[sgl-router] refactor - layout BucketResolver, Bucket, EngineGroup and implement PowerOfTwo (#40241)
Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>
This commit is contained in:
Kan Wu
co-authored by
Claude Fable 5.1
Claude Fable 5.1
parent
4a9dc5c4af
commit
aedda8377e
@@ -10,5 +10,8 @@
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mod discovery;
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mod health;
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mod policies;
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mod policies_reorg;
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mod policies_reorg_load;
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mod policies_reorg_power_of_two;
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mod tokenizer;
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mod workers;
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@@ -0,0 +1,486 @@
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// SPDX-FileCopyrightText: Copyright (c) 2026 The SGLang Authors
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// SPDX-License-Identifier: Apache-2.0
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use std::sync::{Arc, Mutex};
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use futures::future::BoxFuture;
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use sgl_router::buckets_reorg::{
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Bucket, BucketGroups, BucketRequest, BucketResolver, EngineGroup, TokenLimits,
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};
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use sgl_router::discovery::{ModelId, WorkerId, WorkerSpec};
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use sgl_router::policies_reorg::admission::{AllowAll, Decision, EngineAdmission};
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use sgl_router::policies_reorg::{Pick, PickError, PickRequest, Policy, Rejection, Stage};
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use sgl_router::state::load_monitor::engine_reported_load::EngineReportedWorkerLoad;
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use sgl_router::workers::{Worker, WorkerRegistry};
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#[derive(Debug)]
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struct TestPolicy {
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admission: Arc<dyn EngineAdmission>,
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result: Option<Arc<Worker>>,
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miss: bool,
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invalid: bool,
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calls: Mutex<Vec<String>>,
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}
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impl Default for TestPolicy {
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fn default() -> Self {
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Self {
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admission: Arc::new(AllowAll),
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result: None,
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miss: false,
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invalid: false,
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calls: Mutex::new(Vec::new()),
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}
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}
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}
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impl Policy for TestPolicy {
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fn pick<'a>(
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&'a self,
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engines: &'a [Arc<Worker>],
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request: &'a PickRequest<'a>,
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) -> BoxFuture<'a, Result<Pick, PickError>> {
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Box::pin(async move {
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self.calls.lock().unwrap().push(request.bucket.to_owned());
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if self.invalid {
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return Err(PickError::InvalidSignal("test signal".into()));
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}
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if self.miss {
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return Err(PickError::NoCandidates);
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}
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if engines.is_empty() {
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return Err(PickError::NoCandidates);
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}
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let engine = self.result.clone().unwrap_or_else(|| engines[0].clone());
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if let Decision::Reject(reason) = self.admission.check(&engine, request, None)? {
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return Err(PickError::AdmissionRejected(Rejection {
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engine: engine.id.clone(),
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reason,
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}));
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}
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Ok(Pick {
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engine,
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reason: "test",
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})
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})
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}
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}
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#[derive(Debug)]
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struct Reject(&'static str);
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impl EngineAdmission for Reject {
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fn check(
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&self,
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engine: &Worker,
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_: &PickRequest<'_>,
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_: Option<&EngineReportedWorkerLoad>,
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) -> Result<Decision, PickError> {
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Ok(if engine.id.0 == self.0 {
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Decision::Reject("full".into())
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} else {
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Decision::Allow
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})
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}
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}
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fn spec(id: &str, mode: Stage, model: &str) -> WorkerSpec {
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WorkerSpec {
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id: WorkerId(id.into()),
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url: format!("http://{id}"),
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mode,
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model_ids: vec![ModelId(model.into())],
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bootstrap_port: None,
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}
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}
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fn registry() -> Arc<WorkerRegistry> {
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let workers = Arc::new(WorkerRegistry::default());
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for (id, mode, model) in [
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("a", Stage::Plain, "m"),
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("b", Stage::Plain, "m"),
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("unhealthy", Stage::Plain, "m"),
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("other", Stage::Plain, "other"),
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("p", Stage::Prefill, "pd"),
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("d", Stage::Decode, "pd"),
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] {
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workers.add(spec(id, mode, model)).unwrap();
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}
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let unhealthy = workers.get(&WorkerId("unhealthy".into())).unwrap();
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for _ in 0..3 {
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unhealthy.breaker.record_failure();
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}
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workers
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}
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fn group(members: &[&str], policy: Arc<dyn Policy>) -> EngineGroup {
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EngineGroup {
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worker_ids: Some(members.iter().map(|id| WorkerId((*id).into())).collect()),
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policy,
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}
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}
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fn bucket(id: &str, max: Option<u64>, policy: Arc<dyn Policy>) -> Bucket {
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let mut bucket = Bucket::new(id, BucketGroups::Plain(EngineGroup::new(policy)));
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bucket.limits.max = max;
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bucket
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}
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#[tokio::test]
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async fn groups_isolate_model_health_stage_and_membership() {
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let workers = registry();
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let model = ModelId("m".into());
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let request = PickRequest::new(&model, Stage::Plain, 10);
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let group = EngineGroup::new(Arc::new(TestPolicy::default()));
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assert_eq!(
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group.pick(&workers, &request).await.unwrap().engine.id.0,
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"a"
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);
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workers.remove(&WorkerId("a".into()));
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assert_eq!(
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group.pick(&workers, &request).await.unwrap().engine.id.0,
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"b"
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);
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workers.remove(&WorkerId("b".into()));
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assert!(matches!(
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group.pick(&workers, &request).await,
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Err(PickError::NoCandidates)
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));
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let pd = ModelId("pd".into());
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for (stage, expected) in [(Stage::Prefill, "p"), (Stage::Decode, "d")] {
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let request = PickRequest::new(&pd, stage, 10);
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let group = self::group(
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&["p", "d", "other", "unhealthy"],
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Arc::new(TestPolicy::default()),
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);
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assert_eq!(
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group.pick(&workers, &request).await.unwrap().engine.id.0,
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expected
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);
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}
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let empty = self::group(&[], Arc::new(TestPolicy::default()));
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assert!(matches!(
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empty.pick(&workers, &request).await,
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Err(PickError::NoCandidates)
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));
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}
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#[test]
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fn resolve_orders_all_length_fits_by_capacity_rank_and_id() {
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let policy = Arc::new(TestPolicy::default());
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let mut z = bucket("z", Some(20), policy.clone());
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z.rank = 1;
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let mut a = bucket("a", Some(20), policy.clone());
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a.rank = 1;
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let mut later = bucket("later", Some(20), policy.clone());
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later.rank = 2;
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let mut min = bucket("min", Some(15), policy.clone());
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min.limits.min = Some(11);
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let resolver = BucketResolver::new(vec![
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bucket("catch-all", None, policy.clone()),
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bucket("too-small", Some(9), policy),
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z,
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later,
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a,
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min,
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]);
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assert_eq!(
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resolver
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.resolve(10, None)
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.unwrap()
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.iter()
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.map(|bucket| bucket.id.as_str())
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.collect::<Vec<_>>(),
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["a", "z", "later", "catch-all"]
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);
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assert_eq!(resolver.resolve(11, None).unwrap()[0].id, "min");
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assert_eq!(resolver.resolve(15, None).unwrap()[0].id, "min");
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assert_eq!(resolver.resolve(20, None).unwrap()[0].id, "a");
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assert_eq!(resolver.resolve(21, None).unwrap()[0].id, "catch-all");
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}
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#[test]
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fn context_capacity_checks_peak_when_known_and_input_otherwise() {
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let policy = Arc::new(TestPolicy::default());
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let mut short = bucket("short", None, policy.clone());
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short.max_context_tokens = Some(20);
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let mut long = bucket("long", None, policy);
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long.max_context_tokens = Some(30);
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let resolver = BucketResolver::new(vec![long, short]);
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assert_eq!(resolver.resolve(10, None).unwrap()[0].id, "short");
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assert_eq!(resolver.resolve(10, Some(20)).unwrap()[0].id, "short");
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assert_eq!(resolver.resolve(10, Some(21)).unwrap()[0].id, "long");
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assert!(resolver.resolve(10, Some(31)).unwrap().is_empty());
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assert!(resolver.resolve(31, None).unwrap().is_empty());
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assert!(matches!(
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resolver.resolve(10, Some(9)),
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Err(PickError::InvalidSignal(_))
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));
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assert!(BucketResolver::default()
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.resolve(1, None)
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.unwrap()
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.is_empty());
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}
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#[tokio::test]
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async fn selected_pd_bucket_owns_both_memberships_and_policies() {
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let workers = registry();
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workers.add(spec("p2", Stage::Prefill, "pd")).unwrap();
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workers.add(spec("d2", Stage::Decode, "pd")).unwrap();
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let model = ModelId("pd".into());
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let prefill_policy = Arc::new(TestPolicy::default());
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let decode_policy = Arc::new(TestPolicy::default());
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let resolver = BucketResolver::new(vec![Bucket::new(
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"shared",
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BucketGroups::Pd {
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prefill: group(&["p2", "d", "a"], prefill_policy.clone()),
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decode: group(&["d2", "p", "other"], decode_policy.clone()),
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},
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)]);
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let bucket = resolver.resolve(10, Some(20)).unwrap()[0];
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let request = BucketRequest {
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model: &model,
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input_tokens: 10,
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expected_peak_tokens: Some(20),
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token_ids: None,
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session_key: None,
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routing_key: None,
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};
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let picks = bucket.pick_engines(&workers, &request).await.unwrap();
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assert_eq!(picks.prefill.engine.id.0, "p2");
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assert_eq!(picks.decode.unwrap().engine.id.0, "d2");
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assert_eq!(*prefill_policy.calls.lock().unwrap(), ["shared"]);
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assert_eq!(*decode_policy.calls.lock().unwrap(), ["shared"]);
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}
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#[tokio::test]
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async fn resolver_includes_empty_groups_without_invoking_policies() {
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let workers = registry();
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let model = ModelId("m".into());
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let policy = Arc::new(TestPolicy::default());
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let mut empty = Bucket::new(
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"empty",
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BucketGroups::Plain(group(&["missing"], policy.clone())),
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);
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empty.limits = TokenLimits {
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min: None,
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max: Some(10),
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};
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let resolver = BucketResolver::new(vec![empty, bucket("available", Some(20), policy.clone())]);
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let buckets = resolver.resolve(10, None).unwrap();
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assert_eq!(
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buckets
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.iter()
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.map(|bucket| bucket.id.as_str())
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.collect::<Vec<_>>(),
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["empty", "available"]
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);
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let bucket = buckets[0];
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let BucketGroups::Plain(group) = &bucket.groups else {
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panic!("expected plain")
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};
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let request = PickRequest {
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bucket: &bucket.id,
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..PickRequest::new(&model, Stage::Plain, 10)
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};
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assert!(matches!(
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group.pick(&workers, &request).await,
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Err(PickError::NoCandidates)
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));
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assert!(policy.calls.lock().unwrap().is_empty());
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}
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#[tokio::test]
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async fn group_propagates_rejections_misses_and_invalid_signals() {
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let workers = registry();
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let model = ModelId("m".into());
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let request = PickRequest::new(&model, Stage::Plain, 10);
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let rejected = group(
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&["a"],
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Arc::new(TestPolicy {
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admission: Arc::new(Reject("a")),
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..Default::default()
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}),
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);
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assert!(matches!(
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rejected.pick(&workers, &request).await,
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Err(PickError::AdmissionRejected(_))
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));
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let miss = group(
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&["a"],
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Arc::new(TestPolicy {
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miss: true,
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..Default::default()
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}),
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);
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assert!(matches!(
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miss.pick(&workers, &request).await,
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Err(PickError::NoCandidates)
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));
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let invalid = group(
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&["a"],
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Arc::new(TestPolicy {
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invalid: true,
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..Default::default()
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}),
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);
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assert!(matches!(
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invalid.pick(&workers, &request).await,
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Err(PickError::InvalidSignal(_))
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));
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}
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#[tokio::test]
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async fn group_rejects_foreign_pick_even_with_same_worker_id() {
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let workers = registry();
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let model = ModelId("m".into());
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let request = PickRequest::new(&model, Stage::Plain, 10);
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let group = group(
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&["a"],
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Arc::new(TestPolicy {
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result: Some(Arc::new(Worker::new(spec("a", Stage::Plain, "m")))),
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..Default::default()
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}),
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);
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assert!(matches!(
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group.pick(&workers, &request).await,
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Err(PickError::OutsideCandidates(_))
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));
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}
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#[tokio::test]
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async fn selected_engine_rejection_does_not_try_an_alternative() {
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let model = ModelId("m".into());
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let request = PickRequest::new(&model, Stage::Plain, 10);
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let engines = [
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Arc::new(Worker::new(spec("a", Stage::Plain, "m"))),
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Arc::new(Worker::new(spec("b", Stage::Plain, "m"))),
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];
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let policy = TestPolicy {
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admission: Arc::new(Reject("a")),
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..Default::default()
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};
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assert!(matches!(
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policy.pick(&engines, &request).await,
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Err(PickError::AdmissionRejected(_))
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));
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assert!(matches!(
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policy.pick(&[], &request).await,
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Err(PickError::NoCandidates)
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));
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}
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#[tokio::test]
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async fn bucket_scopes_plain_pick_and_preserves_request_facts() {
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#[derive(Debug)]
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struct InspectRequest;
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impl Policy for InspectRequest {
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fn pick<'a>(
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&'a self,
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engines: &'a [Arc<Worker>],
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request: &'a PickRequest<'a>,
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) -> BoxFuture<'a, Result<Pick, PickError>> {
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Box::pin(async move {
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assert_eq!(request.model.0, "m");
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assert_eq!(request.bucket, "plain-bucket");
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assert_eq!(request.stage, Stage::Plain);
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assert_eq!(request.input_tokens, 2);
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assert_eq!(request.expected_peak_tokens, Some(12));
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assert_eq!(request.token_ids, Some([7, 9].as_slice()));
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assert_eq!(request.session_key, Some("session"));
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assert_eq!(request.routing_key, Some("routing"));
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Ok(Pick {
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engine: engines[0].clone(),
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reason: "inspected",
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})
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})
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}
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}
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let workers = registry();
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let model = ModelId("m".into());
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let bucket = Bucket::new(
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"plain-bucket",
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BucketGroups::Plain(group(&["b"], Arc::new(InspectRequest))),
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);
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let request = BucketRequest {
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model: &model,
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input_tokens: 2,
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expected_peak_tokens: Some(12),
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token_ids: Some(&[7, 9]),
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session_key: Some("session"),
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routing_key: Some("routing"),
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};
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let picks = bucket.pick_engines(&workers, &request).await.unwrap();
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assert_eq!(picks.prefill.engine.id.0, "b");
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assert_eq!(picks.prefill.reason, "inspected");
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assert!(picks.decode.is_none());
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}
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#[tokio::test]
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async fn power_of_two_checks_selected_engine_and_propagates_rejection_without_fallback() {
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use sgl_router::policies_reorg::power_of_two::PowerOfTwoPolicy;
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use sgl_router::state::load_monitor::engine_reported_load::EngineReportedLoadTable;
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#[derive(Debug)]
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struct Check {
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calls: Mutex<Vec<WorkerId>>,
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reject: bool,
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invalid: bool,
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}
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impl EngineAdmission for Check {
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fn check(
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&self,
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engine: &Worker,
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_: &PickRequest<'_>,
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_: Option<&EngineReportedWorkerLoad>,
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) -> Result<Decision, PickError> {
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self.calls.lock().unwrap().push(engine.id.clone());
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if self.invalid {
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Err(PickError::InvalidSignal("admission input".into()))
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} else if self.reject {
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Ok(Decision::Reject("full".into()))
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} else {
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Ok(Decision::Allow)
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}
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}
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}
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let model = ModelId("m".into());
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let request = PickRequest::new(&model, Stage::Plain, 10);
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let engine = Arc::new(Worker::new(spec("a", Stage::Plain, "m")));
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let other = Arc::new(Worker::new(spec("b", Stage::Plain, "m")));
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let _busy = other.load_guard();
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for engines in [vec![engine.clone()], vec![other.clone(), engine.clone()]] {
|
||||
for (reject, invalid) in [(false, false), (true, false), (false, true)] {
|
||||
let check = Arc::new(Check {
|
||||
calls: Mutex::new(Vec::new()),
|
||||
reject,
|
||||
invalid,
|
||||
});
|
||||
let mut policy = PowerOfTwoPolicy::new(EngineReportedLoadTable::new());
|
||||
policy.admission = check.clone();
|
||||
assert!(matches!(
|
||||
policy.pick(&[], &request).await,
|
||||
Err(PickError::NoCandidates)
|
||||
));
|
||||
assert!(check.calls.lock().unwrap().is_empty());
|
||||
let result = policy.pick(&engines, &request).await;
|
||||
if invalid {
|
||||
assert!(matches!(result, Err(PickError::InvalidSignal(_))));
|
||||
} else if reject {
|
||||
assert!(matches!(result, Err(PickError::AdmissionRejected(reason))
|
||||
if reason.engine == engine.id && reason.reason == "full"));
|
||||
} else {
|
||||
assert!(Arc::ptr_eq(&result.unwrap().engine, &engine));
|
||||
}
|
||||
assert_eq!(
|
||||
check.calls.lock().unwrap().as_slice(),
|
||||
std::slice::from_ref(&engine.id)
|
||||
);
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,138 @@
|
||||
// SPDX-FileCopyrightText: Copyright (c) 2026 The SGLang Authors
|
||||
// SPDX-License-Identifier: Apache-2.0
|
||||
|
||||
use std::sync::{Arc, Mutex};
|
||||
use std::time::{Duration, Instant};
|
||||
|
||||
use sgl_router::discovery::{ModelId, WorkerId, WorkerSpec};
|
||||
use sgl_router::policies_reorg::admission::{Decision, EngineAdmission};
|
||||
use sgl_router::policies_reorg::power_of_two::PowerOfTwoPolicy;
|
||||
use sgl_router::policies_reorg::{PickError, PickRequest, Policy, Stage};
|
||||
use sgl_router::state::load_monitor::engine_reported_load::{
|
||||
EngineReportedLoadTable, EngineReportedWorkerLoad, LoadStat,
|
||||
};
|
||||
use sgl_router::workers::Worker;
|
||||
|
||||
const URL: &str = "http://engine";
|
||||
|
||||
fn report(table: &EngineReportedLoadTable, rank: u32, running: u64, at: Instant) {
|
||||
table.set(
|
||||
URL,
|
||||
rank,
|
||||
LoadStat {
|
||||
num_running_reqs: running,
|
||||
num_waiting_reqs: 2,
|
||||
num_tokens: 30,
|
||||
max_total_num_tokens: 100,
|
||||
native_cache: None,
|
||||
},
|
||||
at,
|
||||
);
|
||||
}
|
||||
|
||||
fn engine() -> Arc<Worker> {
|
||||
Arc::new(Worker::new(WorkerSpec {
|
||||
id: WorkerId("a".into()),
|
||||
url: URL.into(),
|
||||
mode: Stage::Plain,
|
||||
model_ids: vec![ModelId("m".into())],
|
||||
bootstrap_port: None,
|
||||
}))
|
||||
}
|
||||
|
||||
#[derive(Debug)]
|
||||
struct ObserveAdmission {
|
||||
table: Arc<EngineReportedLoadTable>,
|
||||
observations: Mutex<Vec<Option<EngineReportedWorkerLoad>>>,
|
||||
}
|
||||
|
||||
impl EngineAdmission for ObserveAdmission {
|
||||
fn check(
|
||||
&self,
|
||||
engine: &Worker,
|
||||
_: &PickRequest<'_>,
|
||||
load: Option<&EngineReportedWorkerLoad>,
|
||||
) -> Result<Decision, PickError> {
|
||||
assert_eq!(engine.url, URL);
|
||||
// A new report arriving after selection must not change the observation
|
||||
// supplied to admission. The next pick should read the new report.
|
||||
report(&self.table, 0, 99, Instant::now());
|
||||
self.observations.lock().unwrap().push(load.cloned());
|
||||
Ok(Decision::Allow)
|
||||
}
|
||||
}
|
||||
|
||||
#[tokio::test]
|
||||
async fn selected_load_reaches_admission_and_next_pick_reads_fresh_state() {
|
||||
let table = EngineReportedLoadTable::new();
|
||||
let first_at = Instant::now();
|
||||
report(&table, 0, 1, first_at);
|
||||
report(&table, 1, 3, first_at);
|
||||
table.mark_expected_rank(URL, 0);
|
||||
table.mark_expected_rank(URL, 1);
|
||||
let admission = Arc::new(ObserveAdmission {
|
||||
table: table.clone(),
|
||||
observations: Mutex::default(),
|
||||
});
|
||||
let mut policy = PowerOfTwoPolicy::new(table);
|
||||
policy.admission = admission.clone();
|
||||
let model = ModelId("m".into());
|
||||
let request = PickRequest::new(&model, Stage::Plain, 10);
|
||||
let alternative = Arc::new(Worker::new(WorkerSpec {
|
||||
id: WorkerId("b".into()),
|
||||
url: "http://other".into(),
|
||||
mode: Stage::Plain,
|
||||
model_ids: vec![ModelId("m".into())],
|
||||
bootstrap_port: None,
|
||||
}));
|
||||
// These old-format reports lack native pressure metrics, so selection uses
|
||||
// local active counts for both candidates and chooses the second engine.
|
||||
let _busy = alternative.load_guard();
|
||||
let engines = [alternative, engine()];
|
||||
for _ in 0..2 {
|
||||
let pick = policy.pick(&engines, &request).await.unwrap();
|
||||
assert!(Arc::ptr_eq(&pick.engine, &engines[1]));
|
||||
}
|
||||
let observations = admission.observations.lock().unwrap();
|
||||
assert_eq!(observations.len(), 2);
|
||||
assert_eq!(
|
||||
observations[0],
|
||||
Some(EngineReportedWorkerLoad {
|
||||
num_running_reqs: 4,
|
||||
num_waiting_reqs: 4,
|
||||
num_tokens: 60,
|
||||
max_total_num_tokens: 200,
|
||||
captured_at: first_at,
|
||||
})
|
||||
);
|
||||
assert_eq!(observations[1].as_ref().unwrap().num_running_reqs, 102);
|
||||
}
|
||||
|
||||
#[tokio::test]
|
||||
async fn missing_stale_and_incomplete_reports_reach_admission_as_unknown() {
|
||||
for case in ["missing", "stale", "incomplete"] {
|
||||
let table = EngineReportedLoadTable::new();
|
||||
match case {
|
||||
"missing" => {}
|
||||
"stale" => report(&table, 0, 1, Instant::now() - Duration::from_secs(3600)),
|
||||
"incomplete" => {
|
||||
report(&table, 0, 1, Instant::now());
|
||||
table.mark_expected_rank(URL, 0);
|
||||
table.mark_expected_rank(URL, 1);
|
||||
}
|
||||
_ => unreachable!(),
|
||||
}
|
||||
let admission = Arc::new(ObserveAdmission {
|
||||
table: table.clone(),
|
||||
observations: Mutex::default(),
|
||||
});
|
||||
let mut policy = PowerOfTwoPolicy::new(table);
|
||||
policy.admission = admission.clone();
|
||||
let model = ModelId("m".into());
|
||||
policy
|
||||
.pick(&[engine()], &PickRequest::new(&model, Stage::Plain, 10))
|
||||
.await
|
||||
.unwrap();
|
||||
assert_eq!(*admission.observations.lock().unwrap(), [None], "{case}");
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,203 @@
|
||||
// SPDX-FileCopyrightText: Copyright (c) 2026 The SGLang Authors
|
||||
// SPDX-License-Identifier: Apache-2.0
|
||||
|
||||
use std::sync::atomic::Ordering;
|
||||
use std::sync::Arc;
|
||||
use std::time::{Duration, Instant};
|
||||
|
||||
use sgl_router::discovery::{ModelId, WorkerId, WorkerSpec};
|
||||
use sgl_router::policies_reorg::power_of_two::PowerOfTwoPolicy;
|
||||
use sgl_router::policies_reorg::{PickRequest, Policy, Stage};
|
||||
use sgl_router::state::load_monitor::engine_reported_load::{
|
||||
EngineReportedLoadTable, LoadStat, NativeCacheRankLoad,
|
||||
};
|
||||
use sgl_router::workers::Worker;
|
||||
|
||||
fn engine(id: &str, stage: Stage, active: usize) -> Arc<Worker> {
|
||||
let worker = Arc::new(Worker::new(WorkerSpec {
|
||||
id: WorkerId(id.into()),
|
||||
url: format!("http://{id}"),
|
||||
mode: stage,
|
||||
model_ids: vec![ModelId("m".into())],
|
||||
bootstrap_port: None,
|
||||
}));
|
||||
worker.active_requests.store(active, Ordering::Relaxed);
|
||||
worker
|
||||
}
|
||||
|
||||
fn load(running: u64, waiting: u64, tokens: u64, capacity: u64, pending: u64) -> LoadStat {
|
||||
LoadStat {
|
||||
num_running_reqs: running,
|
||||
num_waiting_reqs: waiting,
|
||||
num_tokens: tokens,
|
||||
max_total_num_tokens: capacity,
|
||||
native_cache: Some(NativeCacheRankLoad {
|
||||
num_waiting_uncached_tokens: pending,
|
||||
num_total_tokens: tokens,
|
||||
max_running_requests: 100,
|
||||
total_prefill_uncached_tokens: 0,
|
||||
total_prefill_busy_us: 0,
|
||||
}),
|
||||
}
|
||||
}
|
||||
|
||||
async fn assert_winner(
|
||||
policy: &PowerOfTwoPolicy,
|
||||
engines: &[Arc<Worker>],
|
||||
stage: Stage,
|
||||
expected: &Arc<Worker>,
|
||||
) {
|
||||
let model = ModelId("m".into());
|
||||
let request = PickRequest::new(&model, stage, 10);
|
||||
// With exactly two candidates the winner is independent of sample order.
|
||||
for _ in 0..16 {
|
||||
let pick = policy.pick(engines, &request).await.unwrap();
|
||||
assert!(Arc::ptr_eq(&pick.engine, expected), "stage: {stage:?}");
|
||||
assert_eq!(pick.reason, "power_of_two");
|
||||
}
|
||||
}
|
||||
|
||||
#[tokio::test]
|
||||
async fn plain_and_prefill_use_pending_work_while_decode_uses_request_pressure() {
|
||||
for stage in [Stage::Plain, Stage::Prefill, Stage::Decode] {
|
||||
let engines = [engine("a", stage, 100), engine("b", stage, 0)];
|
||||
let table = EngineReportedLoadTable::new();
|
||||
table.set(&engines[0].url, 0, load(5, 8, 10, 100, 1), Instant::now());
|
||||
table.set(&engines[1].url, 0, load(1, 1, 10, 100, 100), Instant::now());
|
||||
let expected = if stage == Stage::Decode { 1 } else { 0 };
|
||||
assert_winner(
|
||||
&PowerOfTwoPolicy::new(table),
|
||||
&engines,
|
||||
stage,
|
||||
&engines[expected],
|
||||
)
|
||||
.await;
|
||||
}
|
||||
}
|
||||
|
||||
#[tokio::test]
|
||||
async fn prefill_uses_estimated_queue_time_only_when_both_engines_have_rates() {
|
||||
for both_have_rates in [true, false] {
|
||||
let engines = [
|
||||
engine("a", Stage::Prefill, 0),
|
||||
engine("b", Stage::Prefill, 0),
|
||||
];
|
||||
let table = EngineReportedLoadTable::new();
|
||||
for (i, worker) in engines.iter().enumerate() {
|
||||
let mut report = load(1, 1, 10, 100, if i == 0 { 10 } else { 20 });
|
||||
if i == 0 || both_have_rates {
|
||||
table.set(&worker.url, 0, report.clone(), Instant::now());
|
||||
}
|
||||
let native = report.native_cache.as_mut().unwrap();
|
||||
native.total_prefill_uncached_tokens = if i == 0 { 100 } else { 1000 };
|
||||
native.total_prefill_busy_us = 1_000_000;
|
||||
table.set(&worker.url, 0, report, Instant::now());
|
||||
}
|
||||
// B has more queued tokens, but its higher throughput gives a shorter
|
||||
// estimated queue. Without B's rate, compare queued tokens for both.
|
||||
let expected = usize::from(both_have_rates);
|
||||
assert_winner(
|
||||
&PowerOfTwoPolicy::new(table),
|
||||
&engines,
|
||||
Stage::Prefill,
|
||||
&engines[expected],
|
||||
)
|
||||
.await;
|
||||
}
|
||||
}
|
||||
|
||||
#[tokio::test]
|
||||
async fn decode_orders_by_waiting_running_kv_fraction_then_tokens() {
|
||||
let cases = [
|
||||
(load(50, 1, 90, 100, 0), load(1, 2, 1, 100, 0)),
|
||||
(load(1, 1, 90, 100, 0), load(2, 1, 1, 100, 0)),
|
||||
(load(1, 1, 100, 1000, 0), load(1, 1, 20, 100, 0)),
|
||||
(load(1, 1, 10, 100, 0), load(1, 1, 100, 1000, 0)),
|
||||
];
|
||||
for (left, right) in cases {
|
||||
let engines = [
|
||||
engine("a", Stage::Decode, 100),
|
||||
engine("b", Stage::Decode, 0),
|
||||
];
|
||||
let table = EngineReportedLoadTable::new();
|
||||
table.set(&engines[0].url, 0, left, Instant::now());
|
||||
table.set(&engines[1].url, 0, right, Instant::now());
|
||||
assert_winner(
|
||||
&PowerOfTwoPolicy::new(table),
|
||||
&engines,
|
||||
Stage::Decode,
|
||||
&engines[0],
|
||||
)
|
||||
.await;
|
||||
}
|
||||
}
|
||||
|
||||
#[tokio::test]
|
||||
async fn unusable_telemetry_falls_back_to_local_load_for_both_candidates() {
|
||||
for stage in [Stage::Plain, Stage::Prefill, Stage::Decode] {
|
||||
for case in [
|
||||
"missing",
|
||||
"stale",
|
||||
"incomplete",
|
||||
"old_publisher",
|
||||
"unknown_capacity",
|
||||
] {
|
||||
let engines = [engine("a", stage, 1), engine("b", stage, 5)];
|
||||
let table = EngineReportedLoadTable::new();
|
||||
// A's high reported pressure must not be compared to B's local
|
||||
// count or to a fabricated zero for its unavailable telemetry.
|
||||
table.set(
|
||||
&engines[0].url,
|
||||
0,
|
||||
load(90, 90, 90, 100, 900),
|
||||
Instant::now(),
|
||||
);
|
||||
let mut right = load(0, 0, 0, 100, 0);
|
||||
let mut at = Instant::now();
|
||||
match case {
|
||||
"missing" => {}
|
||||
"stale" => at -= Duration::from_secs(3600),
|
||||
"incomplete" => {
|
||||
table.mark_expected_rank(&engines[1].url, 0);
|
||||
table.mark_expected_rank(&engines[1].url, 1);
|
||||
}
|
||||
"old_publisher" => right.native_cache = None,
|
||||
"unknown_capacity" => right.max_total_num_tokens = 0,
|
||||
_ => unreachable!(),
|
||||
}
|
||||
if case != "missing" {
|
||||
table.set(&engines[1].url, 0, right, at);
|
||||
}
|
||||
assert_winner(&PowerOfTwoPolicy::new(table), &engines, stage, &engines[0]).await;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
#[tokio::test]
|
||||
async fn equal_reported_pressure_uses_local_active_load_as_tiebreaker() {
|
||||
for stage in [Stage::Plain, Stage::Prefill, Stage::Decode] {
|
||||
let engines = [engine("a", stage, 5), engine("b", stage, 1)];
|
||||
let table = EngineReportedLoadTable::new();
|
||||
for worker in &engines {
|
||||
table.set(&worker.url, 0, load(1, 1, 10, 100, 10), Instant::now());
|
||||
}
|
||||
assert_winner(&PowerOfTwoPolicy::new(table), &engines, stage, &engines[1]).await;
|
||||
}
|
||||
}
|
||||
|
||||
#[tokio::test]
|
||||
async fn multiple_candidates_never_select_the_unique_busiest_engine() {
|
||||
let engines: Vec<_> = (0..8)
|
||||
.map(|i| engine(&i.to_string(), Stage::Plain, i))
|
||||
.collect();
|
||||
let policy = PowerOfTwoPolicy::new(EngineReportedLoadTable::new());
|
||||
let model = ModelId("m".into());
|
||||
let request = PickRequest::new(&model, Stage::Plain, 10);
|
||||
for _ in 0..64 {
|
||||
let pick = policy.pick(&engines, &request).await.unwrap();
|
||||
// Every distinct pair has an engine less busy than the last candidate.
|
||||
assert!(engines[..7]
|
||||
.iter()
|
||||
.any(|engine| Arc::ptr_eq(engine, &pick.engine)));
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user