add support for full diff LoRA in multi LoRA merge

This commit is contained in:
silveroxides
2026-01-12 02:36:56 +01:00
parent eaed2003a0
commit 6f3fd0900f
+100 -49
View File
@@ -45,6 +45,7 @@ def detect_lora_format(keys: List[str]) -> Dict:
- Diffusers: *.lora_A.weight, *.lora_B.weight
- PEFT: base_model.model.*.lora_A/B
- ComfyUI native: *.lora_down.weight, *.lora_up.weight
- Full diff: *.diff, *.diff_b (full weight differences, not low-rank)
- Flux/SDXL: Various transformer key patterns
Returns:
@@ -57,6 +58,7 @@ def detect_lora_format(keys: List[str]) -> Dict:
"alpha_suffix": ".alpha",
"has_alpha": False,
"key_count": 0,
"is_full_diff": False, # New flag for full diff format
}
# Check for alpha keys
@@ -64,10 +66,18 @@ def detect_lora_format(keys: List[str]) -> Dict:
format_info["has_alpha"] = len(alpha_keys) > 0
# Detect format by key patterns
sample_keys = keys[:20] # Check first 20 keys
sample_keys = keys[:50] # Check more keys for full_diff detection
# Full diff format: *.diff (NOT .lora_down, just straight weight diff)
if any(k.endswith('.diff') for k in sample_keys):
format_info["format"] = "full_diff"
format_info["down_suffix"] = ".diff" # Used for pairing, but no up
format_info["up_suffix"] = None # No up weight in full diff
format_info["alpha_suffix"] = None
format_info["is_full_diff"] = True
# Kohya/A1111 format: lora_unet_down_blocks_0_*.lora_down.weight
if any('lora_unet_' in k or 'lora_te' in k for k in sample_keys):
elif any('lora_unet_' in k or 'lora_te' in k for k in sample_keys):
format_info["format"] = "kohya"
format_info["down_suffix"] = ".lora_down.weight"
format_info["up_suffix"] = ".lora_up.weight"
@@ -103,32 +113,51 @@ def extract_lora_pairs(keys: List[str], format_info: Dict) -> Dict[str, Dict[str
"""
Group LoRA keys into down/up/alpha pairs.
For full_diff format, groups .diff and .diff_b keys.
Returns:
Dict[block_name, {"down": key, "up": key, "alpha": key}]
For full_diff: {"diff": key, "diff_b": key}
"""
down_suffix = format_info["down_suffix"]
up_suffix = format_info["up_suffix"]
alpha_suffix = format_info["alpha_suffix"]
is_full_diff = format_info.get("is_full_diff", False)
pairs = {}
for key in keys:
if down_suffix in key:
block_name = key.replace(down_suffix, "")
if block_name not in pairs:
pairs[block_name] = {}
pairs[block_name]["down"] = key
elif up_suffix in key:
block_name = key.replace(up_suffix, "")
if block_name not in pairs:
pairs[block_name] = {}
pairs[block_name]["up"] = key
elif alpha_suffix in key or key.endswith('.alpha'):
# Handle various alpha key formats
block_name = key.replace(alpha_suffix, "").replace(".alpha", "")
if block_name not in pairs:
pairs[block_name] = {}
pairs[block_name]["alpha"] = key
if is_full_diff:
# Full diff format: group .diff and .diff_b
for key in keys:
if key.endswith('.diff'):
block_name = key[:-5] # Remove .diff
if block_name not in pairs:
pairs[block_name] = {}
pairs[block_name]["diff"] = key
elif key.endswith('.diff_b'):
block_name = key[:-7] # Remove .diff_b
if block_name not in pairs:
pairs[block_name] = {}
pairs[block_name]["diff_b"] = key
else:
# Standard LoRA format
for key in keys:
if down_suffix and down_suffix in key:
block_name = key.replace(down_suffix, "")
if block_name not in pairs:
pairs[block_name] = {}
pairs[block_name]["down"] = key
elif up_suffix and up_suffix in key:
block_name = key.replace(up_suffix, "")
if block_name not in pairs:
pairs[block_name] = {}
pairs[block_name]["up"] = key
elif alpha_suffix and (alpha_suffix in key or key.endswith('.alpha')):
# Handle various alpha key formats
block_name = key.replace(alpha_suffix, "").replace(".alpha", "")
if block_name not in pairs:
pairs[block_name] = {}
pairs[block_name]["alpha"] = key
return pairs
@@ -1291,41 +1320,63 @@ def merge_multi_loras_via_base(
continue
block_keys = info["pairs"][block_name]
if "down" not in block_keys or "up" not in block_keys:
continue
is_full_diff = info["format_info"].get("is_full_diff", False)
if is_full_diff:
# Full diff format: load .diff directly as the delta
if "diff" not in block_keys:
continue
cpu_diff = info["handler"].get_tensor(block_keys["diff"])
if device == 'cuda':
delta = transfer_to_gpu_pinned(cpu_diff, device, torch.float32)
else:
delta = cpu_diff.to(device=device, dtype=torch.float32)
del cpu_diff
# Determine conv from shape
is_conv = len(delta.shape) == 4
# Apply LoRA weight strength (no alpha scaling for full diff)
effective_scale = info["weight"]
# Load LoRA weights
cpu_down = info["handler"].get_tensor(block_keys["down"])
cpu_up = info["handler"].get_tensor(block_keys["up"])
if device == 'cuda':
lora_down = transfer_to_gpu_pinned(cpu_down, device, torch.float32)
lora_up = transfer_to_gpu_pinned(cpu_up, device, torch.float32)
else:
lora_down = cpu_down.to(device=device, dtype=torch.float32)
lora_up = cpu_up.to(device=device, dtype=torch.float32)
del cpu_down, cpu_up
# Standard LoRA format: compute up @ down
if "down" not in block_keys or "up" not in block_keys:
continue
# Get alpha
if "alpha" in block_keys:
alpha_tensor = info["handler"].get_tensor(block_keys["alpha"])
layer_alpha = float(alpha_tensor.item())
else:
layer_alpha = float(info["network_dim"])
layer_scale = layer_alpha / info["network_dim"] if info["network_dim"] > 0 else 1.0
# Load LoRA weights
cpu_down = info["handler"].get_tensor(block_keys["down"])
cpu_up = info["handler"].get_tensor(block_keys["up"])
if device == 'cuda':
lora_down = transfer_to_gpu_pinned(cpu_down, device, torch.float32)
lora_up = transfer_to_gpu_pinned(cpu_up, device, torch.float32)
else:
lora_down = cpu_down.to(device=device, dtype=torch.float32)
lora_up = cpu_up.to(device=device, dtype=torch.float32)
del cpu_down, cpu_up
# Apply LoRA weight strength
effective_scale = layer_scale * info["weight"]
# Get alpha
if "alpha" in block_keys:
alpha_tensor = info["handler"].get_tensor(block_keys["alpha"])
layer_alpha = float(alpha_tensor.item())
else:
layer_alpha = float(info["network_dim"])
layer_scale = layer_alpha / info["network_dim"] if info["network_dim"] > 0 else 1.0
# Compute delta
is_conv = len(lora_down.shape) == 4
if is_conv:
in_rank, in_size, kernel_size, k_ = lora_down.shape
out_size, out_rank, _, _ = lora_up.shape
delta = lora_up.reshape(out_size, -1) @ lora_down.reshape(in_rank, -1)
delta = delta.reshape(out_size, in_size, kernel_size, kernel_size)
else:
delta = lora_up @ lora_down
del lora_down, lora_up
# Apply LoRA weight strength
effective_scale = layer_scale * info["weight"]
# Compute delta
is_conv = len(lora_down.shape) == 4
if is_conv:
in_rank, in_size, kernel_size, k_ = lora_down.shape
out_size, out_rank, _, _ = lora_up.shape
delta = lora_up.reshape(out_size, -1) @ lora_down.reshape(in_rank, -1)
delta = delta.reshape(out_size, in_size, kernel_size, kernel_size)
else:
delta = lora_up @ lora_down
del lora_down, lora_up
# Accumulate
if combined_delta is None: