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from __future__ import annotations

import sys
import unittest
import os
from pathlib import Path


ROOT = Path(__file__).resolve().parents[1]
WORKSPACE = ROOT.parent
os.environ.setdefault("MPLCONFIGDIR", "/tmp/matplotlib")
os.environ.setdefault("XDG_CACHE_HOME", "/tmp")
sys.path.insert(0, str(ROOT))
sys.path.insert(0, str(WORKSPACE / "pp-scheduler"))

from pp_scheduler import (  # noqa: E402
    BigMac,
    BigMacVPP,
    DistTrainEncoder1F1B,
    DistTrain1F1B,
    GPipe,
    OpType,
    UnifiedBigMacVPP,
    VPP1F1BSchedule,
)
from pp_simulator import OpDurationSpec, PipelineSimulator  # noqa: E402
from web.app import run_comparison  # noqa: E402


class PipelineSimulatorTest(unittest.TestCase):
    def test_gpipe_fixed_duration_result_is_valid(self):
        scheduler = GPipe(pp_size=2, num_microbatches=4)
        scheduler.generate_schedule()

        simulator = PipelineSimulator.from_scheduler(scheduler)
        result = simulator.simulate(
            {
                OpType.FORWARD: OpDurationSpec(mean=1.0),
                OpType.BACKWARD: OpDurationSpec(mean=2.0),
            },
            seed=1,
        )

        simulator.validate_result(result)
        self.assertGreater(result.summary["makespan"], 0.0)
        self.assertEqual(result.metadata["op_count"], 16)

    def test_vpp_dependencies_are_valid(self):
        scheduler = VPP1F1BSchedule(pp_size=2, vpp_size=2, num_microbatches=4)
        scheduler.generate_schedule()

        simulator = PipelineSimulator.from_scheduler(scheduler)
        result = simulator.simulate(
            {
                "F": OpDurationSpec(mean=1.0, variance=0.01),
                "B": OpDurationSpec(mean=2.0, variance=0.01),
            },
            seed=2,
        )

        simulator.validate_result(result)
        self.assertEqual(result.metadata["vpp_size"], 2)

    def test_chrome_trace_export(self):
        scheduler = GPipe(pp_size=2, num_microbatches=2)
        scheduler.generate_schedule()

        simulator = PipelineSimulator.from_scheduler(scheduler)
        result = simulator.simulate(
            {
                OpType.FORWARD: OpDurationSpec(mean=1.0),
                OpType.BACKWARD: OpDurationSpec(mean=2.0),
            }
        )

        trace = result.to_chrome_trace_dict()
        complete_events = [event for event in trace["traceEvents"] if event["ph"] == "X"]
        thread_name_events = [
            event
            for event in trace["traceEvents"]
            if event["ph"] == "M" and event["name"] == "thread_name"
        ]

        self.assertEqual(len(complete_events), result.metadata["op_count"])
        self.assertEqual(len(thread_name_events), 2)
        self.assertIn("summary", trace)
        self.assertEqual(complete_events[0]["pid"], 1)
        self.assertIn(complete_events[0]["tid"], {1, 2})
        self.assertIn("batch_id", complete_events[0]["args"])
        self.assertIn("dep_reasons", complete_events[0]["args"])

    def test_chrome_trace_keeps_pp4_vpp2_f3_c0_and_chunk_categories(self):
        scheduler = UnifiedBigMacVPP(pp_size=4, vpp_size=2, num_microbatches=8, ve_forward_limit=3)
        scheduler.generate_schedule()

        simulator = PipelineSimulator.from_scheduler(scheduler)
        result = simulator.simulate(_default_specs())
        trace = result.to_chrome_trace_dict()
        complete_events = [event for event in trace["traceEvents"] if event["ph"] == "X"]

        f3_c0_events = [event for event in complete_events if event["name"] == "F3-C0"]
        self.assertEqual(len(f3_c0_events), 4)
        self.assertEqual({event["args"]["pp_rank"] for event in f3_c0_events}, {0, 1, 2, 3})

        f0_c0 = next(event for event in complete_events if event["name"] == "F0-C0")
        f0_c1 = next(event for event in complete_events if event["name"] == "F0-C1")
        self.assertEqual(f0_c0["cat"], "F/chunk_a")
        self.assertEqual(f0_c1["cat"], "F/chunk_b")
        self.assertNotEqual(f0_c0["cat"], f0_c1["cat"])

    def test_perfetto_compat_trace_uses_unique_event_names(self):
        scheduler = UnifiedBigMacVPP(pp_size=4, vpp_size=2, num_microbatches=8, ve_forward_limit=3)
        scheduler.generate_schedule()

        simulator = PipelineSimulator.from_scheduler(scheduler)
        result = simulator.simulate(_default_specs())
        trace = result.to_chrome_trace_dict(perfetto_compat=True)
        complete_events = [event for event in trace["traceEvents"] if event["ph"] == "X"]

        f3_c0_events = [
            event
            for event in complete_events
            if event["args"]["label"] == "F3-C0"
        ]
        self.assertEqual(len(f3_c0_events), 4)
        self.assertEqual(
            {event["name"] for event in f3_c0_events},
            {
                "rank0/F/chunk_a/mb3",
                "rank1/F/chunk_a/mb3",
                "rank2/F/chunk_a/mb3",
                "rank3/F/chunk_a/mb3",
            },
        )

    def test_monte_carlo_report_statistics(self):
        scheduler = GPipe(pp_size=2, num_microbatches=2)
        scheduler.generate_schedule()

        simulator = PipelineSimulator.from_scheduler(scheduler)
        report = simulator.monte_carlo(
            {
                OpType.FORWARD: OpDurationSpec(mean=1.0, variance=0.01),
                OpType.BACKWARD: OpDurationSpec(mean=2.0, variance=0.01),
            },
            num_trials=5,
            seed=11,
            validate=True,
        )

        self.assertEqual(report.metadata["num_trials"], 5)
        self.assertEqual(len(report.trial_summaries), 5)
        self.assertEqual(report.statistics["makespan"]["count"], 5)
        self.assertIn("0", report.statistics["rank_utilization"])
        self.assertIn("F", report.statistics["op_type_time"])

    def test_monte_carlo_fixed_duration_has_zero_makespan_std(self):
        scheduler = GPipe(pp_size=2, num_microbatches=2)
        scheduler.generate_schedule()

        simulator = PipelineSimulator.from_scheduler(scheduler)
        report = simulator.monte_carlo(
            {
                OpType.FORWARD: OpDurationSpec(mean=1.0),
                OpType.BACKWARD: OpDurationSpec(mean=2.0),
            },
            num_trials=3,
            seed=3,
        )

        self.assertEqual(report.statistics["makespan"]["std"], 0.0)
        self.assertEqual(report.statistics["makespan"]["min"], report.statistics["makespan"]["max"])

    def test_monte_carlo_rejects_non_positive_trial_count(self):
        scheduler = GPipe(pp_size=2, num_microbatches=2)
        scheduler.generate_schedule()

        simulator = PipelineSimulator.from_scheduler(scheduler)
        with self.assertRaises(ValueError):
            simulator.monte_carlo(
                {
                    OpType.FORWARD: OpDurationSpec(mean=1.0),
                    OpType.BACKWARD: OpDurationSpec(mean=2.0),
                },
                num_trials=0,
            )

    def test_bigmac_llm_forward_waits_for_ve_unit(self):
        scheduler = BigMac(pp_size=2, num_microbatches=4, ve_forward_limit=3)
        scheduler.generate_schedule()

        simulator = PipelineSimulator.from_scheduler(scheduler)
        target = _find_op(simulator, rank=0, op_type="F", microbatch_id=0, chunk_id=None)
        vf0 = _find_op(simulator, rank=0, op_type="VF", microbatch_id=0, chunk_id=None)
        vf1 = _find_op(simulator, rank=1, op_type="VF", microbatch_id=1, chunk_id=None)

        reasons = simulator.graph.dependency_reasons[target.id]
        self.assertIn("ve_forward_ready", reasons[vf0.id])
        self.assertNotIn(vf1.id, reasons)

    def test_bigmac_llm_forward_waits_only_for_matching_ve_forward(self):
        scheduler = BigMac(
            pp_size=4,
            num_microbatches=16,
            ve_forward_limit=3,
            check_ve_forward_limit=False,
        )
        scheduler.generate_schedule()

        simulator = PipelineSimulator.from_scheduler(scheduler)
        f12 = _find_op(simulator, rank=0, op_type="F", microbatch_id=12, chunk_id=None)
        vf12 = _find_op(simulator, rank=0, op_type="VF", microbatch_id=12, chunk_id=None)
        peer_vfs = [
            _find_op(simulator, rank=rank, op_type="VF", microbatch_id=12 + rank, chunk_id=None)
            for rank in range(1, 4)
        ]

        reasons = simulator.graph.dependency_reasons[f12.id]
        self.assertIn("ve_forward_ready", reasons[vf12.id])
        for peer_vf in peer_vfs:
            self.assertNotIn(peer_vf.id, reasons)

    def test_bigmac_low_ve_forward_limit_exposes_bubbles(self):
        scheduler = BigMac(
            pp_size=4,
            num_microbatches=16,
            ve_forward_limit=2,
            check_ve_forward_limit=False,
        )
        scheduler.generate_schedule()

        simulator = PipelineSimulator.from_scheduler(scheduler)
        result = simulator.simulate(_default_specs(), seed=23)
        simulator.validate_result(result)

        idle_counts = {
            rank: sum(1 for op in ops if op.op_type == OpType.IDLE)
            for rank, ops in scheduler.schedules.items()
        }
        self.assertGreater(sum(idle_counts.values()), 0)

    def test_bigmac_low_ve_forward_limit_interleaves_ve_backward_before_next_ve_forward(self):
        scheduler = BigMac(
            pp_size=4,
            num_microbatches=16,
            ve_forward_limit=3,
            check_ve_forward_limit=False,
        )
        scheduler.generate_schedule()

        rank0_ops = [
            str(op)
            for op in scheduler.schedules[0]
            if op.op_type != OpType.IDLE
        ]

        self.assertLess(rank0_ops.index("B8"), rank0_ops.index("VB0"))
        self.assertEqual(rank0_ops[rank0_ops.index("VB0") + 1], "VF12")
        self.assertLess(rank0_ops.index("VF12"), rank0_ops.index("B9"))

    def test_bigmac_vpp_chunk_wrap_dependencies(self):
        scheduler = BigMacVPP(pp_size=2, vpp_size=2, num_microbatches=4, ve_forward_limit=3)
        scheduler.generate_schedule()

        simulator = PipelineSimulator.from_scheduler(scheduler)
        f_rank0_chunk1 = _find_op(simulator, rank=0, op_type="F", microbatch_id=0, chunk_id=1)
        f_rank1_chunk0 = _find_op(simulator, rank=1, op_type="F", microbatch_id=0, chunk_id=0)
        b_rank1_chunk0 = _find_op(simulator, rank=1, op_type="B", microbatch_id=0, chunk_id=0)
        b_rank0_chunk1 = _find_op(simulator, rank=0, op_type="B", microbatch_id=0, chunk_id=1)

        reasons = simulator.graph.dependency_reasons
        self.assertIn("vpp_forward_from_previous_chunk", reasons[f_rank0_chunk1.id][f_rank1_chunk0.id])
        self.assertIn("vpp_backward_from_next_chunk", reasons[b_rank1_chunk0.id][b_rank0_chunk1.id])

    def test_unified_generator_dependencies_use_matching_microbatch(self):
        scheduler = UnifiedBigMacVPP(pp_size=2, vpp_size=2, num_microbatches=4, ve_forward_limit=3)
        scheduler.generate_schedule()

        simulator = PipelineSimulator.from_scheduler(scheduler)
        gf0 = _find_op(simulator, rank=0, op_type="GF", microbatch_id=0, chunk_id=1)
        gb0 = _find_op(simulator, rank=0, op_type="GB", microbatch_id=0, chunk_id=0)
        b_last = _find_op(simulator, rank=1, op_type="B", microbatch_id=0, chunk_id=1)
        final_f0 = _find_op(simulator, rank=1, op_type="F", microbatch_id=0, chunk_id=1)
        final_f1 = _find_op(simulator, rank=1, op_type="F", microbatch_id=1, chunk_id=1)
        gb1 = _find_op(simulator, rank=1, op_type="GB", microbatch_id=1, chunk_id=0)

        reasons = simulator.graph.dependency_reasons
        self.assertIn("llm_output_ready", reasons[gf0.id][final_f0.id])
        self.assertNotIn(final_f1.id, reasons[gf0.id])
        self.assertIn("generator_backward_consumes_forward", reasons[gb0.id][gf0.id])
        self.assertNotIn(gb1.id, reasons[gb0.id])
        self.assertIn("generator_backward_ready", reasons[b_last.id][gb0.id])
        self.assertNotIn(gb1.id, reasons[b_last.id])

    def test_unified_generator_backward_does_not_wait_for_peer_generator_forward(self):
        scheduler = UnifiedBigMacVPP(pp_size=4, vpp_size=2, num_microbatches=8, ve_forward_limit=3)
        scheduler.generate_schedule()

        simulator = PipelineSimulator.from_scheduler(scheduler)
        gb4 = _find_op(simulator, rank=0, op_type="GB", microbatch_id=4, chunk_id=0)
        gf4 = _find_op(simulator, rank=0, op_type="GF", microbatch_id=4, chunk_id=1)
        peer_gfs = [
            _find_op(simulator, rank=rank, op_type="GF", microbatch_id=4 + rank, chunk_id=1)
            for rank in range(1, 4)
        ]

        reasons = simulator.graph.dependency_reasons[gb4.id]
        self.assertIn("generator_backward_consumes_forward", reasons[gf4.id])
        for peer_gf in peer_gfs:
            self.assertNotIn(peer_gf.id, reasons)

    def test_bigmac_ve_backward_waits_only_for_matching_llm_backward(self):
        scheduler = BigMac(
            pp_size=4,
            num_microbatches=32,
            ve_forward_limit=3,
            check_ve_forward_limit=False,
        )
        scheduler.generate_schedule()

        simulator = PipelineSimulator.from_scheduler(scheduler)
        vb30 = _find_op(simulator, rank=2, op_type="VB", microbatch_id=30, chunk_id=None)
        b30 = _find_op(simulator, rank=0, op_type="B", microbatch_id=30, chunk_id=None)
        peer_bs = [
            _find_op(simulator, rank=0, op_type="B", microbatch_id=mb, chunk_id=None)
            for mb in (28, 29, 31)
        ]

        reasons = simulator.graph.dependency_reasons[vb30.id]
        self.assertIn("llm_input_gradient_ready", reasons[b30.id])
        for peer_b in peer_bs:
            self.assertNotIn(peer_b.id, reasons)

    def test_disttrain_1f1b_layout_and_dependencies(self):
        scheduler = DistTrain1F1B(pp_size=4, num_microbatches=8)
        scheduler.generate_schedule()

        self.assertEqual(scheduler.pp_size, 6)
        self.assertEqual(scheduler.llm_pp_size, 4)
        self.assertEqual(scheduler.encoder_stage, 0)
        self.assertEqual(scheduler.generator_stage, 5)

        simulator = PipelineSimulator.from_scheduler(scheduler)
        result = simulator.simulate(_default_specs(), seed=5)
        simulator.validate_result(result)

        vf0 = _find_op(simulator, rank=0, op_type="VF", microbatch_id=0, chunk_id=None)
        f0_llm0 = _find_op(simulator, rank=1, op_type="F", microbatch_id=0, chunk_id=None)
        f0_llm_last = _find_op(simulator, rank=4, op_type="F", microbatch_id=0, chunk_id=None)
        gf0 = _find_op(simulator, rank=5, op_type="GF", microbatch_id=0, chunk_id=None)
        gb0 = _find_op(simulator, rank=5, op_type="GB", microbatch_id=0, chunk_id=None)
        b0_llm_last = _find_op(simulator, rank=4, op_type="B", microbatch_id=0, chunk_id=None)
        b0_llm0 = _find_op(simulator, rank=1, op_type="B", microbatch_id=0, chunk_id=None)
        vb0 = _find_op(simulator, rank=0, op_type="VB", microbatch_id=0, chunk_id=None)

        reasons = simulator.graph.dependency_reasons
        self.assertIn("encoder_forward_ready", reasons[f0_llm0.id][vf0.id])
        self.assertIn("llm_output_ready", reasons[gf0.id][f0_llm_last.id])
        self.assertIn("generator_backward_consumes_forward", reasons[gb0.id][gf0.id])
        self.assertIn("generator_backward_ready", reasons[b0_llm_last.id][gb0.id])
        self.assertIn("llm_input_gradient_ready", reasons[vb0.id][b0_llm0.id])

        gf1 = _find_op(simulator, rank=5, op_type="GF", microbatch_id=1, chunk_id=None)
        self.assertNotIn(gf1.id, reasons[gb0.id])

    def test_disttrain_1f1b_activation_limits(self):
        scheduler = DistTrain1F1B(pp_size=4, num_microbatches=8)
        scheduler.generate_schedule()

        forward_ops = {OpType.VEFORWARD, OpType.FORWARD, OpType.GENFORWARD}
        backward_ops = {OpType.VEBACKWARD, OpType.BACKWARD, OpType.GENBACKWARD}

        peaks = {}
        for rank, ops in scheduler.schedules.items():
            live = 0
            peak = 0
            for op in ops:
                if op.op_type in forward_ops:
                    live += 1
                    peak = max(peak, live)
                elif op.op_type in backward_ops:
                    live -= 1
            peaks[rank] = peak
            self.assertLessEqual(peak, scheduler.memory_limits[rank])
            self.assertEqual(live, 0)

        self.assertEqual(peaks[5], 1)
        self.assertEqual(peaks[4], 2)

    def test_disttrain_uses_uniform_module_durations(self):
        scheduler = DistTrain1F1B(pp_size=4, num_microbatches=8)
        scheduler.generate_schedule()

        forward_ops = {OpType.VEFORWARD, OpType.FORWARD, OpType.GENFORWARD}
        backward_ops = {OpType.VEBACKWARD, OpType.BACKWARD, OpType.GENBACKWARD}

        for ops in scheduler.schedules.values():
            for op in ops:
                if op.op_type in forward_ops:
                    self.assertEqual(op.duration, scheduler.forward_duration)
                elif op.op_type in backward_ops:
                    self.assertEqual(op.duration, scheduler.backward_duration)

        rank4_ops = [
            (op.op_type, op.microbatch_id)
            for op in scheduler.schedules[4]
            if op.op_type is not OpType.IDLE
        ]
        self.assertLess(
            rank4_ops.index((OpType.BACKWARD, 0)),
            rank4_ops.index((OpType.FORWARD, 2)),
        )

    def test_disttrain_encoder_1f1b_layout_and_dependencies(self):
        scheduler = DistTrainEncoder1F1B(pp_size=4, num_microbatches=8)
        scheduler.generate_schedule()

        self.assertEqual(scheduler.pp_size, 5)
        self.assertEqual(scheduler.llm_pp_size, 4)
        self.assertEqual(scheduler.encoder_stage, 0)
        self.assertIsNone(scheduler.generator_stage)
        self.assertFalse(scheduler.pipeline_layout["has_generator"])

        all_op_types = {op.op_type for ops in scheduler.schedules.values() for op in ops}
        self.assertNotIn(OpType.GENFORWARD, all_op_types)
        self.assertNotIn(OpType.GENBACKWARD, all_op_types)

        simulator = PipelineSimulator.from_scheduler(scheduler)
        result = simulator.simulate(_default_specs(), seed=11)
        simulator.validate_result(result)

        vf0 = _find_op(simulator, rank=0, op_type="VF", microbatch_id=0, chunk_id=None)
        f0_llm0 = _find_op(simulator, rank=1, op_type="F", microbatch_id=0, chunk_id=None)
        f0_llm_last = _find_op(simulator, rank=4, op_type="F", microbatch_id=0, chunk_id=None)
        b0_llm_last = _find_op(simulator, rank=4, op_type="B", microbatch_id=0, chunk_id=None)
        b0_llm0 = _find_op(simulator, rank=1, op_type="B", microbatch_id=0, chunk_id=None)
        vb0 = _find_op(simulator, rank=0, op_type="VB", microbatch_id=0, chunk_id=None)

        reasons = simulator.graph.dependency_reasons
        self.assertIn("encoder_forward_ready", reasons[f0_llm0.id][vf0.id])
        self.assertIn("backward_consumes_forward_activation", reasons[b0_llm_last.id][f0_llm_last.id])
        self.assertNotIn("generator_backward_ready", {
            reason
            for dep_reasons in reasons[b0_llm_last.id].values()
            for reason in dep_reasons
        })
        self.assertIn("llm_input_gradient_ready", reasons[vb0.id][b0_llm0.id])

    def test_compare_uses_shared_duration_per_rank_op_microbatch_chunk(self):
        payload = {
            "scheduler_a": "GPipe",
            "scheduler_b": "Schedule1F1B",
            "workload": {
                "pp_size": 2,
                "vpp_size": 1,
                "num_microbatches": 4,
                "ve_forward_limit": 3,
                "include_encoder": False,
                "include_generator": False,
            },
            "duration_specs": {
                "F": {"mean": 1.0, "variance": 0.1},
                "B": {"mean": 2.0, "variance": 0.1},
            },
            "seed": 17,
        }

        response = run_comparison(payload)
        result_a = response["result_a"]
        result_b = response["result_b"]

        for rank in (0, 1):
            a_op = _find_result_op(result_a, rank=rank, op_type="F", microbatch_id=0, chunk_id=None)
            b_op = _find_result_op(result_b, rank=rank, op_type="F", microbatch_id=0, chunk_id=None)
            self.assertEqual(a_op["duration"], b_op["duration"])

        rank0 = _find_result_op(result_a, rank=0, op_type="F", microbatch_id=0, chunk_id=None)
        rank1 = _find_result_op(result_a, rank=1, op_type="F", microbatch_id=0, chunk_id=None)
        self.assertNotEqual(rank0["duration"], rank1["duration"])

    def test_compare_rejects_incompatible_scheduler_shape(self):
        payload = {
            "scheduler_a": "GPipe",
            "scheduler_b": "BigMac",
            "workload": {
                "pp_size": 2,
                "vpp_size": 1,
                "num_microbatches": 4,
                "ve_forward_limit": 3,
                "include_encoder": False,
                "include_generator": False,
            },
            "duration_specs": _default_web_specs(),
            "seed": 17,
        }

        with self.assertRaises(ValueError):
            run_comparison(payload)

    def test_compare_can_allow_vpp_and_non_vpp_with_llm_duration_scale(self):
        payload = {
            "scheduler_a": "GPipe",
            "scheduler_b": "VPP1F1BSchedule",
            "workload": {
                "pp_size": 2,
                "vpp_size": 2,
                "num_microbatches": 4,
                "ve_forward_limit": 3,
                "include_encoder": False,
                "include_generator": False,
            },
            "duration_specs": _default_web_specs(),
            "seed": 17,
        }

        response = run_comparison(payload)
        self.assertTrue(response["comparison"]["workload"]["allow_cross_vpp"])
        self.assertEqual(response["result_b"]["metadata"]["vpp_size"], 2)

        non_vpp_f = _find_result_op(
            response["result_a"],
            rank=0,
            op_type="F",
            microbatch_id=0,
            chunk_id=None,
        )
        vpp_f_c0 = _find_result_op(
            response["result_b"],
            rank=0,
            op_type="F",
            microbatch_id=0,
            chunk_id=0,
        )
        vpp_f_c1 = _find_result_op(
            response["result_b"],
            rank=0,
            op_type="F",
            microbatch_id=0,
            chunk_id=1,
        )

        self.assertEqual(vpp_f_c0["duration"], non_vpp_f["duration"] / 2)
        self.assertEqual(vpp_f_c1["duration"], non_vpp_f["duration"] / 2)

    def test_compare_adjusts_disttrain_stage_budget_and_llm_duration_scale(self):
        payload = {
            "scheduler_a": "BigMac",
            "scheduler_b": "DistTrainEncoder1F1B",
            "workload": {
                "pp_size": 4,
                "vpp_size": 1,
                "num_microbatches": 8,
                "ve_forward_limit": 3,
                "include_encoder": True,
                "include_generator": False,
            },
            "duration_specs": _default_web_specs(),
            "seed": 17,
        }

        response = run_comparison(payload)
        disttrain = response["result_b"]
        self.assertEqual(disttrain["metadata"]["pp_size"], 4)
        self.assertEqual(disttrain["metadata"]["pipeline_layout"]["llm_pp_size"], 3)

        bigmac_f = _find_result_op(
            response["result_a"],
            rank=1,
            op_type="F",
            microbatch_id=0,
            chunk_id=None,
        )
        disttrain_f = _find_result_op(
            disttrain,
            rank=1,
            op_type="F",
            microbatch_id=0,
            chunk_id=None,
        )
        self.assertAlmostEqual(disttrain_f["duration"], bigmac_f["duration"] * 4 / 3)

def _find_op(simulator, *, rank, op_type, microbatch_id, chunk_id):
    for op in simulator.plan.ops_by_rank[rank]:
        if (
            op.op_type == op_type
            and op.microbatch_id == microbatch_id
            and op.chunk_id == chunk_id
        ):
            return op
    raise AssertionError(
        f"missing op rank={rank} op_type={op_type} "
        f"microbatch_id={microbatch_id} chunk_id={chunk_id}"
    )


def _find_result_op(result, *, rank, op_type, microbatch_id, chunk_id):
    for op in result["ops"]:
        if (
            op["rank"] == rank
            and op["op_type"] == op_type
            and op["microbatch_id"] == microbatch_id
            and op["chunk_id"] == chunk_id
        ):
            return op
    raise AssertionError(
        f"missing result op rank={rank} op_type={op_type} "
        f"microbatch_id={microbatch_id} chunk_id={chunk_id}"
    )


def _default_specs():
    return {
        "F": OpDurationSpec(mean=1.0),
        "B": OpDurationSpec(mean=2.0),
        "VF": OpDurationSpec(mean=0.8),
        "VB": OpDurationSpec(mean=0.9),
        "GF": OpDurationSpec(mean=0.6),
        "GB": OpDurationSpec(mean=0.7),
    }


def _default_web_specs():
    return {
        "F": {"mean": 1.0, "variance": 0.0},
        "B": {"mean": 2.0, "variance": 0.0},
        "VF": {"mean": 0.8, "variance": 0.0},
        "VB": {"mean": 0.9, "variance": 0.0},
        "GF": {"mean": 0.6, "variance": 0.0},
        "GB": {"mean": 0.7, "variance": 0.0},
    }


if __name__ == "__main__":
    unittest.main()