sglang_v0.5.2/sglang/sgl-router/py_src/sglang_router/router.py

130 lines
7.6 KiB
Python

from typing import Optional
from sglang_router.router_args import RouterArgs
from sglang_router_rs import PolicyType
from sglang_router_rs import Router as _Router
def policy_from_str(policy_str: Optional[str]) -> PolicyType:
"""Convert policy string to PolicyType enum."""
if policy_str is None:
return None
policy_map = {
"random": PolicyType.Random,
"round_robin": PolicyType.RoundRobin,
"cache_aware": PolicyType.CacheAware,
"power_of_two": PolicyType.PowerOfTwo,
}
return policy_map[policy_str]
class Router:
"""
A high-performance router for distributing requests across worker nodes.
Args:
worker_urls: List of URLs for worker nodes that will handle requests. Each URL should include
the protocol, host, and port (e.g., ['http://worker1:8000', 'http://worker2:8000'])
policy: Load balancing policy to use. Options:
- PolicyType.Random: Randomly select workers
- PolicyType.RoundRobin: Distribute requests in round-robin fashion
- PolicyType.CacheAware: Distribute requests based on cache state and load balance
- PolicyType.PowerOfTwo: Select best of two random workers based on load (PD mode only)
host: Host address to bind the router server. Default: '127.0.0.1'
port: Port number to bind the router server. Default: 3001
worker_startup_timeout_secs: Timeout in seconds for worker startup. Default: 300
worker_startup_check_interval: Interval in seconds between checks for worker initialization. Default: 10
cache_threshold: Cache threshold (0.0-1.0) for cache-aware routing. Routes to cached worker
if the match rate exceeds threshold, otherwise routes to the worker with the smallest
tree. Default: 0.5
balance_abs_threshold: Load balancing is triggered when (max_load - min_load) > abs_threshold
AND max_load > min_load * rel_threshold. Otherwise, use cache aware. Default: 32
balance_rel_threshold: Load balancing is triggered when (max_load - min_load) > abs_threshold
AND max_load > min_load * rel_threshold. Otherwise, use cache aware. Default: 1.0001
eviction_interval_secs: Interval in seconds between cache eviction operations in cache-aware
routing. Default: 60
max_payload_size: Maximum payload size in bytes. Default: 256MB
max_tree_size: Maximum size of the approximation tree for cache-aware routing. Default: 2^24
dp_aware: Enable data parallelism aware schedule. Default: False
api_key: The api key used for the authorization with the worker.
Useful when the dp aware scheduling strategy is enabled.
Default: None
log_dir: Directory to store log files. If None, logs are only output to console. Default: None
log_level: Logging level. Options: 'debug', 'info', 'warning', 'error', 'critical'.
service_discovery: Enable Kubernetes service discovery. When enabled, the router will
automatically discover worker pods based on the selector. Default: False
selector: Dictionary mapping of label keys to values for Kubernetes pod selection.
Example: {"app": "sglang-worker"}. Default: {}
service_discovery_port: Port to use for service discovery. The router will generate
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_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)
prefill_policy: Specific load balancing policy for prefill nodes (PD mode only).
If not specified, uses the main policy. Default: None
decode_policy: Specific load balancing policy for decode nodes (PD mode only).
If not specified, uses the main policy. Default: None
request_id_headers: List of HTTP headers to check for request IDs. If not specified,
uses common defaults: ['x-request-id', 'x-correlation-id', 'x-trace-id', 'request-id'].
Example: ['x-my-request-id', 'x-custom-trace-id']. Default: None
bootstrap_port_annotation: Kubernetes annotation name for bootstrap port (PD mode).
Default: 'sglang.ai/bootstrap-port'
request_timeout_secs: Request timeout in seconds. Default: 600
max_concurrent_requests: Maximum number of concurrent requests allowed for rate limiting. Default: 256
queue_size: Queue size for pending requests when max concurrent limit reached (0 = no queue, return 429 immediately). Default: 100
queue_timeout_secs: Maximum time (in seconds) a request can wait in queue before timing out. Default: 60
rate_limit_tokens_per_second: Token bucket refill rate (tokens per second). If not set, defaults to max_concurrent_requests. Default: None
cors_allowed_origins: List of allowed origins for CORS. Empty list allows all origins. Default: []
health_failure_threshold: Number of consecutive health check failures before marking worker unhealthy. Default: 3
health_success_threshold: Number of consecutive health check successes before marking worker healthy. Default: 2
health_check_timeout_secs: Timeout in seconds for health check requests. Default: 5
health_check_interval_secs: Interval in seconds between runtime health checks. Default: 60
health_check_endpoint: Health check endpoint path. Default: '/health'
model_path: Model path for loading tokenizer (HuggingFace model ID or local path). Default: None
tokenizer_path: Explicit tokenizer path (overrides model_path tokenizer if provided). Default: None
"""
def __init__(self, router: _Router):
self._router = router
@staticmethod
def from_args(args: RouterArgs) -> "Router":
"""Create a router from a RouterArgs instance."""
args_dict = vars(args)
# Convert RouterArgs to _Router parameters
args_dict["worker_urls"] = (
[]
if args_dict["service_discovery"] or args_dict["pd_disaggregation"]
else args_dict["worker_urls"]
)
args_dict["policy"] = policy_from_str(args_dict["policy"])
args_dict["prefill_urls"] = (
args_dict["prefill_urls"] if args_dict["pd_disaggregation"] else None
)
args_dict["decode_urls"] = (
args_dict["decode_urls"] if args_dict["pd_disaggregation"] else None
)
args_dict["prefill_policy"] = policy_from_str(args_dict["prefill_policy"])
args_dict["decode_policy"] = policy_from_str(args_dict["decode_policy"])
# remoge mini_lb parameter
args_dict.pop("mini_lb")
return Router(_Router(**args_dict))
def start(self) -> None:
"""Start the router server.
This method blocks until the server is shut down.
"""
self._router.start()