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---
configs:
- config_name: default
  data_files:
  - split: runtime_filtered
    path: "backend_bench_problems_runtime_filtered.parquet"
  - split: runtime_filtered_scaling_factor_2
    path: "backend_bench_problems_runtime_filtered_threshhold_2.parquet"
  - split: benchmark
    path: "backend_bench_problems.parquet"
---

# Understanding Trace Files in BackendBench

## Format
Trace files capture PyTorch operations and their arguments from real model executions:

```
Operator: operation_name
cnt: count, serialized_arguments
cnt: count, serialized_arguments
...
```

## Structure

**Operator line**: Specifies the PyTorch operation
```
Operator: aten.add.Tensor
Operator: aten.relu.default
Operator: aten.linear.default
```

**Count lines**: Show how often each argument combination was used
```
cnt: 42, ((T([10, 20], f16), T([10, 20], f16)), {})
cnt: 0, ((T([5, 5], f32), T([5, 5], f32)), {})
```

## Reading Count Lines

**Count `42`**: This argument combination appeared 42 times in traced models
- **`cnt: 0`** = Synthetic/generated arguments (not from real models)
- **`cnt: >0`** = Real usage frequency from model traces

**Arguments**: Same format as serialized arguments - `((args), {kwargs})`

## Complete Example

```
Operator: aten.add.Tensor
cnt: 156, ((T([1, 512, 768], f16), T([1, 512, 768], f16)), {})
cnt: 89, ((T([32, 128], f32), T([32, 128], f32)), {})
cnt: 0, ((T([10, 10], f16), T([10, 10], f16)), {})

Operator: aten.relu.default  
cnt: 234, ((T([64, 256], f16),), {})
```

This shows:
- `aten.add.Tensor` called 156 times with 1×512×768 tensors
- Same operation called 89 times with 32×128 tensors  
- One synthetic test case (cnt: 0)
- `aten.relu.default` called 234 times with 64×256 tensor

## Interpretation
Trace files provide real-world operation usage patterns, showing which tensor shapes and operations are most common in actual PyTorch models. These are fairly useful for debugging.

**Note: These may be deprecated in the future, but are described as they are currently included in the dataset / codebase.**


# Understanding Serialized Arguments in BackendBench
## Format
BackendBench stores function arguments as strings containing all parameters needed to reproduce PyTorch operations:

```
((arg1, arg2, ...), {'key1': val1, 'key2': val2})
```

## Tensor Representation
Tensors use the format `T([shape], dtype)` or `T([shape], dtype, [stride])`:

```python
T([10, 20], f32)           # 10×20 float32 tensor
T([1, 512, 768], f16)      # 1×512×768 float16 tensor  
T([64], i32)               # 64-element int32 vector
```

**Data types**: `f16/f32/f64` (float), `bf16` (bfloat16), `i32/i64` (int), `b8` (bool)

## Complete Examples

**Single tensor argument:**
```python
((T([48, 24, 28, 28], f16),), {})
```
= Function called with one 48×24×28×28 float16 tensor, no keyword arguments

**Multiple tensors:**
```python
((T([8, 8, 8, 8, 8], f16), T([8, 8, 8, 8, 8], f16)), {})
```
= Function with two identical 5D tensors

**Mixed arguments:**
```python
((T([128, 256], f16), [1024, 249, 249]), {'dtype': torch.float16, 'device': 'cuda'})
```
= Function with tensor, list, and keyword arguments

**Complex nested:**
```python
(([T([5, 5], f32), T([3, 3], i64), 42],), {'weight': T([3, 3], f32)})
```
= Function with list containing tensors and numbers, plus tensor keyword argument

## Argument Types
- **Tensors**: `T([shape], dtype)` format
- **Lists**: `[item1, item2, ...]` (can contain tensors)
- **Primitives**: `42`, `'hello'`, `True`, `None`
- **PyTorch objects**: `torch.float16`, `torch.strided`

## Acknowledgements
We are extremely grateful for the folks working on [TritonBench](https://github.com/pytorch-labs/tritonbench/tree/main) for these traces and intuitive format