add instructions about getting mmlu score for instruct models

examples/models/llama2/README.md

@@ -49,7 +49,7 @@ We employed 4-bit groupwise per token dynamic quantization of all the linear lay
 
 We evaluated UncycloText perplexity using [LM Eval](https://github.com/EleutherAI/lm-evaluation-harness). Please note that LM Eval reports perplexity normalized by word count instead of token count. You may see different perplexity for UncycloText from other sources if they implement it differntly. More details could be found [here](https://github.com/EleutherAI/lm-evaluation-harness/issues/2301).
 
-Below are the results for two different groupsizes, with max_seq_len 2048, and 1000 samples.
+Below are the results for two different groupsizes, with max_seq_length 2048, and limit 1000.
 
 |Model | Baseline (FP32) | Groupwise 4-bit (128) | Groupwise 4-bit (256)
 |--------|-----------------| ---------------------- | ---------------
@@ -280,12 +280,32 @@ tokenizer.path=<path_to_checkpoint_folder>/tokenizer.model
 
 > Forewarning: Model evaluation without a GPU may take a long time, especially on larger models.
 
-Using the same arguments from above
+We use [LM Eval](https://github.com/EleutherAI/lm-evaluation-harness) to evaluate model accuracy.
+
+For base models, use the following example command to calculate its perplexity based on UncycloText.
 ```
-python -m examples.models.llama2.eval_llama -c <checkpoint.pth> -p <params.json> -t <tokenizer.model/bin> -d fp32 --max_seq_len <max sequence length> --limit <number of samples>
+python -m examples.models.llama2.eval_llama \
+	-c <checkpoint.pth> \
+	-p <params.json> \
+	-t <tokenizer.model/bin> \
+	-kv \
+	-d <checkpoint dtype> \
+	--max_seq_len <max sequence length> \
+	--limit <number of samples>
 ```
 
-The Uncyclotext results generated above used: `{max_seq_len: 2048, limit: 1000}`
+For instruct models, use the following example command to calculate its MMLU score.
+```
+python -m examples.models.llama2.eval_llama \
+	-c <checkpoint.pth> \
+	-p <params.json> \
+	-t <tokenizer.model/bin> \
+	-kv \
+	-d <checkpoint dtype> \
+	--tasks mmlu \
+	--num_fewshot 5 \
+	--max_seq_len <max sequence length>
+```
 
 ## Step 4: Run on your computer to validate