } else {
+                Some(self.request_id_headers.clone())
+            },
+        }
+    }
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    // Parse prefill arguments manually before clap parsing
+    let prefill_urls = parse_prefill_args();
+
+    // Filter out prefill arguments and their values before passing to clap
+    let mut filtered_args: Vec<String> = Vec::new();
+    let raw_args: Vec<String> = std::env::args().collect();
+    let mut i = 0;
+
+    while i < raw_args.len() {
+        if raw_args[i] == "--prefill" && i + 1 < raw_args.len() {
+            // Skip --prefill and its URL
+            i += 2;
+            // Also skip bootstrap port if present
+            if i < raw_args.len() && !raw_args[i].starts_with("--") {
+                if raw_args[i].parse::<u16>().is_ok() || raw_args[i].to_lowercase() == "none" {
+                    i += 1;
+                }
+            }
+        } else {
+            filtered_args.push(raw_args[i].clone());
+            i += 1;
+        }
+    }
+
+    // Parse CLI arguments with clap using filtered args
+    let cli_args = CliArgs::parse_from(filtered_args);
+
+    // Print startup info
+    println!("SGLang Router starting...");
+    println!("Host: {}:{}", cli_args.host, cli_args.port);
+    println!(
+        "Mode: {}",
+        if cli_args.pd_disaggregation {
+            "PD Disaggregated"
+        } else {
+            "Regular"
+        }
+    );
+    println!("Policy: {}", cli_args.policy);
+
+    if cli_args.pd_disaggregation && !prefill_urls.is_empty() {
+        println!("Prefill nodes: {:?}", prefill_urls);
+        println!("Decode nodes: {:?}", cli_args.decode);
+    }
+
+    // Convert to RouterConfig
+    let router_config = cli_args.to_router_config(prefill_urls)?;
+
+    // Validate configuration
+    router_config.validate()?;
+
+    // Create ServerConfig
+    let server_config = cli_args.to_server_config(router_config);
+
+    // Create a new runtime for the server (like Python binding does)
+    let runtime = tokio::runtime::Runtime::new()?;
+
+    // Block on the async startup function
+    runtime.block_on(async move { server::startup(server_config).await })?;
+
+    Ok(())
+}

sgl-router/src/routers/factory.rs

@@ -11,29 +11,32 @@ pub struct RouterFactory;
 
 impl RouterFactory {
     /// Create a router instance from application context
-    pub fn create_router(ctx: &Arc<AppContext>) -> Result<Box<dyn RouterTrait>, String> {
+    pub async fn create_router(ctx: &Arc<AppContext>) -> Result<Box<dyn RouterTrait>, String> {
         match &ctx.router_config.mode {
             RoutingMode::Regular { worker_urls } => {
-                Self::create_regular_router(worker_urls, &ctx.router_config.policy, ctx)
+                Self::create_regular_router(worker_urls, &ctx.router_config.policy, ctx).await
             }
             RoutingMode::PrefillDecode {
                 prefill_urls,
                 decode_urls,
                 prefill_policy,
                 decode_policy,
-            } => Self::create_pd_router(
-                prefill_urls,
-                decode_urls,
-                prefill_policy.as_ref(),
-                decode_policy.as_ref(),
-                &ctx.router_config.policy,
-                ctx,
-            ),
+            } => {
+                Self::create_pd_router(
+                    prefill_urls,
+                    decode_urls,
+                    prefill_policy.as_ref(),
+                    decode_policy.as_ref(),
+                    &ctx.router_config.policy,
+                    ctx,
+                )
+                .await
+            }
         }
     }
 
     /// Create a regular router with injected policy
-    fn create_regular_router(
+    async fn create_regular_router(
         worker_urls: &[String],
         policy_config: &PolicyConfig,
         ctx: &Arc<AppContext>,
@@ -52,13 +55,14 @@ impl RouterFactory {
             ctx.router_config.api_key.clone(),
             ctx.router_config.retry.clone(),
             ctx.router_config.circuit_breaker.clone(),
-        )?;
+        )
+        .await?;
 
         Ok(Box::new(router))
     }
 
     /// Create a PD router with injected policy
-    fn create_pd_router(
+    async fn create_pd_router(
         prefill_urls: &[(String, Option<u16>)],
         decode_urls: &[String],
         prefill_policy_config: Option<&PolicyConfig>,
@@ -83,7 +87,8 @@ impl RouterFactory {
             ctx.router_config.worker_startup_check_interval_secs,
             ctx.router_config.retry.clone(),
             ctx.router_config.circuit_breaker.clone(),
-        )?;
+        )
+        .await?;
 
         Ok(Box::new(router))
     }

sgl-router/src/routers/pd_router.rs

@@ -67,6 +67,7 @@ impl PDRouter {
             self.timeout_secs,
             self.interval_secs,
         )
+        .await
         .map_err(|_| PDRouterError::HealthCheckFailed {
             url: url.to_string(),
         })
@@ -349,7 +350,7 @@ impl PDRouter {
         Ok(format!("Successfully removed decode server: {}", url))
     }
 
-    pub fn new(
+    pub async fn new(
         prefill_urls: Vec<(String, Option<u16>)>,
         decode_urls: Vec<String>,
         prefill_policy: Arc<dyn LoadBalancingPolicy>,
@@ -392,7 +393,8 @@ impl PDRouter {
                 &all_urls,
                 timeout_secs,
                 interval_secs,
-            )?;
+            )
+            .await?;
         }
 
         // Initialize cache-aware policies with workers

sgl-router/src/routers/router.rs

@@ -17,7 +17,6 @@ use futures_util::StreamExt;
 use reqwest::Client;
 use std::collections::HashMap;
 use std::sync::{Arc, RwLock};
-use std::thread;
 use std::time::{Duration, Instant};
 use tokio_stream::wrappers::UnboundedReceiverStream;
 use tracing::{debug, error, info, warn};
@@ -52,7 +51,7 @@ pub struct Router {
 
 impl Router {
     /// Create a new router with injected policy and client
-    pub fn new(
+    pub async fn new(
         worker_urls: Vec<String>,
         policy: Arc<dyn LoadBalancingPolicy>,
         client: Client,
@@ -68,7 +67,7 @@ impl Router {
 
         // Wait for workers to be healthy (skip if empty - for service discovery mode)
         if !worker_urls.is_empty() {
-            Self::wait_for_healthy_workers(&worker_urls, timeout_secs, interval_secs)?;
+            Self::wait_for_healthy_workers(&worker_urls, timeout_secs, interval_secs).await?;
         }
 
         let worker_urls = if dp_aware {
@@ -156,7 +155,7 @@ impl Router {
             .collect()
     }
 
-    pub fn wait_for_healthy_workers(
+    pub async fn wait_for_healthy_workers(
         worker_urls: &[String],
         timeout_secs: u64,
         interval_secs: u64,
@@ -167,9 +166,24 @@ impl Router {
             );
         }
 
+        // Perform health check asynchronously
+        Self::wait_for_healthy_workers_async(worker_urls, timeout_secs, interval_secs).await
+    }
+
+    async fn wait_for_healthy_workers_async(
+        worker_urls: &[String],
+        timeout_secs: u64,
+        interval_secs: u64,
+    ) -> Result<(), String> {
+        info!(
+            "Waiting for {} workers to become healthy (timeout: {}s)",
+            worker_urls.len(),
+            timeout_secs
+        );
+
         let start_time = std::time::Instant::now();
-        let sync_client = reqwest::blocking::Client::builder()
-            .timeout(Duration::from_secs(timeout_secs))
+        let client = reqwest::Client::builder()
+            .timeout(Duration::from_secs(2))
             .build()
             .map_err(|e| format!("Failed to create HTTP client: {}", e))?;
 
@@ -185,20 +199,48 @@ impl Router {
                 ));
             }
 
+            // Perform all health checks concurrently
+            let mut health_checks = Vec::new();
+            for url in worker_urls {
+                let client_clone = client.clone();
+                let url_clone = url.clone();
+
+                let check_health = tokio::spawn(async move {
+                    let health_url = format!("{}/health", url_clone);
+                    match client_clone.get(&health_url).send().await {
+                        Ok(res) => {
+                            if res.status().is_success() {
+                                None
+                            } else {
+                                Some((url_clone, format!("status: {}", res.status())))
+                            }
+                        }
+                        Err(_) => Some((url_clone, "not ready".to_string())),
+                    }
+                });
+
+                health_checks.push(check_health);
+            }
+
+            // Wait for all health checks to complete
+            let results = futures::future::join_all(health_checks).await;
+
             let mut all_healthy = true;
             let mut unhealthy_workers = Vec::new();
 
-            for url in worker_urls {
-                match sync_client.get(&format!("{}/health", url)).send() {
-                    Ok(res) => {
-                        if !res.status().is_success() {
-                            all_healthy = false;
-                            unhealthy_workers.push((url, format!("status: {}", res.status())));
-                        }
+            for result in results {
+                match result {
+                    Ok(None) => {
+                        // Worker is healthy
                     }
-                    Err(_) => {
+                    Ok(Some((url, reason))) => {
                         all_healthy = false;
-                        unhealthy_workers.push((url, "not ready".to_string()));
+                        unhealthy_workers.push((url, reason));
+                    }
+                    Err(e) => {
+                        all_healthy = false;
+                        unhealthy_workers
+                            .push(("unknown".to_string(), format!("task error: {}", e)));
                     }
                 }
             }
@@ -208,11 +250,12 @@ impl Router {
                 return Ok(());
             } else {
                 debug!(
-                    "Waiting for {} workers to become healthy ({} unhealthy)",
+                    "Waiting for {} workers to become healthy ({} unhealthy: {:?})",
                     worker_urls.len(),
-                    unhealthy_workers.len()
+                    unhealthy_workers.len(),
+                    unhealthy_workers
                 );
-                thread::sleep(Duration::from_secs(interval_secs));
+                tokio::time::sleep(Duration::from_secs(interval_secs)).await;
             }
         }
     }
@@ -1246,19 +1289,19 @@ mod tests {
         assert_eq!(result.unwrap(), "http://worker1:8080");
     }
 
-    #[test]
-    fn test_wait_for_healthy_workers_empty_list() {
-        // Empty list will timeout as there are no workers to check
-        let result = Router::wait_for_healthy_workers(&[], 1, 1);
+    #[tokio::test]
+    async fn test_wait_for_healthy_workers_empty_list() {
+        // Empty list will return error immediately
+        let result = Router::wait_for_healthy_workers(&[], 1, 1).await;
         assert!(result.is_err());
-        assert!(result.unwrap_err().contains("Timeout"));
+        assert!(result.unwrap_err().contains("no workers provided"));
     }
 
-    #[test]
-    fn test_wait_for_healthy_workers_invalid_urls() {
+    #[tokio::test]
+    async 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);
+            Router::wait_for_healthy_workers(&["http://nonexistent:8080".to_string()], 1, 1).await;
         assert!(result.is_err());
         assert!(result.unwrap_err().contains("Timeout"));
     }

sgl-router/src/server.rs

@@ -285,7 +285,7 @@ pub async fn startup(config: ServerConfig) -> Result<(), Box<dyn std::error::Err
     ));
 
     // Create router with the context
-    let router = RouterFactory::create_router(&app_context)?;
+    let router = RouterFactory::create_router(&app_context).await?;
 
     // Create app state with router and context
     let app_state = Arc::new(AppState {

sgl-router/src/service_discovery.rs

@@ -576,7 +576,7 @@ mod tests {
     }
 
     // Helper to create a Router instance for testing event handlers
-    fn create_test_router() -> Arc<dyn RouterTrait> {
+    async fn create_test_router() -> Arc<dyn RouterTrait> {
         use crate::config::PolicyConfig;
         use crate::policies::PolicyFactory;
         use crate::routers::router::Router;
@@ -593,6 +593,7 @@ mod tests {
             crate::config::types::RetryConfig::default(),
             crate::config::types::CircuitBreakerConfig::default(),
         )
+        .await
         .unwrap();
         Arc::new(router) as Arc<dyn RouterTrait>
     }
@@ -896,7 +897,7 @@ mod tests {
 
     #[tokio::test]
     async fn test_handle_pod_event_add_unhealthy_pod() {
-        let router = create_test_router();
+        let router = create_test_router().await;
         let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
         let pod_info = PodInfo {
             name: "pod1".into(),
@@ -925,7 +926,7 @@ mod tests {
 
     #[tokio::test]
     async fn test_handle_pod_deletion_non_existing_pod() {
-        let router = create_test_router();
+        let router = create_test_router().await;
         let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
         let pod_info = PodInfo {
             name: "pod1".into(),
@@ -952,7 +953,7 @@ mod tests {
 
     #[tokio::test]
     async fn test_handle_pd_pod_event_prefill_pod() {
-        let router = create_test_router();
+        let router = create_test_router().await;
         let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
         let pod_info = PodInfo {
             name: "prefill-pod".into(),
@@ -981,7 +982,7 @@ mod tests {
 
     #[tokio::test]
     async fn test_handle_pd_pod_event_decode_pod() {
-        let router = create_test_router();
+        let router = create_test_router().await;
         let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
         let pod_info = PodInfo {
             name: "decode-pod".into(),
@@ -1008,7 +1009,7 @@ mod tests {
 
     #[tokio::test]
     async fn test_handle_pd_pod_deletion_tracked_pod() {
-        let router = create_test_router();
+        let router = create_test_router().await;
         let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
         let pod_info = PodInfo {
             name: "test-pod".into(),
@@ -1042,7 +1043,7 @@ mod tests {
 
     #[tokio::test]
     async fn test_handle_pd_pod_deletion_untracked_pod() {
-        let router = create_test_router();
+        let router = create_test_router().await;
         let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
         let pod_info = PodInfo {
             name: "untracked-pod".into(),
@@ -1071,7 +1072,7 @@ mod tests {
 
     #[tokio::test]
     async fn test_unified_handler_regular_mode() {
-        let router = create_test_router();
+        let router = create_test_router().await;
         let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
         let pod_info = PodInfo {
             name: "regular-pod".into(),
@@ -1099,7 +1100,7 @@ mod tests {
 
     #[tokio::test]
     async fn test_unified_handler_pd_mode_with_prefill() {
-        let router = create_test_router();
+        let router = create_test_router().await;
         let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
         let pod_info = PodInfo {
             name: "prefill-pod".into(),
@@ -1127,7 +1128,7 @@ mod tests {
 
     #[tokio::test]
     async fn test_unified_handler_deletion_with_pd_mode() {
-        let router = create_test_router();
+        let router = create_test_router().await;
         let tracked_pods = Arc::new(Mutex::new(HashSet::new()));
         let pod_info = PodInfo {
             name: "decode-pod".into(),

sgl-router/tests/api_endpoints_test.rs

@@ -92,12 +92,8 @@ impl TestContext {
         // Create app context
         let app_context = common::create_test_context(config.clone());
 
-        // Create router using sync factory in a blocking context
-        let router =
-            tokio::task::spawn_blocking(move || RouterFactory::create_router(&app_context))
-                .await
-                .unwrap()
-                .unwrap();
+        // Create router
+        let router = RouterFactory::create_router(&app_context).await.unwrap();
         let router = Arc::from(router);
 
         // Wait for router to discover workers
@@ -1451,10 +1447,7 @@ mod pd_mode_tests {
         let app_context = common::create_test_context(config);
 
         // Create router - this might fail due to health check issues
-        let router_result =
-            tokio::task::spawn_blocking(move || RouterFactory::create_router(&app_context))
-                .await
-                .unwrap();
+        let router_result = RouterFactory::create_router(&app_context).await;
 
         // Clean up workers
         prefill_worker.stop().await;

sgl-router/tests/request_formats_test.rs

@@ -60,11 +60,7 @@ impl TestContext {
         config.mode = RoutingMode::Regular { worker_urls };
 
         let app_context = common::create_test_context(config);
-        let router =
-            tokio::task::spawn_blocking(move || RouterFactory::create_router(&app_context))
-                .await
-                .unwrap()
-                .unwrap();
+        let router = RouterFactory::create_router(&app_context).await.unwrap();
         let router = Arc::from(router);
 
         if !workers.is_empty() {

sgl-router/tests/streaming_tests.rs

@@ -61,11 +61,7 @@ impl TestContext {
         config.mode = RoutingMode::Regular { worker_urls };
 
         let app_context = common::create_test_context(config);
-        let router =
-            tokio::task::spawn_blocking(move || RouterFactory::create_router(&app_context))
-                .await
-                .unwrap()
-                .unwrap();
+        let router = RouterFactory::create_router(&app_context).await.unwrap();
         let router = Arc::from(router);
 
         if !workers.is_empty() {

sgl-router/tests/test_pd_routing.rs

@@ -109,8 +109,8 @@ mod test_pd_routing {
         }
     }
 
-    #[test]
-    fn test_pd_router_configuration() {
+    #[tokio::test]
+    async fn test_pd_router_configuration() {
         // Test PD router configuration with various policies
         // In the new structure, RoutingMode and PolicyConfig are separate
         let test_cases = vec![
@@ -190,7 +190,7 @@ mod test_pd_routing {
             let app_context =
                 sglang_router_rs::server::AppContext::new(config, reqwest::Client::new(), 64);
             let app_context = std::sync::Arc::new(app_context);
-            let result = RouterFactory::create_router(&app_context);
+            let result = RouterFactory::create_router(&app_context).await;
             assert!(result.is_err());
             let error_msg = result.unwrap_err();
             // Error should be about health/timeout, not configuration