fix(aisimulate): pass trace workloads straight to the AIC generator

Cargo.toml

@@ -60,7 +60,7 @@ keywords = ["llm", "genai", "inference", "nvidia", "distributed"]
 [workspace.dependencies]
 dynamo-custom-policy-builtin = { path = "lib/router-plugins/builtin", version = "1.7.0" }
 # Published separately by https://github.com/ai-dynamo/aisimulate.
-aisimulate-core = { version = "=0.13.0-dev.202610280000000086" }
+aisimulate-core = { version = "=0.13.0-dev.202610290000000087" }
 
 # Local crates
 dynamo-runtime = { path = "lib/runtime", version = "1.7.0" }

benchmarks/pyproject.toml

@@ -39,7 +39,7 @@ classifiers = [
 ]
 
 dependencies = [
-    "aisimulate==0.13.0.dev202610280000000086 ; python_version >= '3.11' and python_version < '3.14'",
+    "aisimulate==0.13.0.dev202610290000000087 ; python_version >= '3.11' and python_version < '3.14'",
     "aiperf==0.13.0",
     "matplotlib",
     "networkx",

components/src/dynamo/aisimulate/output/dgd/renderers/aic/renderer.py

@@ -6,26 +6,15 @@
 from __future__ import annotations
 
 import importlib
-from collections.abc import Mapping
 from typing import Any
 
-import yaml
-
 from dynamo.aisimulate.output.dgd.renderers.base import (
     CandidateLike,
     CandidateMaterializationError,
     DGDGenerationOptions,
     patch_dgd_manifest,
 )
 
-# AIC requires a workload ISL/OSL. With the evaluated engine limits preserved,
-# the only engine field it still derives from them is TensorRT-LLM's
-# disaggregated KV-transfer buffer. A trace has no single request length, so
-# AIC gets placeholder lengths and the buffer size derived from them is dropped,
-# leaving TensorRT-LLM's default, which covers max_seq_len.
-_TRACE_PLACEHOLDER_LENGTH = 1
-_TRANSFER_BUFFER_ARG = "--trtllm.cache_transceiver_config.max_tokens_in_buffer"
-
 
 def _load_generator_api() -> tuple[Any, Any]:
     """Load the Sweeper-result bridge shipped by AISimulate."""
@@ -56,71 +45,6 @@ def _generator_overrides(
     }
 
 
-def _workload_field(workload: Any, name: str) -> Any:
-    if isinstance(workload, Mapping):
-        return workload.get(name)
-    return getattr(workload, name, None)
-
-
-def _is_trace_workload(workload: Any) -> bool:
-    return bool(
-        _workload_field(workload, "trace_paths")
-        or _workload_field(workload, "trace_path")
-    ) and (
-        _workload_field(workload, "isl") is None
-        or _workload_field(workload, "osl") is None
-    )
-
-
-def _with_placeholder_lengths(workload: Any) -> dict[str, Any]:
-    """Copy a trace workload with the placeholder lengths AIC requires.
-
-    The keys are overwritten rather than supplied as ``SlaConfig`` overrides
-    because AIC prefers a workload's present ``None`` values over overrides.
-    """
-    if isinstance(workload, Mapping):
-        payload = dict(workload)
-    elif hasattr(workload, "model_dump"):
-        payload = workload.model_dump(mode="json")
-    else:
-        payload = dict(vars(workload))
-    payload["isl"] = payload["osl"] = _TRACE_PLACEHOLDER_LENGTH
-    return payload
-
-
-def _drop_transfer_buffer_size(rendered: str) -> str:
-    """Remove the KV-transfer buffer size AIC derived from placeholder lengths.
-
-    Only the size goes; the transceiver backend stays, since TensorRT-LLM
-    disables KV transfer without one.
-    """
-    from dynamo.profiler.utils.config import (
-        break_arguments,
-        get_main_container_dict,
-        remove_all_argument_occurrences,
-    )
-
-    documents = [document for document in yaml.safe_load_all(rendered) if document]
-    changed = False
-    for document in documents:
-        if not isinstance(document, dict):
-            continue
-        for component in (document.get("spec") or {}).get("components") or []:
-            container = (
-                get_main_container_dict(component)
-                if isinstance(component, dict)
-                else None
-            )
-            if container is None:
-                continue
-            args = break_arguments(container.get("args"))
-            kept = remove_all_argument_occurrences(args, _TRANSFER_BUFFER_ARG)
-            if kept != args:
-                container["args"] = kept
-                changed = True
-    return yaml.safe_dump_all(documents, sort_keys=False) if changed else rendered
-
-
 def render(
     candidate: CandidateLike,
     workload: Any,
@@ -130,10 +54,9 @@ def render(
 ) -> str:
     """Lower one Sweeper result through AIC and Dynamo's v1 templates."""
     from_sweeper_candidate, generate_from_request = _load_generator_api()
-    trace = _is_trace_workload(workload)
     request = from_sweeper_candidate(
         candidate,
-        workload=_with_placeholder_lengths(workload) if trace else workload,
+        workload=workload,
         deployment_target="dynamo-python",
         generator_overrides=_generator_overrides(options, dgd_name=dgd_name),
     )
@@ -143,8 +66,6 @@ def render(
         raise CandidateMaterializationError(
             "AIC generator did not return k8s_deploy.yaml"
         )
-    if trace:
-        rendered = _drop_transfer_buffer_size(rendered)
     return patch_dgd_manifest(
         rendered,
         candidate,

components/src/dynamo/aisimulate/tests/dgd/test_renderers.py

@@ -263,50 +263,6 @@ def test_installed_aic_renders_real_disaggregated_candidate(monkeypatch) -> None
     assert workers["decode"]["replicas"] == 1
 
 
-@pytest.mark.parametrize(
-    "make_workload", [dict, lambda **fields: SimpleNamespace(**fields)]
-)
-def test_aic_renderer_gives_trace_workloads_placeholder_lengths(
-    monkeypatch, make_workload
-) -> None:
-    captured = []
-
-    def fake_from_sweeper_candidate(candidate, *, workload, **_kwargs):
-        captured.append(workload)
-        return "request"
-
-    monkeypatch.setattr(
-        aic_renderer,
-        "_load_generator_api",
-        lambda: (
-            fake_from_sweeper_candidate,
-            lambda _request: {"k8s_deploy.yaml": "kind: DynamoGraphDeployment\n"},
-        ),
-    )
-    monkeypatch.setattr(
-        aic_renderer, "patch_dgd_manifest", lambda rendered, *_args, **_kwargs: rendered
-    )
-    fields = {
-        "trace_path": "/traces/window.jsonl",
-        "trace_paths": ["/traces/window.jsonl"],
-        "trace_format": "dynamo",
-        "isl": None,
-        "osl": None,
-    }
-    workload = make_workload(**fields)
-
-    render_dgd(_candidate(), workload, _options(), dgd_name="sweeper-dgd")
-
-    assert captured == [{**fields, "isl": 1, "osl": 1}]
-    assert _workload_lengths(workload) == (None, None)
-
-
-def _workload_lengths(workload):
-    if isinstance(workload, dict):
-        return workload["isl"], workload["osl"]
-    return workload.isl, workload.osl
-
-
 @dataclass(frozen=True)
 class _SweeperCandidate:
     config: dict
@@ -362,6 +318,20 @@ def _transfer_buffer_args(rendered: str) -> dict[str, dict[str, str]]:
     return flags
 
 
+def _without_transfer_buffer_size(rendered: str) -> dict:
+    buffer_arg = "--trtllm.cache_transceiver_config.max_tokens_in_buffer"
+    dgd = yaml.safe_load(rendered)
+    for component in dgd["spec"]["components"]:
+        for container in (
+            component.get("podTemplate", {}).get("spec", {}).get("containers", [])
+        ):
+            args = container.get("args") or []
+            if buffer_arg in args:
+                start = args.index(buffer_arg)
+                del args[start : start + 2]
+    return dgd
+
+
 @pytest.mark.parametrize(
     ("backend", "backend_version", "image"),
     [
@@ -408,11 +378,9 @@ def render(workload) -> str:
     )
     synthetic = render({"isl": 4000, "osl": 1000})
 
-    # Apart from TensorRT-LLM's transfer buffer size, nothing may depend on
-    # the placeholder lengths a trace workload gives AIC.
-    assert yaml.safe_load(traced) == yaml.safe_load(
-        aic_renderer._drop_transfer_buffer_size(synthetic)
-    )
+    # AIC derives only TensorRT-LLM's transfer buffer size from request
+    # lengths, so a trace DGD is the synthetic one without that size.
+    assert yaml.safe_load(traced) == _without_transfer_buffer_size(synthetic)
     if backend == "trtllm":
         # The trace keeps the transceiver backend; TensorRT-LLM sizes the buffer.
         assert _transfer_buffer_args(traced) == {
@@ -425,63 +393,6 @@ def render(workload) -> str:
         )
 
 
-def test_dropping_transfer_buffer_size_keeps_other_arguments() -> None:
-    buffer_arg = "--trtllm.cache_transceiver_config.max_tokens_in_buffer"
-
-    def component(component_type, args):
-        return {
-            "type": component_type,
-            "podTemplate": {"spec": {"containers": [{"name": "main", "args": args}]}},
-        }
-
-    rendered = yaml.safe_dump(
-        {
-            "kind": "DynamoGraphDeployment",
-            "spec": {
-                "components": [
-                    {"name": "Frontend", "type": "frontend"},
-                    component(
-                        "prefill",
-                        [
-                            "--trtllm.cache_transceiver_config.backend",
-                            "DEFAULT",
-                            buffer_arg,
-                            "6528",
-                            "--max-num-tokens",
-                            "4096",
-                        ],
-                    ),
-                    component(
-                        "decode", [f"{buffer_arg}=6528", "--max-batch-size", "64"]
-                    ),
-                ]
-            },
-        },
-        sort_keys=False,
-    )
-    unrelated = yaml.safe_dump(
-        {"spec": {"components": [component("worker", ["--block-size", "64"])]}}
-    )
-
-    dgd = yaml.safe_load(aic_renderer._drop_transfer_buffer_size(rendered))
-
-    args = {
-        component["type"]: component["podTemplate"]["spec"]["containers"][0]["args"]
-        for component in dgd["spec"]["components"]
-        if "podTemplate" in component
-    }
-    assert args == {
-        "prefill": [
-            "--trtllm.cache_transceiver_config.backend",
-            "DEFAULT",
-            "--max-num-tokens",
-            "4096",
-        ],
-        "decode": ["--max-batch-size", "64"],
-    }
-    assert aic_renderer._drop_transfer_buffer_size(unrelated) is unrelated
-
-
 def test_materialize_direct_uses_config_modifiers(monkeypatch) -> None:
     pytest.importorskip("aisimulate_core")
     captured = {}

container/deps/requirements.aisimulate.txt

@@ -3,4 +3,4 @@
 
 # Published AISimulate wheel staged into planner and framework runtime wheelhouses.
 # Keep in sync with the aisimulate-core pins in Cargo.toml and lib/bindings/python/Cargo.toml.
-aisimulate==0.13.0.dev202610280000000086
+aisimulate==0.13.0.dev202610290000000087

docs/fern/pages/cli/operations/simulation-with-dynosim/simulation-model.md

@@ -86,7 +86,7 @@ kv_transfer:
   timing_mode: destination_missing
 ```
 
-The offline simulation uses a per-request line-rate model:
+The offline simulation prices each transfer with a line-rate model:
 
 ```text
 transfer time = transferred KV bytes / kv_transfer_bandwidth
@@ -95,7 +95,12 @@ transferred KV bytes = charged tokens * kv_bytes_per_token
 
 `timing_mode: full_prompt` charges the full logical prompt. `destination_missing` charges only the
 prompt footprint absent from the destination and can produce zero delay on a full destination hit.
-Concurrent requests do not contend for a shared link.
+
+That time applies to a transfer alone on its links. In offline prediction, each prefill rank sends
+over one link and each decode rank receives over one link, both at the configured bandwidth.
+Transfers in flight at the same time share these links max-min fairly, so concurrent handoffs from
+one prefill rank, or into one decode rank, take longer than a lone transfer. Live Mocker workers do
+not share links: each transfer waits its own fixed delay.
 
 Set `bytes_per_token: auto` to derive the value from model metadata and parallelism, or provide a
 positive integer. Set a positive `bandwidth_gb_per_second` to apply the transfer delay. TensorRT-LLM

docs/fern/pages/reference/components/planner-configuration.mdx

@@ -185,7 +185,7 @@ build, or mount a local copy before starting Planner. Use the
 generic AISimulate wheel; measurements do not belong inside the wheel. Use matching
 AISimulate Python and Rust releases that support execution profiles through the
 common forward-pass query API. This integration pins Python
-`0.13.0.dev202610280000000086` and Rust `0.13.0-dev.202610280000000086`,
+`0.13.0.dev202610290000000087` and Rust `0.13.0-dev.202610290000000087`,
 which include that support. Use version-2 execution profiles; version 1 retains
 its legacy direct-phase queries and must be explicitly migrated and repinned.
 

lib/bindings/python/Cargo.toml

@@ -61,7 +61,7 @@ request-trace-s3 = ["dynamo-llm/request-trace-s3"]
 # former AIC crate surface. The `python` feature is required for
 # AicEngineBuilder; this extension supplies the interpreter, so the dependency
 # must not enable `extension-module`.
-aisimulate-core = { version = "=0.13.0-dev.202610280000000086", optional = true, features = ["python"] }
+aisimulate-core = { version = "=0.13.0-dev.202610290000000087", optional = true, features = ["python"] }
 dynamo-runtime = { path = "../../runtime" }
 dynamo-mocker = { path = "../../mocker" }
 dynamo-parsers = { version = "=10.2.2" }

pyproject.toml

@@ -14,7 +14,7 @@ license-files = ["LICENSE"]
 requires-python = ">=3.11"
 dependencies = [
     "ai-dynamo-runtime==1.7.0",
-    "aisimulate==0.13.0.dev202610280000000086 ; python_version >= '3.11' and python_version < '3.14'",
+    "aisimulate==0.13.0.dev202610290000000087 ; python_version >= '3.11' and python_version < '3.14'",
     "aiohttp>=3.14.3,<4.0",
     # Set the CA bundle floor for transitive HTTP clients outside containers too.
     "certifi>=2026.10.23",