test_replica_calculation.py 28.2 KB
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# SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
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# SPDX-License-Identifier: Apache-2.0

"""
Unit tests for SLA planner replica calculation logic.

These tests focus specifically on the replica calculation formulas without
testing load prediction, interpolation, or correction factors.
"""

import argparse
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import asyncio
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import math
import os
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from unittest.mock import Mock, patch
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import pytest

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from dynamo.planner.utils.decode_planner import DecodePlanner
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from dynamo.planner.utils.planner_core import (
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    PlannerSharedState,
    _apply_global_gpu_budget,
)
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from dynamo.planner.utils.prefill_planner import PrefillPlanner
from dynamo.planner.utils.prometheus import Metrics
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pytestmark = [pytest.mark.pre_merge, pytest.mark.gpu_0]

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class PlannerHarness:
    def __init__(self, prefill_planner, decode_planner, shared_state):
        self.prefill_planner = prefill_planner
        self.decode_planner = decode_planner
        self.shared_state = shared_state
        self.last_target_replicas = []

    async def make_adjustments(self):
        if not self.shared_state.last_metrics.is_valid():
            return

        p_endpoints, d_endpoints = await self.prefill_planner.get_workers_info()
        self.shared_state.p_endpoints = p_endpoints
        self.shared_state.d_endpoints = d_endpoints

        next_num_p = self.prefill_planner.plan_adjustment()
        next_num_d = self.decode_planner.plan_adjustment()
        if next_num_p is None or next_num_d is None:
            return

        next_num_p, next_num_d = _apply_global_gpu_budget(
            next_num_p, next_num_d, self.prefill_planner.args
        )
        self.prefill_planner.update_predicted_replicas_metric(next_num_p)
        self.decode_planner.update_predicted_replicas_metric(next_num_d)

        target_replicas = [
            {
                "sub_component_type": "prefill",
                "component_name": self.prefill_planner.prefill_component_name,
                "desired_replicas": next_num_p,
            },
            {
                "sub_component_type": "decode",
                "component_name": self.prefill_planner.decode_component_name,
                "desired_replicas": next_num_d,
            },
        ]
        self.last_target_replicas = target_replicas

        if not self.prefill_planner.args.no_operation:
            await self.prefill_planner.connector.set_component_replicas(
                target_replicas, blocking=False
            )

    def __getattr__(self, name):
        shared_attrs = {
            "num_req_predictor",
            "isl_predictor",
            "osl_predictor",
            "connector",
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            "prometheus_traffic_client",
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            "args",
        }
        prefill_attrs = {
            "prefill_interpolator",
            "prefill_component_name",
            "p_correction_factor",
        }
        decode_attrs = {
            "decode_interpolator",
            "decode_component_name",
            "d_correction_factor",
        }
        if name == "last_metrics":
            return self.shared_state.last_metrics
        if name == "get_workers_info":
            return self.prefill_planner.get_workers_info
        if name in shared_attrs:
            return getattr(self.prefill_planner, name)
        if name in prefill_attrs:
            return getattr(self.prefill_planner, name)
        if name in decode_attrs:
            return getattr(self.decode_planner, name)
        raise AttributeError(name)

    def __setattr__(self, name, value):
        if name in {"prefill_planner", "decode_planner", "shared_state"}:
            return super().__setattr__(name, value)
        shared_attrs = {
            "num_req_predictor",
            "isl_predictor",
            "osl_predictor",
            "connector",
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            "prometheus_traffic_client",
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            "args",
            "get_workers_info",
        }
        prefill_attrs = {"prefill_interpolator", "p_correction_factor"}
        decode_attrs = {"decode_interpolator", "d_correction_factor"}
        if name == "last_metrics":
            self.shared_state.last_metrics = value
            return None
        if name in shared_attrs:
            # Store locally to support patch.object lifecycle (set/del).
            object.__setattr__(self, name, value)
            setattr(self.prefill_planner, name, value)
            setattr(self.decode_planner, name, value)
            return None
        if name in prefill_attrs:
            setattr(self.prefill_planner, name, value)
            return None
        if name in decode_attrs:
            setattr(self.decode_planner, name, value)
            return None
        return super().__setattr__(name, value)


def _replica_count(target_replicas, component_name, default=1):
    for replica in target_replicas:
        if replica.get("component_name") == component_name:
            return replica.get("desired_replicas", default)
    return default


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@pytest.fixture
def planner():
    """Set up test environment with mocked dependencies."""
    # Create mock arguments
    args = argparse.Namespace()
    args.adjustment_interval = 60
    args.prefill_engine_num_gpu = 1
    args.decode_engine_num_gpu = 1
    args.min_endpoint = 1
    args.max_gpu_budget = 10
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    args.ttft = 80.0  # ms
    args.itl = 10.0  # ms
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    args.backend = "vllm"
    args.no_operation = True  # Don't actually scale
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    args.no_correction = False  # Allow correction factors
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    args.metric_pulling_prometheus_endpoint = "http://localhost:9090"  # dummy endpoint
    args.metric_reporting_prometheus_port = 0  # 0 means disabled
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    args.load_predictor = "constant"
    args.load_prediction_window_size = 10
    args.profile_results_dir = os.path.join(
        os.path.dirname(__file__),
        "profiling_results/H200_TP1P_TP1D",
    )
    args.environment = "kubernetes"
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    args.namespace = "test-namespace"  # Required for Planner.__init__
    args.no_correction = False  # Required for Planner.__init__
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    # Mock the runtime
    mock_runtime = Mock()

    # Patch Prometheus Gauge to avoid registry conflicts
    with patch("dynamo.planner.utils.planner_core.Gauge") as mock_gauge:
        mock_gauge.return_value = Mock()

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        shared_state = PlannerSharedState()
        prefill_planner = PrefillPlanner(mock_runtime, args, shared_state=shared_state)
        decode_planner = DecodePlanner(mock_runtime, args, shared_state=shared_state)
        planner = PlannerHarness(prefill_planner, decode_planner, shared_state)
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        # Mock the interpolators to return fixed values for testing
        planner.prefill_interpolator = Mock()
        planner.decode_interpolator = Mock()

        # Mock the predictors to return fixed values
        planner.num_req_predictor = Mock()
        planner.isl_predictor = Mock()
        planner.osl_predictor = Mock()

        # Mock the connector since we're not testing actual scaling
        planner.connector = Mock()

        # Mock prometheus client
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        planner.prometheus_traffic_client = Mock()
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        # Set up some baseline correction factors
        planner.p_correction_factor = 1.0
        planner.d_correction_factor = 1.0

        # Store args for easy access in tests
        planner.args = args

        yield planner
        # Cleanup is automatic with context manager


class TestReplicaCalculation:
    """Test replica calculation formulas in isolation."""

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    @pytest.mark.nightly
    @pytest.mark.gpu_2
    @pytest.mark.performance
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    def test_prefill_replica_calculation_basic(self, planner):
        """Test basic prefill replica calculation."""
        # Setup test data
        next_num_req = 10
        next_isl = 3000
        prefill_thpt_per_gpu = 40000  # tokens/s/gpu (from the test data)

        # Mock the predictor outputs
        planner.num_req_predictor.predict_next.return_value = next_num_req
        planner.isl_predictor.predict_next.return_value = next_isl
        planner.osl_predictor.predict_next.return_value = 150

        # Mock interpolator output
        planner.prefill_interpolator.interpolate_thpt_per_gpu.return_value = (
            prefill_thpt_per_gpu
        )
        planner.decode_interpolator.find_best_throughput_per_gpu.return_value = (
            10000,
            0.01,
            0.5,
        )

        # Calculate expected result manually
        pred_prefill_load_per_gpu = (
            next_num_req
            * next_isl
            / planner.args.adjustment_interval
            * min(1, planner.p_correction_factor)
        )
        expected_prefill_replicas = math.ceil(
            pred_prefill_load_per_gpu
            / prefill_thpt_per_gpu
            / planner.args.prefill_engine_num_gpu
        )

        # Set up valid metrics to trigger calculation
        planner.last_metrics = Metrics(
            num_req=10, isl=3000, osl=150, ttft=80.0, itl=10.0, request_duration=100.0
        )

        # Mock workers info
        async def mock_get_workers_info():
            return (["prefill1"], ["decode1"])

        planner.get_workers_info = mock_get_workers_info

        # Mock interpolation calls for correction factor calculation
        planner.prefill_interpolator.interpolate_ttft.return_value = 80.0
        planner.decode_interpolator.interpolate_itl.return_value = 10.0

        # Run the calculation
        asyncio.run(planner.make_adjustments())

        # Extract the calculated values from the log calls or by checking the mock calls
        # Since we mocked the connector, we can check what replicas were requested
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        prefill_component = "VllmPrefillWorker"
        calculated_prefill_replicas = _replica_count(
            planner.last_target_replicas, prefill_component
        )
        print(f"Expected prefill replicas: {expected_prefill_replicas}")
        print(f"Calculated prefill replicas: {calculated_prefill_replicas}")
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        # Allow for small differences due to min_endpoint constraints
        assert (
            max(expected_prefill_replicas, planner.args.min_endpoint)
            == calculated_prefill_replicas
        )
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    @pytest.mark.nightly
    @pytest.mark.gpu_2
    @pytest.mark.performance
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    def test_decode_replica_calculation_basic(self, planner):
        """Test basic decode replica calculation."""
        # Setup test data
        next_num_req = 10
        next_osl = 150
        decode_thpt_per_gpu = 10000  # tokens/s/gpu

        # Mock the predictor outputs
        planner.num_req_predictor.predict_next.return_value = next_num_req
        planner.isl_predictor.predict_next.return_value = 3000
        planner.osl_predictor.predict_next.return_value = next_osl

        # Mock interpolator outputs
        planner.prefill_interpolator.interpolate_thpt_per_gpu.return_value = 40000
        planner.decode_interpolator.find_best_throughput_per_gpu.return_value = (
            decode_thpt_per_gpu,
            0.01,
            0.5,
        )

        # Calculate expected result manually
        expected_decode_replicas = math.ceil(
            next_num_req
            * next_osl
            / planner.args.adjustment_interval
            / decode_thpt_per_gpu
            / planner.args.decode_engine_num_gpu
        )

        # Set up valid metrics
        planner.last_metrics = Metrics(
            num_req=10, isl=3000, osl=150, ttft=80.0, itl=10.0, request_duration=100.0
        )

        # Mock workers info
        async def mock_get_workers_info():
            return (["prefill1"], ["decode1"])

        planner.get_workers_info = mock_get_workers_info

        # Mock interpolation calls for correction factor calculation
        planner.prefill_interpolator.interpolate_ttft.return_value = 80.0
        planner.decode_interpolator.interpolate_itl.return_value = 10.0

        # Run the calculation
        asyncio.run(planner.make_adjustments())

        # Check the results
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        decode_component = "VllmDecodeWorker"
        calculated_decode_replicas = _replica_count(
            planner.last_target_replicas, decode_component
        )
        print(f"Expected decode replicas: {expected_decode_replicas}")
        print(f"Calculated decode replicas: {calculated_decode_replicas}")
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        # Allow for small differences due to min_endpoint constraints
        assert (
            max(expected_decode_replicas, planner.args.min_endpoint)
            == calculated_decode_replicas
        )
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    @pytest.mark.parametrize(
        "num_req,decode_thpt,expected_p,expected_d",
        [
            (10, 10000, 1, 1),  # low_load_10_req_per_second
            (500, 1000, 1, 2),  # high_load_500_req_per_second (lower decode throughput)
        ],
    )
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    @pytest.mark.nightly
    @pytest.mark.gpu_2
    @pytest.mark.performance
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    def test_scaling_scenario_low_to_high_load(
        self, planner, num_req, decode_thpt, expected_p, expected_d
    ):
        """Test scaling from low to high load scenarios."""
        # Reset the planner state
        planner.p_correction_factor = 1.0
        planner.d_correction_factor = 1.0

        # Mock predictor outputs for this case
        planner.num_req_predictor.predict_next.return_value = num_req
        planner.isl_predictor.predict_next.return_value = 3000
        planner.osl_predictor.predict_next.return_value = 150

        # Mock interpolator outputs (based on H200 1P1D profiling data)
        planner.prefill_interpolator.interpolate_thpt_per_gpu.return_value = (
            40000  # tokens/s/gpu
        )
        planner.decode_interpolator.find_best_throughput_per_gpu.return_value = (
            decode_thpt,
            0.01,
            0.5,
        )

        # Set up metrics
        planner.last_metrics = Metrics(
            num_req=num_req,
            isl=3000,
            osl=150,
            ttft=80.0,
            itl=10.0,
            request_duration=100.0,
        )

        # Mock workers info
        async def mock_get_workers_info():
            return (["prefill1"], ["decode1"])

        planner.get_workers_info = mock_get_workers_info

        # Mock interpolation calls for correction factor calculation
        planner.prefill_interpolator.interpolate_ttft.return_value = 80.0
        planner.decode_interpolator.interpolate_itl.return_value = 10.0

        # Reset the mock
        planner.connector.reset_mock()

        # Run calculation
        asyncio.run(planner.make_adjustments())

        # Verify results
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        prefill_replicas = _replica_count(
            planner.last_target_replicas, "VllmPrefillWorker"
        )
        decode_replicas = _replica_count(
            planner.last_target_replicas, "VllmDecodeWorker"
        )
        print(f"Load {num_req} req/s: P={prefill_replicas}, D={decode_replicas}")
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        assert (
            prefill_replicas == expected_p
        ), f"Prefill replicas mismatch: expected {expected_p}, got {prefill_replicas}"
        assert (
            decode_replicas == expected_d
        ), f"Decode replicas mismatch: expected {expected_d}, got {decode_replicas}"
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    @pytest.mark.nightly
    @pytest.mark.gpu_2
    @pytest.mark.performance
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    def test_gpu_budget_constraint(self, planner):
        """Test that GPU budget constraints are properly applied."""
        # Set a low GPU budget
        planner.args.max_gpu_budget = 3

        # Mock predictor outputs that would normally require more GPUs
        planner.num_req_predictor.predict_next.return_value = 50  # High load
        planner.isl_predictor.predict_next.return_value = 3000
        planner.osl_predictor.predict_next.return_value = 150

        # Mock interpolator outputs
        planner.prefill_interpolator.interpolate_thpt_per_gpu.return_value = 40000
        planner.decode_interpolator.find_best_throughput_per_gpu.return_value = (
            10000,
            0.01,
            0.5,
        )

        # Set up metrics
        planner.last_metrics = Metrics(
            num_req=50, isl=3000, osl=150, ttft=80.0, itl=10.0, request_duration=100.0
        )

        # Mock workers info
        async def mock_get_workers_info():
            return (["prefill1"], ["decode1"])

        planner.get_workers_info = mock_get_workers_info

        # Mock interpolation calls
        planner.prefill_interpolator.interpolate_ttft.return_value = 80.0
        planner.decode_interpolator.interpolate_itl.return_value = 10.0

        # Run calculation
        asyncio.run(planner.make_adjustments())

        # Verify that total GPU usage doesn't exceed budget
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        prefill_replicas = _replica_count(
            planner.last_target_replicas, "VllmPrefillWorker"
        )
        decode_replicas = _replica_count(
            planner.last_target_replicas, "VllmDecodeWorker"
        )
        total_gpus = (
            prefill_replicas * planner.args.prefill_engine_num_gpu
            + decode_replicas * planner.args.decode_engine_num_gpu
        )
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        print(
            f"GPU budget test: P={prefill_replicas}, D={decode_replicas}, Total GPUs={total_gpus}"
        )
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        assert (
            total_gpus <= planner.args.max_gpu_budget
        ), "Total GPU usage exceeds budget"
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    @pytest.mark.nightly
    @pytest.mark.gpu_2
    @pytest.mark.performance
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    def test_min_endpoint_constraint(self, planner):
        """Test that minimum endpoint constraints are respected."""
        planner.args.min_endpoint = 2

        # Mock predictor outputs that would normally require fewer workers
        planner.num_req_predictor.predict_next.return_value = 1  # Very low load
        planner.isl_predictor.predict_next.return_value = 100
        planner.osl_predictor.predict_next.return_value = 10

        # Mock interpolator outputs
        planner.prefill_interpolator.interpolate_thpt_per_gpu.return_value = 40000
        planner.decode_interpolator.find_best_throughput_per_gpu.return_value = (
            10000,
            0.01,
            0.5,
        )

        # Set up metrics
        planner.last_metrics = Metrics(
            num_req=1, isl=100, osl=10, ttft=80.0, itl=10.0, request_duration=100.0
        )

        # Mock workers info
        async def mock_get_workers_info():
            return (["prefill1"], ["decode1"])

        planner.get_workers_info = mock_get_workers_info

        # Mock interpolation calls
        planner.prefill_interpolator.interpolate_ttft.return_value = 80.0
        planner.decode_interpolator.interpolate_itl.return_value = 10.0

        # Run calculation
        asyncio.run(planner.make_adjustments())

        # Verify minimum constraints are respected
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        prefill_replicas = _replica_count(
            planner.last_target_replicas, "VllmPrefillWorker"
        )
        decode_replicas = _replica_count(
            planner.last_target_replicas, "VllmDecodeWorker"
        )
        print(f"Min endpoint test: P={prefill_replicas}, D={decode_replicas}")
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        assert (
            prefill_replicas >= planner.args.min_endpoint
        ), "Prefill replicas below minimum"
        assert (
            decode_replicas >= planner.args.min_endpoint
        ), "Decode replicas below minimum"
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    @pytest.mark.nightly
    @pytest.mark.gpu_2
    @pytest.mark.performance
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    def test_prefill_correction_factor_clamping(self, planner):
        """Test that prefill correction factor > 1 is clamped to 1."""
        # Set a high correction factor > 1
        planner.p_correction_factor = 2.5
        planner.d_correction_factor = 1.0

        # Mock predictor outputs
        planner.num_req_predictor.predict_next.return_value = 10
        planner.isl_predictor.predict_next.return_value = 3000
        planner.osl_predictor.predict_next.return_value = 150

        # Mock interpolator outputs
        planner.prefill_interpolator.interpolate_thpt_per_gpu.return_value = 40000
        planner.decode_interpolator.find_best_throughput_per_gpu.return_value = (
            10000,
            0.01,
            0.5,
        )

        # Set up metrics
        planner.last_metrics = Metrics(
            num_req=10, isl=3000, osl=150, ttft=80.0, itl=10.0, request_duration=100.0
        )

        # Mock workers info
        async def mock_get_workers_info():
            return (["prefill1"], ["decode1"])

        planner.get_workers_info = mock_get_workers_info

        # Mock interpolation calls
        planner.prefill_interpolator.interpolate_ttft.return_value = 80.0
        planner.decode_interpolator.interpolate_itl.return_value = 10.0

        # Calculate expected result manually with clamping
        # Should use min(1, 2.5) = 1
        pred_prefill_load_per_gpu = (
            10 * 3000 / planner.args.adjustment_interval * min(1, 2.5)  # Should be * 1
        )
        expected_prefill_replicas = math.ceil(
            pred_prefill_load_per_gpu / 40000 / planner.args.prefill_engine_num_gpu
        )

        # Run calculation
        asyncio.run(planner.make_adjustments())

        # Verify that correction factor was effectively clamped
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        prefill_replicas = _replica_count(
            planner.last_target_replicas, "VllmPrefillWorker"
        )
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        print(
            f"Correction factor clamping test: Expected={expected_prefill_replicas}, Got={prefill_replicas}"
        )
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        assert prefill_replicas == max(
            expected_prefill_replicas, planner.args.min_endpoint
        ), "Prefill correction factor should be clamped to 1"
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    @pytest.mark.nightly
    @pytest.mark.gpu_2
    @pytest.mark.performance
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    def test_decode_correction_factor_zero_handling(self, planner):
        """Test handling of d_correction_factor <= 0."""
        # Test both 0 and negative values
        for correction_factor in [0.0, -1.0]:
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            planner.p_correction_factor = 1.0
            planner.d_correction_factor = correction_factor

            # Mock predictor outputs
            planner.num_req_predictor.predict_next.return_value = 10
            planner.isl_predictor.predict_next.return_value = 3000
            planner.osl_predictor.predict_next.return_value = 150

            # Mock interpolator outputs
            planner.prefill_interpolator.interpolate_thpt_per_gpu.return_value = 40000
            planner.decode_interpolator.find_best_throughput_per_gpu.return_value = (
                10000,
                0.01,
                0.5,
            )

            # Set up metrics
            planner.last_metrics = Metrics(
                num_req=10,
                isl=3000,
                osl=150,
                ttft=80.0,
                itl=10.0,
                request_duration=100.0,
            )

            # Mock workers info
            async def mock_get_workers_info():
                return (["prefill1"], ["decode1"])

            planner.get_workers_info = mock_get_workers_info

            # Mock interpolation calls
            planner.prefill_interpolator.interpolate_ttft.return_value = 80.0
            planner.decode_interpolator.interpolate_itl.return_value = 10.0

            # Run calculation
            asyncio.run(planner.make_adjustments())

            # Should handle gracefully without crashing
            # The code should use args.itl directly instead of dividing by 0
            decode_replicas = _replica_count(
                planner.last_target_replicas, "VllmDecodeWorker"
            )

            print(
                f"Correction factor {correction_factor} test: Decode replicas={decode_replicas}"
            )

            # Should get a valid result (not crash)
            assert (
                decode_replicas >= 1
            ), f"Should handle correction factor {correction_factor} gracefully"
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    @pytest.mark.nightly
    @pytest.mark.gpu_2
    @pytest.mark.performance
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    def test_multi_gpu_engines(self, planner):
        """Test replica calculation with multi-GPU engines."""
        # Set multi-GPU configuration
        planner.args.prefill_engine_num_gpu = 2
        planner.args.decode_engine_num_gpu = 4

        # Mock predictor outputs
        planner.num_req_predictor.predict_next.return_value = 20
        planner.isl_predictor.predict_next.return_value = 3000
        planner.osl_predictor.predict_next.return_value = 150

        # Mock interpolator outputs
        planner.prefill_interpolator.interpolate_thpt_per_gpu.return_value = 40000
        planner.decode_interpolator.find_best_throughput_per_gpu.return_value = (
            5000,
            0.01,
            0.5,
        )  # Lower for scaling

        # Set up metrics
        planner.last_metrics = Metrics(
            num_req=20, isl=3000, osl=150, ttft=80.0, itl=10.0, request_duration=100.0
        )

        # Mock workers info
        async def mock_get_workers_info():
            return (["prefill1"], ["decode1"])

        planner.get_workers_info = mock_get_workers_info

        # Mock interpolation calls
        planner.prefill_interpolator.interpolate_ttft.return_value = 80.0
        planner.decode_interpolator.interpolate_itl.return_value = 10.0

        # Calculate expected results manually
        pred_prefill_load_per_gpu = 20 * 3000 / planner.args.adjustment_interval * 1.0
        expected_prefill_replicas = math.ceil(
            pred_prefill_load_per_gpu / 40000 / 2
        )  # 2 GPUs per engine

        expected_decode_replicas = math.ceil(
            20 * 150 / planner.args.adjustment_interval / 5000 / 4
        )  # 4 GPUs per engine

        # Run calculation
        asyncio.run(planner.make_adjustments())

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        prefill_replicas = _replica_count(
            planner.last_target_replicas, "VllmPrefillWorker"
        )
        decode_replicas = _replica_count(
            planner.last_target_replicas, "VllmDecodeWorker"
        )
        print(
            f"Multi-GPU test: P={prefill_replicas} (expected ~{expected_prefill_replicas}), D={decode_replicas} (expected ~{expected_decode_replicas})"
        )
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        # Verify calculations account for multiple GPUs per engine
        assert prefill_replicas == max(
            expected_prefill_replicas, planner.args.min_endpoint
        )
        assert decode_replicas == max(
            expected_decode_replicas, planner.args.min_endpoint
        )
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    @pytest.mark.weekly
    @pytest.mark.gpu_2
    @pytest.mark.performance
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    def test_complex_gpu_budget_scaling(self, planner):
        """Test complex GPU budget scaling with proportional reduction and decode adjustment."""
        # Set tight GPU budget that will trigger complex scaling
        planner.args.max_gpu_budget = 5
        planner.args.prefill_engine_num_gpu = 2
        planner.args.decode_engine_num_gpu = 2
        planner.args.min_endpoint = 1

        # High load that would normally require more GPUs
        planner.num_req_predictor.predict_next.return_value = 100
        planner.isl_predictor.predict_next.return_value = 3000
        planner.osl_predictor.predict_next.return_value = 150

        # Lower throughput to trigger higher replica needs
        planner.prefill_interpolator.interpolate_thpt_per_gpu.return_value = 10000
        planner.decode_interpolator.find_best_throughput_per_gpu.return_value = (
            1000,
            0.01,
            0.5,
        )

        # Set up metrics
        planner.last_metrics = Metrics(
            num_req=100, isl=3000, osl=150, ttft=80.0, itl=10.0, request_duration=100.0
        )

        # Mock workers info
        async def mock_get_workers_info():
            return (["prefill1"], ["decode1"])

        planner.get_workers_info = mock_get_workers_info

        # Mock interpolation calls
        planner.prefill_interpolator.interpolate_ttft.return_value = 80.0
        planner.decode_interpolator.interpolate_itl.return_value = 10.0

        # Run calculation
        asyncio.run(planner.make_adjustments())

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        prefill_replicas = _replica_count(
            planner.last_target_replicas, "VllmPrefillWorker"
        )
        decode_replicas = _replica_count(
            planner.last_target_replicas, "VllmDecodeWorker"
        )
        # Verify total GPU usage doesn't exceed budget
        total_gpus = (
            prefill_replicas * planner.args.prefill_engine_num_gpu
            + decode_replicas * planner.args.decode_engine_num_gpu
        )
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        print(
            f"Complex GPU budget test: P={prefill_replicas}, D={decode_replicas}, Total GPUs={total_gpus}"
        )
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        assert (
            total_gpus <= planner.args.max_gpu_budget
        ), "Total GPU usage should not exceed budget"
        assert (
            prefill_replicas >= planner.args.min_endpoint
        ), "Should respect min_endpoint for prefill"
        assert (
            decode_replicas >= planner.args.min_endpoint
        ), "Should respect min_endpoint for decode"
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# No need for unittest.main() with pytest!