Files
agentic-pd-hybrid/third_party/sglang/sgl-model-gateway/tests/reliability/fault_tolerance_test.rs

310 lines
9.3 KiB
Rust

//! Fault tolerance integration tests
//!
//! Tests for system resilience: worker failures, network issues, and recovery.
use std::sync::{
atomic::{AtomicUsize, Ordering},
Arc,
};
use axum::{
body::Body,
extract::Request,
http::{header::CONTENT_TYPE, StatusCode},
};
use serde_json::json;
use smg::config::{CircuitBreakerConfig, RetryConfig};
use tower::ServiceExt;
use crate::common::{AppTestContext, TestRouterConfig, TestWorkerConfig};
#[cfg(test)]
mod fault_tolerance_tests {
use super::*;
/// Test that requests are rerouted when a worker fails
#[tokio::test]
async fn test_worker_failure_reroute() {
let config = TestRouterConfig::round_robin_with_reliability(
4100,
RetryConfig {
max_retries: 3,
initial_backoff_ms: 10,
max_backoff_ms: 100,
..Default::default()
},
CircuitBreakerConfig {
failure_threshold: 2,
success_threshold: 1,
timeout_duration_secs: 2,
window_duration_secs: 10,
},
);
let ctx = AppTestContext::new_with_config(
config,
vec![
TestWorkerConfig::flaky(20100, 1.0), // Always fails
TestWorkerConfig::healthy(20101), // Always succeeds
],
)
.await;
let app = ctx.create_app().await;
// Requests should succeed via retry to healthy worker
for i in 0..10 {
let payload = json!({
"text": format!("Fault tolerance test {}", i),
"stream": false
});
let req = Request::builder()
.method("POST")
.uri("/generate")
.header(CONTENT_TYPE, "application/json")
.body(Body::from(serde_json::to_string(&payload).unwrap()))
.unwrap();
let resp = app.clone().oneshot(req).await.unwrap();
assert_eq!(
resp.status(),
StatusCode::OK,
"Request should succeed via reroute to healthy worker"
);
}
ctx.shutdown().await;
}
/// Test behavior when all workers are temporarily unavailable
#[tokio::test]
async fn test_all_workers_temporarily_failing() {
let config = TestRouterConfig::round_robin_with_retry(
4101,
RetryConfig {
max_retries: 2,
initial_backoff_ms: 10,
max_backoff_ms: 50,
..Default::default()
},
);
let ctx = AppTestContext::new_with_config(
config,
vec![
TestWorkerConfig::flaky(20102, 1.0), // Always fails
TestWorkerConfig::flaky(20103, 1.0), // Always fails
],
)
.await;
let app = ctx.create_app().await;
let payload = json!({
"text": "Test with all failing workers",
"stream": false
});
let req = Request::builder()
.method("POST")
.uri("/generate")
.header(CONTENT_TYPE, "application/json")
.body(Body::from(serde_json::to_string(&payload).unwrap()))
.unwrap();
let resp = app.oneshot(req).await.unwrap();
// Should fail when all workers are failing
assert!(
resp.status() == StatusCode::INTERNAL_SERVER_ERROR
|| resp.status() == StatusCode::SERVICE_UNAVAILABLE,
"Request should fail when all workers are failing, got {}",
resp.status()
);
ctx.shutdown().await;
}
/// Test graceful handling of slow workers
#[tokio::test]
async fn test_slow_worker_handling() {
let config = TestRouterConfig::round_robin(4102);
let ctx = AppTestContext::new_with_config(
config,
vec![
TestWorkerConfig::slow(20104, 500), // Slow worker
TestWorkerConfig::healthy(20105), // Fast worker
],
)
.await;
let app = ctx.create_app().await;
// Send concurrent requests
let mut handles = Vec::new();
let success_count = Arc::new(AtomicUsize::new(0));
for i in 0..10 {
let app_clone = app.clone();
let success_clone = Arc::clone(&success_count);
let handle = tokio::spawn(async move {
let payload = json!({
"text": format!("Slow worker test {}", i),
"stream": false
});
let req = Request::builder()
.method("POST")
.uri("/generate")
.header(CONTENT_TYPE, "application/json")
.body(Body::from(serde_json::to_string(&payload).unwrap()))
.unwrap();
let resp = app_clone.oneshot(req).await.unwrap();
if resp.status() == StatusCode::OK {
success_clone.fetch_add(1, Ordering::SeqCst);
}
});
handles.push(handle);
}
for handle in handles {
handle.await.unwrap();
}
// All requests should eventually succeed
assert_eq!(
success_count.load(Ordering::SeqCst),
10,
"All requests should succeed despite slow worker"
);
ctx.shutdown().await;
}
/// Test circuit breaker prevents cascading failures
#[tokio::test]
async fn test_circuit_breaker_prevents_cascade() {
let config = TestRouterConfig::round_robin_with_reliability(
4103,
RetryConfig {
max_retries: 3,
initial_backoff_ms: 10,
max_backoff_ms: 50,
..Default::default()
},
CircuitBreakerConfig {
failure_threshold: 2,
success_threshold: 1,
timeout_duration_secs: 5,
window_duration_secs: 10,
},
);
let ctx = AppTestContext::new_with_config(
config,
vec![
TestWorkerConfig::flaky(20106, 1.0), // Failing worker
TestWorkerConfig::healthy(20107), // Healthy worker
],
)
.await;
let app = ctx.create_app().await;
let mut success_count = 0;
// Send many requests - after CB opens, all should route to healthy worker
for i in 0..20 {
let payload = json!({
"text": format!("Circuit breaker cascade test {}", i),
"stream": false
});
let req = Request::builder()
.method("POST")
.uri("/generate")
.header(CONTENT_TYPE, "application/json")
.body(Body::from(serde_json::to_string(&payload).unwrap()))
.unwrap();
let resp = app.clone().oneshot(req).await.unwrap();
if resp.status() == StatusCode::OK {
success_count += 1;
}
}
// Most requests should succeed after CB opens on failing worker
assert!(
success_count >= 15,
"Most requests should succeed after circuit breaker opens, got {} successes",
success_count
);
ctx.shutdown().await;
}
/// Test recovery after worker comes back online (simulated via healthy worker)
#[tokio::test]
async fn test_system_stability_under_partial_failure() {
let config = TestRouterConfig::round_robin_with_reliability(
4104,
RetryConfig {
max_retries: 2,
initial_backoff_ms: 10,
max_backoff_ms: 50,
..Default::default()
},
CircuitBreakerConfig {
failure_threshold: 3,
success_threshold: 1,
timeout_duration_secs: 2,
window_duration_secs: 10,
},
);
let ctx = AppTestContext::new_with_config(
config,
vec![
TestWorkerConfig::flaky(20108, 0.5), // 50% failure rate
TestWorkerConfig::healthy(20109), // Always succeeds
],
)
.await;
let app = ctx.create_app().await;
let mut success_count = 0;
// System should maintain stability with partial failures
for i in 0..30 {
let payload = json!({
"text": format!("Stability test {}", i),
"stream": false
});
let req = Request::builder()
.method("POST")
.uri("/generate")
.header(CONTENT_TYPE, "application/json")
.body(Body::from(serde_json::to_string(&payload).unwrap()))
.unwrap();
let resp = app.clone().oneshot(req).await.unwrap();
if resp.status() == StatusCode::OK {
success_count += 1;
}
}
// With retries and one healthy worker, most should succeed
assert!(
success_count >= 25,
"System should maintain stability under partial failure, got {} successes",
success_count
);
ctx.shutdown().await;
}
}