test_utils.py

# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project

import torch

from vllm.v1.worker.utils import bind_kv_cache


def test_bind_kv_cache():
    from vllm.attention.layer import Attention

    ctx = {
        "layers.0.self_attn": Attention(32, 128, 0.1),
        "layers.1.self_attn": Attention(32, 128, 0.1),
        "layers.2.self_attn": Attention(32, 128, 0.1),
        "layers.3.self_attn": Attention(32, 128, 0.1),
    }
    kv_cache = {
        "layers.0.self_attn": torch.zeros((1,)),
        "layers.1.self_attn": torch.zeros((1,)),
        "layers.2.self_attn": torch.zeros((1,)),
        "layers.3.self_attn": torch.zeros((1,)),
    }
    runner_kv_caches: list[torch.Tensor] = []
    bind_kv_cache(kv_cache, ctx, runner_kv_caches)
    assert ctx["layers.0.self_attn"].kv_cache[0] is kv_cache["layers.0.self_attn"]
    assert ctx["layers.1.self_attn"].kv_cache[0] is kv_cache["layers.1.self_attn"]
    assert ctx["layers.2.self_attn"].kv_cache[0] is kv_cache["layers.2.self_attn"]
    assert ctx["layers.3.self_attn"].kv_cache[0] is kv_cache["layers.3.self_attn"]

    assert runner_kv_caches[0] is kv_cache["layers.0.self_attn"]
    assert runner_kv_caches[1] is kv_cache["layers.1.self_attn"]
    assert runner_kv_caches[2] is kv_cache["layers.2.self_attn"]
    assert runner_kv_caches[3] is kv_cache["layers.3.self_attn"]


def test_bind_kv_cache_non_attention():
    from vllm.attention.layer import Attention

    # example from Jamba PP=2
    ctx = {
        "model.layers.20.attn": Attention(32, 128, 0.1),
        "model.layers.28.attn": Attention(32, 128, 0.1),
    }
    kv_cache = {
        "model.layers.20.attn": torch.zeros((1,)),
        "model.layers.28.attn": torch.zeros((1,)),
    }

    runner_kv_caches: list[torch.Tensor] = []
    bind_kv_cache(kv_cache, ctx, runner_kv_caches)

    assert ctx["model.layers.20.attn"].kv_cache[0] is kv_cache["model.layers.20.attn"]
    assert ctx["model.layers.28.attn"].kv_cache[0] is kv_cache["model.layers.28.attn"]

    assert runner_kv_caches[0] is kv_cache["model.layers.20.attn"]
    assert runner_kv_caches[1] is kv_cache["model.layers.28.attn"]