A high-throughput and memory-efficient inference and serving engine for LLMs
Mirrored from https://github.com/tduncan-lum/Nvidia-Optimization-Stack---VLLM.git
Synced Nov 15, 22:15 UTC
[Bugfix][Quantization] Fix FP8 + EP (#13784)
Signed-off-by: Tyler Michael Smith <tyler@neuralmagic.com>
Tyler Michael Smith committed
Feb 24, 2025 at 21:54 UTC
1e15aaef562de78b4684e88ed56bc18b3860e724
6 files changed
+22
-22
vllm/model_executor/layers/fused_moe/layer.py
+15
-15
@@ -260,7 +260,7 @@ class FusedMoE(torch.nn.Module):
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def __init__(
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self,
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- num_experts: int,
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+ num_experts: int, # Global number of experts
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top_k: int,
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hidden_size: int,
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intermediate_size: int,
@@ -291,7 +291,8 @@ class FusedMoE(torch.nn.Module):
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else:
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self.ep_size = 1
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self.top_k = top_k
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- self.num_experts = num_experts # Global number of experts
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+ self.global_num_experts = num_experts
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+ self.local_num_experts = self.global_num_experts // self.ep_size
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assert intermediate_size % self.tp_size == 0
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self.intermediate_size_per_partition = intermediate_size // self.tp_size
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self.reduce_results = reduce_results
@@ -308,27 +309,29 @@ class FusedMoE(torch.nn.Module):
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if self.ep_size > 1:
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# Create a tensor of size num_experts filled with -1
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- self.expert_map = torch.full((self.num_experts, ),
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+ self.expert_map = torch.full((self.global_num_experts, ),
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-1,
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dtype=torch.int32)
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# Create a expert map for the local experts
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- local_num_experts = num_experts // self.ep_size
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ep_rank = get_tensor_model_parallel_rank()
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if ep_rank < (self.ep_size - 1):
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# Each non-last rank gets local_num_experts experts.
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- self.expert_map[ep_rank * local_num_experts:
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- (ep_rank + 1) * local_num_experts] = \
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- torch.arange(0, local_num_experts, dtype=torch.int32)
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+ self.expert_map[ep_rank * self.local_num_experts:
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+ (ep_rank + 1) * self.local_num_experts] = \
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+ torch.arange(0, self.local_num_experts, dtype=torch.int32)
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else:
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# All remaining experts are assigned to the last rank.
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- local_num_experts = num_experts - ep_rank * local_num_experts
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- self.expert_map[-local_num_experts:] = \
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- torch.arange(0, local_num_experts, dtype=torch.int32)
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+ self.local_num_experts = (self.global_num_experts -
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+ ep_rank * self.local_num_experts)
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+ self.expert_map[-self.local_num_experts:] = \
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+ torch.arange(0, self.local_num_experts, dtype=torch.int32)
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if self.scoring_func != "softmax" and not self.use_grouped_topk:
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raise ValueError("Only softmax scoring function is supported for "
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"non-grouped topk.")
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+ # Note: get_quant_method will look at the layer's local_num_experts
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+ # for heuristic purposes, so it must be initialized first.
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if quant_config is None:
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self.quant_method: Optional[QuantizeMethodBase] = (
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UnquantizedFusedMoEMethod())
@@ -336,11 +339,8 @@ class FusedMoE(torch.nn.Module):
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self.quant_method = quant_config.get_quant_method(self, prefix)
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assert self.quant_method is not None
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- local_num_experts = torch.sum(self.expert_map != -1) \
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- if self.expert_map is not None else num_experts
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-
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moe_quant_params = {
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- "num_experts": local_num_experts,
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+ "num_experts": self.local_num_experts,
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"hidden_size": hidden_size,
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"intermediate_size_per_partition":
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self.intermediate_size_per_partition,
@@ -647,7 +647,7 @@ class FusedMoE(torch.nn.Module):
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top_k=self.top_k,
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renormalize=self.renormalize,
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use_grouped_topk=self.use_grouped_topk,
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- global_num_experts=self.num_experts,
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+ global_num_experts=self.global_num_experts,
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expert_map=self.expert_map,
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topk_group=self.topk_group,
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num_expert_group=self.num_expert_group,
vllm/model_executor/layers/quantization/awq_marlin.py
+1
-1
@@ -136,7 +136,7 @@ class AWQMarlinConfig(QuantizationConfig):
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self.full_config).get_quant_method(layer, prefix)
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return AWQMarlinLinearMethod(self)
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elif isinstance(layer, FusedMoE):
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- if layer.num_experts > 32:
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+ if layer.local_num_experts > 32:
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# For MoEs with many experts the moe_wna16 kernel is faster
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return MoeWNA16Config.from_config(
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self.full_config).get_quant_method(layer, prefix)
vllm/model_executor/layers/quantization/compressed_tensors/compressed_tensors_moe.py
+1
-1
@@ -190,7 +190,7 @@ class CompressedTensorsW8A8Fp8MoEMethod(CompressedTensorsMoEMethod):
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assert layer.w13_weight_scale is not None
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shard_size = layer.intermediate_size_per_partition
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max_w13_scales = layer.w13_weight_scale.max(dim=1).values
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- for expert_id in range(layer.num_experts):
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+ for expert_id in range(layer.local_num_experts):
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start = 0
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for shard_id in range(2):
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dq_weight = per_tensor_dequantize(
vllm/model_executor/layers/quantization/fp8.py
+3
-3
@@ -573,11 +573,11 @@ class Fp8MoEMethod(FusedMoEMethodBase):
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# Re-initialize w13_scale because we directly quantize
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# merged w13 weights and generate a single scaling factor.
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layer.w13_weight_scale = torch.nn.Parameter(torch.ones(
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- layer.num_experts,
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+ layer.local_num_experts,
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dtype=torch.float32,
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device=w13_weight.device),
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requires_grad=False)
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- for expert in range(layer.num_experts):
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+ for expert in range(layer.local_num_experts):
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w13_weight[expert, :, :], layer.w13_weight_scale[
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expert] = ops.scaled_fp8_quant(
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layer.w13_weight.data[expert, :, :])
@@ -644,7 +644,7 @@ class Fp8MoEMethod(FusedMoEMethodBase):
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assert layer.w13_weight_scale is not None
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shard_size = layer.intermediate_size_per_partition
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max_w13_scales = layer.w13_weight_scale.max(dim=1).values
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- for expert_id in range(layer.num_experts):
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+ for expert_id in range(layer.local_num_experts):
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start = 0
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for shard_id in range(2):
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dq_weight = per_tensor_dequantize(
vllm/model_executor/layers/quantization/gptq_marlin.py
+1
-1
@@ -153,7 +153,7 @@ class GPTQMarlinConfig(QuantizationConfig):
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def get_quant_method(self, layer: torch.nn.Module,
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prefix: str) -> Optional["QuantizeMethodBase"]:
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if isinstance(layer, FusedMoE):
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- if layer.num_experts > 32:
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+ if layer.local_num_experts > 32:
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# For MoEs with many experts the moe_wna16 kernel is faster
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return MoeWNA16Config.from_config(
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self.full_config).get_quant_method(layer, prefix)
vllm/model_executor/layers/quantization/quark/quark_moe.py
+1
-1
@@ -174,7 +174,7 @@ class QuarkW8A8Fp8MoEMethod(QuarkMoEMethod):
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assert layer.w13_weight_scale is not None
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shard_size = layer.intermediate_size_per_partition
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max_w13_scales = layer.w13_weight_scale.max(dim=1).values
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- for expert_id in range(layer.num_experts):
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+ for expert_id in range(layer.local_num_experts):
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start = 0
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for shard_id in range(2):
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dq_weight = per_tensor_dequantize(