Simplify creating parameters

examples/mistral/mixtral_fused.py

@@ -0,0 +1,75 @@
+import gc
+import torch
+from tqdm import tqdm
+from axolotl.monkeypatch.moe.moe import SparseMoeBlock
+from transformers import AutoTokenizer, TextStreamer
+from transformers.models.mixtral.modeling_mixtral import MixtralSparseMoeBlock, MixtralForCausalLM, MixtralConfig
+
+def compute_memory_used_pct(device):
+    memory_used = torch.cuda.max_memory_allocated(device) / (1024**3)
+    memory_pct = (
+        memory_used
+        / (torch.cuda.get_device_properties(device).total_memory / (1024**3))
+        * 100
+    )
+    return memory_pct
+
+model_path = "mistralai/Mixtral-8x7B-Instruct-v0.1"
+
+# Load model
+config = MixtralConfig.from_pretrained(model_path, max_position_embeddings=2048, use_cache=False)
+model = MixtralForCausalLM.from_pretrained(
+    model_path,
+    config=config,
+    device_map="auto",
+    low_cpu_mem_usage=True,
+    torch_dtype=torch.float16,
+)
+modules = {k:v for k,v in model.named_modules() if isinstance(v, MixtralSparseMoeBlock)}
+
+for device_index in range(torch.cuda.device_count()):
+    device_memory_pct = compute_memory_used_pct(device_index)
+    print(device_index, device_memory_pct)
+
+with tqdm(modules.items(), desc="scatter moe") as pbar:
+    for i, (name, module) in enumerate(pbar):
+        smoe = SparseMoeBlock(
+            experts=module.experts,
+            gate=module.gate,
+            hidden_dim=module.hidden_dim,
+            ffn_dim=module.ffn_dim,
+            num_experts=module.num_experts,
+            top_k=module.top_k,
+        )
+        old_module = model.model.layers[i].block_sparse_moe
+        setattr(model.model.layers[i], "block_sparse_moe", smoe)
+        del old_module
+        torch.cuda.empty_cache()
+        gc.collect()
+        torch.cuda.empty_cache()
+
+        for device_index in range(torch.cuda.device_count()):
+            device_memory_pct = compute_memory_used_pct(device_index)
+            print(device_index, device_memory_pct)
+
+tokenizer = AutoTokenizer.from_pretrained(model_path)
+streamer = TextStreamer(tokenizer, skip_prompt=True, skip_special_tokens=True)
+
+# Convert prompt to tokens
+prompt_template = "[INST] {prompt} [/INST]"
+
+prompt = "You're standing on the surface of the Earth. "\
+        "You walk one mile south, one mile west and one mile north. "\
+        "You end up exactly where you started. Where are you?"
+
+tokens = tokenizer(
+    prompt_template.format(prompt=prompt), 
+    return_tensors='pt'
+).input_ids.cuda()
+
+# Generate output
+generation_output = model.generate(
+    tokens, 
+    streamer=streamer,
+    max_new_tokens=512
+)

src/axolotl/monkeypatch/moe/linear.py

@@ -123,9 +123,11 @@ def parallel_linear(inputs, expert_weights, k,
     return results
 
 class ParallelExperts(nn.Module):
-    def __init__(self, num_experts, input_size, output_size) -> None:
+    def __init__(self, num_experts, input_size, output_size, device) -> None:
         super().__init__()
-        self.weight = nn.Parameter(torch.empty(num_experts, output_size, input_size))
+        self.weight = nn.Parameter(
+            torch.empty(num_experts, output_size, input_size, device=device)
+        )
         self.num_experts = num_experts
         self.input_size = input_size
         self.output_size = output_size

src/axolotl/monkeypatch/moe/mlp.py

@@ -4,6 +4,7 @@ https://github.com/shawntan/scattermoe
 https://arxiv.org/abs/2403.08245
 """
 
+import gc
 import torch
 from torch import nn
 
@@ -14,7 +15,7 @@ from axolotl.monkeypatch.moe.linear import ParallelExperts
 class FusedExperts(nn.Module):
     def __init__(
         self,
-        experts=None,
+        experts: nn.ModuleList =None,
         hidden_dim=128,
         ffn_dim=512,
         num_experts=8,
@@ -27,31 +28,26 @@ class FusedExperts(nn.Module):
         """
         super(FusedExperts, self).__init__()
 
+        device = experts[0].w1.weight.device
         self.num_experts = num_experts
         self.hidden_dim = hidden_dim
         self.ffn_dim = ffn_dim
-        self.experts = ParallelExperts(num_experts, hidden_dim, 2 * ffn_dim)
-        self.output_experts = ParallelExperts(num_experts, ffn_dim, hidden_dim)
+        self.experts = ParallelExperts(num_experts, hidden_dim, 2 * ffn_dim, device=device)
+        self.output_experts = ParallelExperts(num_experts, ffn_dim, hidden_dim, device=device)
         self.top_k = min(top_k, self.num_experts)
         self.activation = activation
 
-        # parallelize all w1 and w3 computation by concat + stack
         with torch.no_grad():
-            torch.stack(
-                [
-                    torch.cat([experts[i].w1.weight, experts[i].w3.weight], dim=0)
-                    for i in range(len(experts))
-                ],
-                dim=0,
-                out=self.experts.weight.data,
-            )
-
-            # parallelize all w2 computation by stack
-            torch.stack(
-                [expert.w2.weight for expert in experts],
-                dim=0,
-                out=self.output_experts.weight.data,
-            )
+            for i in range(len(experts)):
+                self.experts.weight.data[i].copy_(
+                    torch.cat(
+                        [experts[i].w1.weight.detach(), experts[i].w3.weight.detach()],
+                        dim=0
+                    )
+                )
+                self.output_experts.weight.data[i].copy_(
+                    experts[i].w2.weight.detach()
+                )
 
     def forward(
         self, x: torch.Tensor, routing_weights: torch.Tensor, selected_experts: torch.Tensor