ApsarasX 0fc9b56d40 [Perf] Improve MLA multistream performance (#1353)
### What this PR does / why we need it?
> Need to merge after PR #1322

According to benchmark results, this PR brings approximately 1%
performance gain.

#### Before Improvement
Profiling
<img width="1147" alt="截屏2025-06-22 14 54 47"
src="https://github.com/user-attachments/assets/4a4dc7f1-5b76-45d5-864d-dd7f8faf993c"
/>

Evaluation
```
# server launch command
python -m vllm.entrypoints.openai.api_server --model=/DeepSeek-R1-W8A8 \
    --quantization ascend \
    --served-model-name auto \
    --trust-remote-code \
    --distributed-executor-backend=mp \
    --port 8006 \
    -tp=16 \
    --max-num-seqs 24 \
    --max-model-len 32768 \
    --max-num-batched-tokens 8192 \
    --block-size 128 \
    --no-enable-prefix-caching \
    --additional-config '{"torchair_graph_config":{"enable_multistream_mla": true,"enabled":true,"use_cached_graph":true,"graph_batch_sizes":[24]},"ascend_scheduler_config":{"enabled":true},"expert_tensor_parallel_size":16}' \
    --gpu-memory-utilization 0.96

# client benchmark command
python /root/vllm/benchmarks/benchmark_serving.py --backend vllm --dataset-name random \
        --random-input-len 4096 \
        --random-output-len 1536 \
        --num-prompts 200 \
        --ignore-eos \
        --model auto \
        --tokenizer /DeepSeek-R1-W8A8 \
        --port 8006 \
        --request-rate 1 \
        --max-concurrency 24 \
        --save-result \
        --skip-initial-test \
        --metric-percentiles "50,90,99"
```

```
============ Serving Benchmark Result ============
Successful requests:                     200       
Benchmark duration (s):                  958.59    
Total input tokens:                      819200    
Total generated tokens:                  307200    
Request throughput (req/s):              0.2086    
Output token throughput (tok/s):         320.47    
Total Token throughput (tok/s):          1175.05   
---------------Time to First Token----------------
Mean TTFT (ms):                          942.70    
Median TTFT (ms):                        713.87    
P50 TTFT (ms):                           713.87    
P90 TTFT (ms):                           1363.88   
P99 TTFT (ms):                           2008.73   
-----Time per Output Token (excl. 1st token)------
Mean TPOT (ms):                          68.96     
Median TPOT (ms):                        69.49     
P50 TPOT (ms):                           69.49     
P90 TPOT (ms):                           70.42     
P99 TPOT (ms):                           70.72     
---------------Inter-token Latency----------------
Mean ITL (ms):                           68.96     
Median ITL (ms):                         59.88     
P50 ITL (ms):                            59.88     
P90 ITL (ms):                            61.59     
P99 ITL (ms):                            68.82     
==================================================
```

#### After Improvement
Profiling
<img width="1200" alt="截屏2025-06-22 14 55 42"
src="https://github.com/user-attachments/assets/e3eb9dec-0ff0-4e5f-ab94-93c65003e51f"
/>

Evaluation
```
============ Serving Benchmark Result ============
Successful requests:                     200       
Benchmark duration (s):                  948.08    
Total input tokens:                      819200    
Total generated tokens:                  307200    
Request throughput (req/s):              0.2110    
Output token throughput (tok/s):         324.02    
Total Token throughput (tok/s):          1188.08   
---------------Time to First Token----------------
Mean TTFT (ms):                          1019.25   
Median TTFT (ms):                        714.63    
P50 TTFT (ms):                           714.63    
P90 TTFT (ms):                           1367.31   
P99 TTFT (ms):                           2661.52   
-----Time per Output Token (excl. 1st token)------
Mean TPOT (ms):                          68.14     
Median TPOT (ms):                        68.68     
P50 TPOT (ms):                           68.68     
P90 TPOT (ms):                           69.33     
P99 TPOT (ms):                           70.30     
---------------Inter-token Latency----------------
Mean ITL (ms):                           68.14     
Median ITL (ms):                         59.04     
P50 ITL (ms):                            59.04     
P90 ITL (ms):                            60.93     
P99 ITL (ms):                            66.89     
==================================================
```
### Does this PR introduce _any_ user-facing change?
No

### How was this patch tested?




- vLLM version: v0.9.2
- vLLM main:
65393ee064

Signed-off-by: ApsarasX <apsarax@outlook.com>
2025-07-11 08:51:17 +08:00
2025-07-10 14:26:59 +08:00
2025-06-27 09:14:43 +08:00
2025-02-05 10:53:12 +08:00
2025-01-29 02:44:13 -08:00
2025-06-25 19:28:26 +08:00
2025-06-25 19:28:26 +08:00
2025-06-27 09:14:43 +08:00

vllm-ascend

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Overview

vLLM Ascend (vllm-ascend) is a community maintained hardware plugin for running vLLM seamlessly on the Ascend NPU.

It is the recommended approach for supporting the Ascend backend within the vLLM community. It adheres to the principles outlined in the [RFC]: Hardware pluggable, providing a hardware-pluggable interface that decouples the integration of the Ascend NPU with vLLM.

By using vLLM Ascend plugin, popular open-source models, including Transformer-like, Mixture-of-Expert, Embedding, Multi-modal LLMs can run seamlessly on the Ascend NPU.

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