Document how to profile multiple LoRA adapters (#676)

Author: the-david-oy

src/c++/perf_analyzer/genai-perf/README.md

@@ -345,14 +345,16 @@ Show the help message and exit.
 ##### `-m <list>`
 ##### `--model <list>`
 
-The name of the model to benchmark. (default: `None`)
+The names of the models to benchmark.
+A single model is recommended, unless you are
+[profiling multiple LoRA adapters](docs/lora.md). (default: `None`)
 
 ##### `--model-selection-strategy {round_robin, random}`
 
-When multiple model are specified, this is how a specific model
-should be assigned to a prompt.  round_robin means that ith prompt in the
-list gets assigned to i mod len(models).  random means that assignment is
-uniformly random (default: `round_robin`)
+When multiple models are specified, this is how a specific model
+is assigned to a prompt. Round robin means that each model receives
+a request in order. Random means that assignment is uniformly random
+(default: `round_robin`)
 
 ##### `--backend {tensorrtllm,vllm}`
 

src/c++/perf_analyzer/genai-perf/docs/lora.md

@@ -0,0 +1,53 @@
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+
+# Profiling Multiple LoRA Adapters
+GenAI-Perf allows you to profile multiple LoRA adapters on top of a base model.
+
+## Selecting LoRA Adapters
+To do this, list multiple adapters after the model name option `-m`:
+
+```bash
+genai-perf -m lora_adapter1 lora_adapter2 lora_adapter3
+```
+
+## Choosing a Strategy for Selecting Models
+When profiling with multiple models, you can specify how the models should be
+assigned to prompts using the `--model-selection-strategy` option:
+
+```bash
+genai-perf \
+    -m lora_adapter1 lora_adapter2 lora_adapter3 \
+    --model-selection-strategy round_robin
+```
+
+This setup will cycle through the lora_adapter1, lora_adapter2, and
+lora_adapter3 models in a round-robin manner for each prompt.
+
+For more details on additional options and configurations, refer to the
+[Command Line Options section](../README.md#command-line-options) in the README.