feat: Added comprehensive perf benchmark script

Signed-off-by: Anurag Dixit <[email protected]>

Author: Anurag Dixit

Diff for: examples/benchmark/py/README.md

@@ -0,0 +1,76 @@
+# Performance Benchmarking
+
+This is a comprehensive Python benchmark suite to run perf runs using different supported backends. Following backends are supported:
+
+1. Torch
+2. Torch-TensorRT
+3. TensorRT
+
+Note: Please note that for ONNX models, user can convert the ONNX model to TensorRT serialized engine and then use this package.
+
+## Structure
+
+```
+./
+├── config
+│   ├── vgg16_trt.yml
+│   └── vgg16.yml
+├── models
+├── perf_run.py
+└── README.md
+```
+
+Please save your configuration files at config directory. Similarly, place your model files at models path.
+
+## Usage
+
+To run the benchmark for a given configuration file:
+
+```
+python perf_run.py --config=config/vgg16.yml
+```
+
+## Configuration
+
+There are two sample configuration files added. 
+
+* vgg16.yml demonstrates a configuration with all the supported backends (Torch, Torch-TensorRT, TensorRT)
+* vgg16_trt.yml demonstrates how to use an external TensorRT serialized engine file directly.
+
+
+### Supported fields
+
+| Name | Supported Values | Description |
+| --- | --- | --- |
+| backend | all, torch, torch_tensorrt, tensorrt | Supported backends for inference |
+| input | - | Input binding names. Expected to list shapes of each input bindings |
+| model | - | Configure the model filename and name |
+| filename | - | Model file name to load from disk |
+| name | - | Model name | 
+| runtime | - | Runtime configurations | 
+| device | 0 | Target device ID to run inference. Range depends on available GPUs |
+| precision | fp32, fp16 or half, int8 | Target precision to run inference |
+
+
+Additional sample use case:
+
+```
+backend: 
+  - torch
+  - torch_tensorrt
+  - tensorrt
+input: 
+  input0: 
+    - 3
+    - 224
+    - 224
+  num_of_input: 1
+model: 
+  filename: model.plan
+  name: vgg16
+runtime: 
+  device: 0
+  precision: 
+    - fp32
+    - fp16
+```

Diff for: examples/benchmark/py/config/vgg16.yml

@@ -1,7 +1,6 @@
 --- 
 backend: 
-  - torch
-  - torch_tensorrt
+  - all
 input: 
   input0: 
     - 1

Diff for: examples/benchmark/py/config/vgg16_trt.yml

@@ -0,0 +1,17 @@
+--- 
+backend: 
+  - tensorrt
+input: 
+  input0: 
+    - 3
+    - 224
+    - 224
+  num_of_input: 1
+model: 
+  filename: model.plan
+  name: vgg16
+runtime: 
+  device: 0
+  precision: 
+    - fp32
+    - fp16