### What this PR does / why we need it?
related to https://github.com/vllm-project/vllm-ascend/issues/4267
### Does this PR introduce _any_ user-facing change?
support w8a16 quantization now
### How was this patch tested?
- vLLM version: v0.12.0
- vLLM main:
ad32e3e19c
### Test
tested using [aisbench](https://gitee.com/aisbench/benchmark/) with tp2
#### Precision
| ceval | mmlu | gsm8k
-- | -- | -- | --
bf16 | 90.46 | 89.17 | 96.21
w8a16 | 89.51 | 89.29 | 95.98
#### Performance
| input_len | output_len | concurrency | TTFT (ms) | TPOT (ms) | TPS
(Total) (tokens/s)
-- | -- | -- | -- | -- | -- | --
bf16 | 2048 | 2048 | 10 | 1911.7136 | 77.988 | 253.9866
w8a16 | 2048 | 2048 | 10 | 2128.6334 | 67.1633 | 293.9117
bf16 | 3500 | 1024 | 10 | 3076.2509 | 84.3525 | 506.949
w8a16 | 3500 | 1024 | 10 | 2685.2031 | 73.015 | 585.4717
---------
Signed-off-by: yyt <yangyit139@gmail.com>
Signed-off-by: TmacAaron <yangyit139@gmail.com>
Co-authored-by: realliujiaxu <realliujiaxu@163.com>