Files
xc-llm-ascend/tests/e2e/singlecard/test_auto_fit_max_mode_len.py
Li Wang 63adbedb7a [Worker] Implement update max_model_len interface for NPUWorker (#6193)
### What this PR does / why we need it?
This patch purpose to add the `update_max_model_len` interface.

- vLLM version: v0.14.0
- vLLM main:
d68209402d

---------

Signed-off-by: wangli <wangli858794774@gmail.com>
2026-01-26 09:03:33 +08:00

101 lines
3.7 KiB
Python

#
# Copyright (c) 2025 Huawei Technologies Co., Ltd. All Rights Reserved.
# This file is a part of the vllm-ascend project.
# Adapted from vllm/tests/entrypoints/llm/test_guided_generate.py
# Copyright 2023 The vLLM team.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
import torch
from vllm.config import ModelConfig, VllmConfig
from vllm.v1.core.kv_cache_utils import get_kv_cache_configs
from vllm.v1.kv_cache_interface import FullAttentionSpec
def new_kv_cache_spec(
block_size=16,
num_kv_heads=2,
head_size=64,
dtype=torch.float32,
page_size_padded=None,
sliding_window=None,
attention_chunk_size=None,
):
return FullAttentionSpec(
block_size=block_size,
num_kv_heads=num_kv_heads,
head_size=head_size,
dtype=dtype,
page_size_padded=page_size_padded,
sliding_window=sliding_window,
attention_chunk_size=attention_chunk_size,
)
def test_auto_fit_max_model_len():
"""Test that max_model_len=-1 auto-fits to available NPU memory."""
# Create config with original_max_model_len=-1 to trigger auto-fit
model_config = ModelConfig(max_model_len=1024)
# Simulate the user passing -1 by setting original_max_model_len
model_config.original_max_model_len = -1
vllm_config = VllmConfig(model_config=model_config)
# block_size * 2 * head_size * num_kv_heads * dtype_size
mem_per_block_per_layer = 16 * 2 * 64 * 4 * 2 # 16KB per block per layer
kv_cache_specs = {
"layer_1": new_kv_cache_spec(),
"layer_2": new_kv_cache_spec(),
}
# With enough memory, max_model_len stays at the derived max
large_available_memory = mem_per_block_per_layer * 2 * 1024 # plenty of memory
_kv_cache_configs = get_kv_cache_configs(
vllm_config, [kv_cache_specs], [large_available_memory]
)
assert vllm_config.model_config.max_model_len == 1024
# Reset for next test
model_config = ModelConfig(max_model_len=1024)
model_config.original_max_model_len = -1
vllm_config = VllmConfig(model_config=model_config)
# With limited memory, max_model_len should be reduced
# Need memory for at least max_model_len tokens
# 32 blocks worth of memory for 2 layers = can fit 32*16=512 tokens
limited_memory = mem_per_block_per_layer * 2 * 32
_kv_cache_configs = get_kv_cache_configs(
vllm_config, [kv_cache_specs], [limited_memory]
)
# Should be reduced to fit in memory
assert vllm_config.model_config.max_model_len < 1024
assert vllm_config.model_config.max_model_len > 0
def test_auto_fit_max_model_len_not_triggered():
"""Test that auto-fit is not triggered when original_max_model_len is not -1."""
model_config = ModelConfig(max_model_len=16)
# original_max_model_len should be None by default, not -1
vllm_config = VllmConfig(model_config=model_config)
mem_per_block_per_layer = 16 * 2 * 64 * 4 * 2
kv_cache_specs = {
"layer_1": new_kv_cache_spec(),
"layer_2": new_kv_cache_spec(),
}
# This should work normally without auto-fit
_kv_cache_configs = get_kv_cache_configs(
vllm_config, [kv_cache_specs], [mem_per_block_per_layer * 2 * 32]
)
assert vllm_config.model_config.max_model_len == 16