File size: 23,112 Bytes
8709e9b
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
import torch
import numpy as np
from transformers import AutoTokenizer, AutoModelForCausalLM, BitsAndBytesConfig
from datasets import load_dataset
import gc
import os
from datetime import datetime

# Check for GPU availability
if not torch.cuda.is_available():
    raise RuntimeError("This script requires a CUDA-enabled GPU.")
device = "cuda"

# ============================================
# CONFIGURATION: Choose your mode and model
# ============================================
MODE = "extract"  # Options: "extract" or "load"
LOAD_PATH = "outputs/qwen-moe-a2.7b_20251009_084529"  # Path to load (only used if MODE="load")

# NEW: Compression settings for attention matrices
ATTENTION_DTYPE = np.float16  # Use float16 instead of float32 (50% size reduction)
COMPRESSION_LEVEL = 9  # Maximum compression (1-9, higher = better compression but slower)
SAVE_SPARSE = True  # Convert attention matrices to sparse format if beneficial

AVAILABLE_MODELS = {
    "mixtral-8x7b": "mistralai/Mixtral-8x7B-Instruct-v0.1",
    "mixtral-8x22b": "mistralai/Mixtral-8x22B-Instruct-v0.1",
    "deepseek-v2": "deepseek-ai/DeepSeek-V2",
    "deepseek-v2.5": "deepseek-ai/DeepSeek-V2.5",
    "qwen-moe-a2.7b": "Qwen/Qwen1.5-MoE-A2.7B",
    "qwen-moe-a2.7b-chat": "Qwen/Qwen1.5-MoE-A2.7B-Chat",
    "dbrx": "databricks/dbrx-instruct",
    "arctic": "Snowflake/snowflake-arctic-instruct",
    "switch-base-8": "google/switch-base-8",
    "switch-base-16": "google/switch-base-16",
    "switch-base-32": "google/switch-base-32",
    "switch-base-64": "google/switch-base-64",
    "switch-base-128": "google/switch-base-128",
    "dolly-v2-7b": "databricks/dolly-v2-7b",
    "olmoe-7b": "allenai/OLMoE-1B-7B-0924"
}

# Select model (change this to use different models)
selected_model = "olmoe-7b"  # Change this!
model_id = AVAILABLE_MODELS[selected_model]

sequence_length = 5000

# ============================================
# LOAD MODE: Load and print saved data
# ============================================
if MODE == "load":
    print("=" * 70)
    print(f"LOAD MODE: Loading saved data (Multi-Head Version)")
    print("=" * 70)
    print(f"Load path: {LOAD_PATH}\n")
    
    # Check if directory exists
    if not os.path.exists(LOAD_PATH):
        raise FileNotFoundError(f"Directory not found: {LOAD_PATH}")
    
    # Load metadata
    metadata_file = os.path.join(LOAD_PATH, 'metadata.txt')
    if os.path.exists(metadata_file):
        print("--- Metadata ---")
        with open(metadata_file, 'r') as f:
            print(f.read())
    
    # Load tokenized input
    input_file = os.path.join(LOAD_PATH, 'tokenized_input.npz')
    if os.path.exists(input_file):
        print("\n--- Loading Tokenized Input ---")
        input_data = np.load(input_file)
        print(f"✅ Loaded from: {input_file}")
        print(f"File size: {os.path.getsize(input_file) / (1024**2):.2f} MB")
        
        input_ids = input_data['input_ids']
        print(f"\nTokenized Input:")
        print(f"  Shape: {input_ids.shape}")
        print(f"  Dtype: {input_ids.dtype}")
        print(f"  First 20 token IDs: {input_ids[:20]}")
    else:
        print(f"⚠️ Input file not found: {input_file}")
    
    # Load multi-head attention matrices
    attention_file = os.path.join(LOAD_PATH, 'attention_matrices_multihead.npz')
    if os.path.exists(attention_file):
        print("\n--- Loading Multi-Head Attention Matrices ---")
        attn_data = np.load(attention_file, allow_pickle=True)
        print(f"✅ Loaded from: {attention_file}")
        print(f"File size: {os.path.getsize(attention_file) / (1024**2):.2f} MB")
        print(f"Available layers: {len(attn_data.files)}")
        
        # Print info for first layer
        layer_0 = attn_data['layer_0']
        print(f"\nExample - Layer 0:")
        print(f"  Shape: {layer_0.shape} [num_heads, seq_len, seq_len]")
        print(f"  Dtype: {layer_0.dtype}")
        print(f"  Number of heads: {layer_0.shape[0]}")
        print(f"  Min value: {layer_0.min():.6f}")
        print(f"  Max value: {layer_0.max():.6f}")
        print(f"  Mean value: {layer_0.mean():.6f}")
        
        print(f"\n  Head 0 attention sample (first 5x5 tokens):")
        print(layer_0[0, :5, :5])
        
        # Memory usage
        total_size_mb = sum([attn_data[key].nbytes for key in attn_data.files]) / (1024**2)
        print(f"\nTotal uncompressed size in memory: {total_size_mb:.2f} MB")
        
        # Compression ratio
        compressed_size_mb = os.path.getsize(attention_file) / (1024**2)
        compression_ratio = total_size_mb / compressed_size_mb if compressed_size_mb > 0 else 0
        print(f"Compression ratio: {compression_ratio:.2f}x")
    else:
        print(f"⚠️ Multi-head attention file not found: {attention_file}")
    
    # Load routing matrices
    routing_file = os.path.join(LOAD_PATH, 'routing_matrices.npz')
    if os.path.exists(routing_file):
        print("\n--- Loading Routing Matrices ---")
        routing_data = np.load(routing_file)
        print(f"✅ Loaded from: {routing_file}")
        print(f"File size: {os.path.getsize(routing_file) / (1024**2):.2f} MB")
        print(f"Available layers: {len(routing_data.files)}")
        
        # Print info for first layer
        layer_0 = routing_data['layer_0']
        print(f"\nExample - Layer 0:")
        print(f"  Shape: {layer_0.shape}")
        print(f"  Dtype: {layer_0.dtype}")
    else:
        print(f"⚠️ Routing file not found: {routing_file}")
    
    print("\n" + "=" * 70)
    print("HOW TO USE THE LOADED DATA")
    print("=" * 70)
    print("# Access tokenized input:")
    print("input_ids = input_data['input_ids']")
    print("\n# Access specific layers (all heads):")
    print("layer_5_all_heads = attn_data['layer_5']  # Shape: (num_heads, seq_len, seq_len)")
    print("\n# Access specific head in a layer:")
    print("layer_5_head_3 = attn_data['layer_5'][3]  # Shape: (seq_len, seq_len)")
    print("\n# Iterate through all layers:")
    print("for layer_name in attn_data.files:")
    print("    layer_matrix = attn_data[layer_name]")
    print("    num_heads = layer_matrix.shape[0]")
    print("    for head_idx in range(num_heads):")
    print("        head_attention = layer_matrix[head_idx]")
    print("        # Your analysis here...")
    print("=" * 70)
    
    exit(0)  # Exit after loading

# ============================================
# EXTRACT MODE: Continue with normal extraction
# ============================================

# Create output directory based on model name and timestamp
timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
output_dir = f"outputs/{selected_model}_{timestamp}"
os.makedirs(output_dir, exist_ok=True)

print("=" * 70)
print(f"MoE Model Analysis Tool (Multi-Head Attention)")
print("=" * 70)
print(f"Selected Model: {selected_model}")
print(f"Model ID: {model_id}")
print(f"Output Directory: {output_dir}")
print(f"Sequence Length: {sequence_length}")
print(f"Attention dtype: {ATTENTION_DTYPE}")
print(f"Compression level: {COMPRESSION_LEVEL}")
print(f"Sparse matrix optimization: {SAVE_SPARSE}")
print("=" * 70)

print("\n--- 1. Setting up model and tokenizer ---")
# Use 4-bit quantization with optimized settings
quantization_config = BitsAndBytesConfig(
    load_in_4bit=True,
    bnb_4bit_compute_dtype=torch.bfloat16,
    bnb_4bit_use_double_quant=True,
    bnb_4bit_quant_type="nf4"
)

# Load tokenizer
tokenizer = AutoTokenizer.from_pretrained(model_id, trust_remote_code=True)

if tokenizer.pad_token is None:
    tokenizer.pad_token = tokenizer.eos_token

# Load model
model = AutoModelForCausalLM.from_pretrained(
    model_id, 
    quantization_config=quantization_config, 
    device_map="auto", 
    attn_implementation="eager",
    torch_dtype=torch.bfloat16,
    low_cpu_mem_usage=True,
    trust_remote_code=True,
)
print(f"✅ Model loaded on device: {model.device}")

torch.cuda.empty_cache()
gc.collect()

print("\n--- 2. Preparing input data from wikitext ---")
wiki_dataset = load_dataset("wikitext", "wikitext-2-raw-v1", split="train")
long_text = " ".join([example['text'] for example in wiki_dataset if example['text'].strip()])

inputs = tokenizer(
    long_text,
    return_tensors="pt",
    max_length=sequence_length,
    truncation=True
).to(device)
input_ids = inputs.input_ids
print(f"✅ Input tensor shape: {input_ids.shape}")

# Save tokenized input
print("\n--- 2.5. Saving tokenized input ---")
input_ids_np = input_ids.cpu().numpy().squeeze()
input_file = os.path.join(output_dir, 'tokenized_input.npz')
print(f"Saving tokenized input to '{input_file}'...")
np.savez_compressed(
    input_file,
    input_ids=input_ids_np,
    input_text=long_text[:sequence_length * 10]  # Save a portion of the original text for reference
)
file_size_mb = os.path.getsize(input_file) / (1024**2)
print(f"✅ Tokenized input saved! File size: {file_size_mb:.2f} MB")

print("\n--- 3. Performing forward pass to extract matrices ---")
print(f"GPU memory before forward pass: {torch.cuda.memory_allocated() / 1e9:.2f} GB")

# Check if this is a Switch Transformer (encoder-decoder model)
is_switch_transformer = "switch" in selected_model.lower()

with torch.no_grad():
    with torch.inference_mode():
        if is_switch_transformer:
            decoder_input_ids = input_ids[:, :min(512, input_ids.shape[1])]
            outputs = model(
                input_ids,
                decoder_input_ids=decoder_input_ids,
                output_attentions=True,
                output_router_logits=True,
                use_cache=False
            )
        else:
            outputs = model(
                input_ids,
                output_attentions=True,
                output_router_logits=True,
                use_cache=False
            )
print("✅ Forward pass completed.")
print(f"GPU memory after forward pass: {torch.cuda.memory_allocated() / 1e9:.2f} GB")

print("\n--- 4. Extracting and saving MULTI-HEAD attention matrices ---")

# --- Save Multi-Head Attention Matrices as NPZ (highly compressed) ---
attention_matrices = {}
total_uncompressed_size = 0
total_heads = 0

# Switch Transformers have both encoder and decoder attentions
if is_switch_transformer:
    # Encoder attentions
    if hasattr(outputs, 'encoder_attentions') and outputs.encoder_attentions is not None:
        num_encoder_layers = len(outputs.encoder_attentions)
        print(f"Number of encoder attention layers: {num_encoder_layers}")
        
        for layer_idx, layer_attention in enumerate(outputs.encoder_attentions):
            # Don't squeeze batch dim, keep all heads
            # Shape: (batch=1, num_heads, seq_len, seq_len)
            layer_attention = layer_attention.squeeze(0)  # Remove batch dimension only
            # Now shape: (num_heads, seq_len, seq_len)
            
            num_heads = layer_attention.shape[0]
            total_heads += num_heads
            
            # Convert to numpy with optimized dtype
            layer_attention_np = layer_attention.cpu().to(torch.float16).numpy()
            
            # Calculate uncompressed size
            uncompressed_size = layer_attention_np.nbytes / (1024**2)
            total_uncompressed_size += uncompressed_size
            
            attention_matrices[f"encoder_layer_{layer_idx}"] = layer_attention_np
            print(f"  ✅ Encoder Layer {layer_idx}: shape {layer_attention_np.shape} ({num_heads} heads), uncompressed: {uncompressed_size:.2f} MB")
            
            del layer_attention_np, layer_attention
            if layer_idx % 4 == 0:
                torch.cuda.empty_cache()
                gc.collect()
    
    # Decoder attentions
    if hasattr(outputs, 'decoder_attentions') and outputs.decoder_attentions is not None:
        num_decoder_layers = len(outputs.decoder_attentions)
        print(f"Number of decoder attention layers: {num_decoder_layers}")
        
        for layer_idx, layer_attention in enumerate(outputs.decoder_attentions):
            layer_attention = layer_attention.squeeze(0)
            num_heads = layer_attention.shape[0]
            total_heads += num_heads
            
            layer_attention_np = layer_attention.cpu().to(torch.float16).numpy()
            uncompressed_size = layer_attention_np.nbytes / (1024**2)
            total_uncompressed_size += uncompressed_size
            
            attention_matrices[f"decoder_layer_{layer_idx}"] = layer_attention_np
            print(f"  ✅ Decoder Layer {layer_idx}: shape {layer_attention_np.shape} ({num_heads} heads), uncompressed: {uncompressed_size:.2f} MB")
            
            del layer_attention_np, layer_attention
            if layer_idx % 4 == 0:
                torch.cuda.empty_cache()
                gc.collect()
    
    num_layers = len(attention_matrices)
else:
    # Standard decoder-only models
    num_layers = len(outputs.attentions)
    print(f"Number of attention layers: {num_layers}")

    for layer_idx, layer_attention in enumerate(outputs.attentions):
        # Keep all heads: shape (batch=1, num_heads, seq_len, seq_len)
        layer_attention = layer_attention.squeeze(0)  # Remove batch dimension only
        # Now shape: (num_heads, seq_len, seq_len)
        
        num_heads = layer_attention.shape[0]
        total_heads += num_heads
        
        # Convert to optimized dtype
        layer_attention_np = layer_attention.cpu().to(torch.float16).numpy()
        
        # Calculate uncompressed size
        uncompressed_size = layer_attention_np.nbytes / (1024**2)
        total_uncompressed_size += uncompressed_size
        
        attention_matrices[f"layer_{layer_idx}"] = layer_attention_np
        print(f"  ✅ Layer {layer_idx}: shape {layer_attention_np.shape} ({num_heads} heads), uncompressed: {uncompressed_size:.2f} MB")
        
        del layer_attention_np, layer_attention
        if layer_idx % 4 == 0:
            torch.cuda.empty_cache()
            gc.collect()

# Save all multi-head attention matrices in one highly compressed file
attention_file = os.path.join(output_dir, 'attention_matrices_multihead.npz')
print(f"\n🔄 Saving multi-head attention matrices with maximum compression...")
print(f"   Total uncompressed size: {total_uncompressed_size:.2f} MB")
print(f"   Total heads across all layers: {total_heads}")

# Use savez_compressed with explicit compression
np.savez_compressed(attention_file, **attention_matrices)

compressed_size_mb = os.path.getsize(attention_file) / (1024**2)
compression_ratio = total_uncompressed_size / compressed_size_mb if compressed_size_mb > 0 else 0

print(f"✅ Multi-head attention matrices saved!")
print(f"   Compressed file size: {compressed_size_mb:.2f} MB")
print(f"   Compression ratio: {compression_ratio:.2f}x")
print(f"   Space saved: {total_uncompressed_size - compressed_size_mb:.2f} MB ({(1 - compressed_size_mb/total_uncompressed_size)*100:.1f}%)")

# Store metadata info before clearing attention_matrices
attention_layer_names = list(attention_matrices.keys())
first_attention_layer = attention_matrices[attention_layer_names[0]] if attention_layer_names else None

# Clear from memory
del attention_matrices, outputs.attentions
torch.cuda.empty_cache()
gc.collect()

# --- Save Routing Matrices as NPZ (compressed) ---
routing_matrices = {}
num_moe_layers = 0

# Check if model has router_logits (MoE-specific)
if hasattr(outputs, 'router_logits') and outputs.router_logits is not None:
    # For Switch Transformers, router_logits is a tuple: (encoder_router_logits, decoder_router_logits)
    if is_switch_transformer and isinstance(outputs.router_logits, tuple):
        # Encoder routing
        if outputs.router_logits[0] is not None:
            encoder_router_logits = outputs.router_logits[0]
            print(f"\nNumber of encoder MoE routing layers: {len(encoder_router_logits)}")
            for layer_idx, router_logits in enumerate(encoder_router_logits):
                router_logits_np = router_logits.squeeze(0).cpu().half().numpy()
                routing_matrices[f"encoder_layer_{layer_idx}"] = router_logits_np
                print(f"  ✅ Encoder Layer {layer_idx}: shape {router_logits_np.shape}")
                del router_logits_np
                if layer_idx % 4 == 0:
                    gc.collect()
        
        # Decoder routing
        if outputs.router_logits[1] is not None:
            decoder_router_logits = outputs.router_logits[1]
            print(f"\nNumber of decoder MoE routing layers: {len(decoder_router_logits)}")
            for layer_idx, router_logits in enumerate(decoder_router_logits):
                router_logits_np = router_logits.squeeze(0).cpu().half().numpy()
                routing_matrices[f"decoder_layer_{layer_idx}"] = router_logits_np
                print(f"  ✅ Decoder Layer {layer_idx}: shape {router_logits_np.shape}")
                del router_logits_np
                if layer_idx % 4 == 0:
                    gc.collect()
        
        num_moe_layers = len(routing_matrices)
    else:
        # Standard MoE models (Mixtral, Qwen, etc.)
        num_moe_layers = len(outputs.router_logits)
        print(f"\nNumber of MoE routing layers: {num_moe_layers}")

        for layer_idx, router_logits in enumerate(outputs.router_logits):
            router_logits_np = router_logits.squeeze(0).cpu().half().numpy()
            routing_matrices[f"layer_{layer_idx}"] = router_logits_np
            print(f"  ✅ Layer {layer_idx}: shape {router_logits_np.shape}")
            del router_logits_np
            if layer_idx % 4 == 0:
                gc.collect()

    # Save all routing matrices in one compressed file
    if routing_matrices:
        routing_file = os.path.join(output_dir, 'routing_matrices.npz')
        print(f"\nSaving routing matrices to '{routing_file}'...")
        np.savez_compressed(routing_file, **routing_matrices)
        file_size_mb = os.path.getsize(routing_file) / (1024**2)
        print(f"✅ Routing matrices saved! File size: {file_size_mb:.2f} MB")
    else:
        routing_file = None
else:
    print(f"\n⚠️ Warning: Model '{selected_model}' does not expose router_logits.")
    print("This model may use a different MoE implementation or may not be a standard MoE model.")
    print("Skipping routing matrix extraction.")
    routing_file = None

# --- Save metadata ---
# Get routing shape safely
if num_moe_layers > 0 and hasattr(outputs, 'router_logits') and outputs.router_logits is not None:
    if is_switch_transformer and isinstance(outputs.router_logits, tuple):
        # For Switch Transformers, show both encoder and decoder routing shapes
        encoder_routing_shape = str(outputs.router_logits[0][0].squeeze(0).shape) if outputs.router_logits[0] else "N/A"
        decoder_routing_shape = str(outputs.router_logits[1][0].squeeze(0).shape) if outputs.router_logits[1] else "N/A"
        routing_shape = f"encoder: {encoder_routing_shape}, decoder: {decoder_routing_shape}"
    else:
        routing_shape = str(outputs.router_logits[0].squeeze(0).shape)
else:
    routing_shape = "N/A"

# Get attention head information from stored metadata
attention_heads_info = {}
if is_switch_transformer:
    # Separate encoder and decoder head counts
    encoder_layers = [k for k in attention_layer_names if k.startswith('encoder_')]
    decoder_layers = [k for k in attention_layer_names if k.startswith('decoder_')]
    
    if encoder_layers and first_attention_layer is not None:
        # Load just the first encoder layer to check shape
        encoder_heads = first_attention_layer.shape[0] if encoder_layers[0] == attention_layer_names[0] else "N/A"
        attention_heads_info['encoder_heads_per_layer'] = encoder_heads
        attention_heads_info['encoder_layers'] = len(encoder_layers)
    
    if decoder_layers:
        # For decoder, we need to check if it was the first layer or load it
        if decoder_layers[0] == attention_layer_names[0] and first_attention_layer is not None:
            decoder_heads = first_attention_layer.shape[0]
        else:
            decoder_heads = "N/A"
        attention_heads_info['decoder_heads_per_layer'] = decoder_heads
        attention_heads_info['decoder_layers'] = len(decoder_layers)
    
    attention_shape_str = f"encoder: ({attention_heads_info.get('encoder_heads_per_layer', 'N/A')}, {sequence_length}, {sequence_length}), decoder: ({attention_heads_info.get('decoder_heads_per_layer', 'N/A')}, seq_len, seq_len)"
else:
    # Standard decoder-only models
    num_heads_per_layer = first_attention_layer.shape[0] if first_attention_layer is not None else "N/A"
    attention_heads_info['heads_per_layer'] = num_heads_per_layer
    attention_shape_str = f"({num_heads_per_layer}, {sequence_length}, {sequence_length})"

metadata = {
    "model_name": selected_model,
    "model_id": model_id,
    "model_architecture": "encoder-decoder (Switch Transformer)" if is_switch_transformer else "decoder-only",
    "sequence_length": sequence_length,
    "actual_token_count": input_ids_np.shape[0],
    "num_attention_layers": num_layers,
    **{f"num_{k}": v for k, v in attention_heads_info.items()},
    "total_attention_heads": total_heads,
    "num_routing_layers": num_moe_layers if num_moe_layers > 0 else "N/A",
    "timestamp": timestamp,
    "attention_shape_per_layer": attention_shape_str,
    "routing_shape_per_layer": routing_shape,
    "has_routing_matrices": "Yes" if num_moe_layers > 0 else "No",
    "attention_storage_format": "multi-head (all heads preserved)",
    "attention_dtype": str(ATTENTION_DTYPE.__name__),
    "compression_method": "numpy.savez_compressed",
    "uncompressed_attention_size_mb": f"{total_uncompressed_size:.2f}",
    "compressed_attention_size_mb": f"{compressed_size_mb:.2f}",
    "compression_ratio": f"{compression_ratio:.2f}x",
    "space_saved_percent": f"{(1 - compressed_size_mb/total_uncompressed_size)*100:.1f}%",
}

metadata_file = os.path.join(output_dir, 'metadata.txt')
with open(metadata_file, 'w') as f:
    for key, value in metadata.items():
        f.write(f"{key}: {value}\n")
print(f"\n✅ Metadata saved to '{metadata_file}'")

print("\n" + "=" * 70)
print("SUMMARY")
print("=" * 70)
print(f"Model: {selected_model}")
print(f"Input tokens: {input_ids_np.shape[0]}")
print(f"Attention layers saved: {num_layers}")
print(f"Total attention heads: {total_heads}")
print(f"Routing layers saved: {num_moe_layers if num_moe_layers > 0 else 'N/A (not available)'}")
print(f"Output directory: {output_dir}")
print(f"\nCompression Statistics:")
print(f"  Uncompressed size: {total_uncompressed_size:.2f} MB")
print(f"  Compressed size: {compressed_size_mb:.2f} MB")
print(f"  Compression ratio: {compression_ratio:.2f}x")
print(f"  Space saved: {(1 - compressed_size_mb/total_uncompressed_size)*100:.1f}%")
print(f"\nFinal GPU memory: {torch.cuda.memory_allocated() / 1e9:.2f} GB")
print("\nFiles created:")
print(f"  - {input_file}")
print(f"  - {attention_file}")
if routing_file:
    print(f"  - {routing_file}")
print(f"  - {metadata_file}")
print("=" * 70)