Files
xc-llm-ascend/tests/ut/core/test_schedule_config.py
Csrayz 80524f5711 [CORE] concurrent partial prefills (#2372)
# What this PR does / why we need it?

When processing a mix of large and small requests, the TTFT of responses
is significantly reduc\ed. Please refer to
https://github.com/vllm-project/vllm/pull/10235, which achieves the same
effect by simply limiting the number of prompt fills for long requests.
This solution can be applied to both AscendScheduler (V0) and vLLM
Scheduler (V1). Tests show that TTFT can be significantly improved when
handling such mixed requests. However, This capability is currently
missing when Ascend Scheduler is enabled.

This benchmark used the Qwen3-8B model, with a context length of 128K,
running on a single card.

Regarding dataset selection, the sharegpt_clean dataset is used, with
its content concatenated and cropped. Small requests with token=50 and
medium requests with token=10240 were constructed (there were also large
requests with token=102400, but these were ignored because when using
the Prefill First scheduling strategy, max_num_batched_tokens will not
be set to such a large value). When loading vLLM, set
max_num_batched_tokens=22000. This length can accommodate two
medium-sized requests and some short requests, reflecting an extreme
scenario where the budget is almost entirely occupied by longer
requests.

Next, we mix 990 small requests and 100 medium requests into one type of
load scenario (hereinafter referred to as 10%), and similarly generate
load scenarios with 5% medium requests and 1% load scenarios.

Performance tests were conducted separately for enabling vLLMScheduler,
AscendScheduler, and AscendScheduler (long prompt concurrency set to 1).

- vLLM version: v0.10.2
- vLLM main:
1dfea5f4a9

---------

Signed-off-by: Csrayz <jover@cmbchina.com>
2025-09-24 17:12:55 +08:00

149 lines
6.1 KiB
Python

#
# Copyright (c) 2025 Huawei Technologies Co., Ltd. All Rights Reserved.
#
# 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.
from vllm.config import SchedulerConfig
from tests.ut.base import TestBase
from vllm_ascend.core.schedule_config import AscendSchedulerConfig
class TestAscendSchedulerConfig(TestBase):
def setUp(self):
self.basic_scheduler_config = SchedulerConfig(
max_num_batched_tokens=8192,
max_model_len=8192,
is_multimodal_model=False,
send_delta_data=False,
)
def test_initialize_from_config_with_default(self):
# No additional config given, check the default value here.
ascend_config = AscendSchedulerConfig.initialize_from_config(
self.basic_scheduler_config, {})
self.assertEqual(ascend_config.enable_chunked_prefill, False)
self.assertEqual(ascend_config.policy, "fcfs")
self.assertEqual(ascend_config.scheduler_cls,
"vllm_ascend.core.scheduler.AscendScheduler")
self.assertEqual(ascend_config.max_num_encoder_input_tokens, 8192)
self.assertEqual(ascend_config.encoder_cache_size, 8192)
def test_initialize_from_config_with_override(self):
# test override
ascend_config = AscendSchedulerConfig.initialize_from_config(
self.basic_scheduler_config,
AscendSchedulerConfig(
enable_chunked_prefill=False,
policy="fcfs",
scheduler_cls="vllm_ascend.core.scheduler.AscendScheduler",
max_num_batched_tokens=2048,
max_model_len=2048,
max_long_partial_prefills=1,
long_prefill_token_threshold=512,
),
)
self.assertEqual(ascend_config.enable_chunked_prefill, False)
self.assertEqual(ascend_config.policy, "fcfs")
self.assertEqual(ascend_config.scheduler_cls,
"vllm_ascend.core.scheduler.AscendScheduler")
self.assertEqual(ascend_config.max_num_batched_tokens, 2048)
self.assertEqual(ascend_config.encoder_cache_size, 2048)
self.assertEqual(ascend_config.max_long_partial_prefills, 1)
self.assertEqual(ascend_config.long_prefill_token_threshold, 512)
def test_not_implemented_policy(self):
with self.assertRaises(NotImplementedError) as context:
AscendSchedulerConfig.initialize_from_config(
self.basic_scheduler_config,
AscendSchedulerConfig(
policy="custom_policy",
max_num_batched_tokens=2048,
max_model_len=2048,
),
)
self.assertIn(
"currently AscendScheduler only supports fcfs policy",
str(context.exception),
)
def test_not_implemented_send_delta_data(self):
with self.assertRaises(NotImplementedError) as context:
AscendSchedulerConfig.initialize_from_config(
self.basic_scheduler_config,
AscendSchedulerConfig(
send_delta_data=True,
max_num_batched_tokens=2048,
max_model_len=2048,
),
)
self.assertIn(
"currently AscendScheduler doesn't support send_delta_data",
str(context.exception),
)
def test_no_override(self):
ascend_config = AscendSchedulerConfig.initialize_from_config(
self.basic_scheduler_config, {})
self.assertEqual(ascend_config.max_num_encoder_input_tokens, 8192)
self.assertEqual(ascend_config.encoder_cache_size, 8192)
def test_valid_config_with_multimodal(self):
config = AscendSchedulerConfig.initialize_from_config(
SchedulerConfig(is_multimodal_model=True), {})
self.assertTrue(config.is_multimodal_model)
def test_valid_config_with_chunked_prefill(self):
ascend_config = AscendSchedulerConfig.initialize_from_config(
self.basic_scheduler_config,
AscendSchedulerConfig(
enable_chunked_prefill=True,
max_num_batched_tokens=2048,
max_model_len=4096,
),
)
self.assertEqual(ascend_config.max_num_batched_tokens, 2048)
self.assertEqual(ascend_config.max_model_len, 4096)
self.assertTrue(ascend_config.enable_chunked_prefill)
def test_invalid_config_without_chunked_prefill(self):
with self.assertRaises(ValueError) as context:
AscendSchedulerConfig.initialize_from_config(
self.basic_scheduler_config,
AscendSchedulerConfig(
enable_chunked_prefill=False,
max_num_batched_tokens=2048,
max_model_len=4096,
),
)
self.assertIn(
"Ascend scheduler is enabled without chunked prefill feature",
str(context.exception),
)
self.assertIn("max_num_batched_tokens (2048)", str(context.exception))
self.assertIn("max_model_len (4096)", str(context.exception))
def test_initialize_from_config_with_pd_transfer(self):
ascend_config = AscendSchedulerConfig.initialize_from_config(
self.basic_scheduler_config,
AscendSchedulerConfig(
enable_pd_transfer=True,
decode_max_num_seqs=48,
max_num_batched_tokens=4096,
max_model_len=4096,
),
)
self.assertEqual(ascend_config.enable_pd_transfer, True)
self.assertEqual(ascend_config.decode_max_num_seqs, 48)