Llama v3. (#2085)

* Llama v3.

* Tweak the default params + handle special tokens.

* Small tweak.

candle-examples/examples/llama/main.rs

@@ -31,6 +31,7 @@ const DEFAULT_PROMPT: &str = "My favorite theorem is ";
 enum Which {
     V1,
     V2,
+    V3,
     #[value(name = "solar-10.7b")]
     Solar10_7B,
     #[value(name = "tiny-llama-1.1b-chat")]
@@ -45,8 +46,8 @@ struct Args {
     cpu: bool,
 
     /// The temperature used to generate samples.
-    #[arg(long)]
-    temperature: Option<f64>,
+    #[arg(long, default_value_t = 0.8)]
+    temperature: f64,
 
     /// Nucleus sampling probability cutoff.
     #[arg(long)]
@@ -90,11 +91,11 @@ struct Args {
     use_flash_attn: bool,
 
     /// Penalty to be applied for repeating tokens, 1. means no penalty.
-    #[arg(long, default_value_t = 1.0)]
+    #[arg(long, default_value_t = 1.1)]
     repeat_penalty: f32,
 
     /// The context size to consider for the repeat penalty.
-    #[arg(long, default_value_t = 64)]
+    #[arg(long, default_value_t = 128)]
     repeat_last_n: usize,
 }
 
@@ -120,11 +121,12 @@ fn main() -> Result<()> {
         Some(dtype) => bail!("Unsupported dtype {dtype}"),
         None => DType::F16,
     };
-    let (llama, tokenizer_filename, mut cache) = {
+    let (llama, tokenizer_filename, mut cache, config) = {
         let api = Api::new()?;
         let model_id = args.model_id.unwrap_or_else(|| match args.which {
             Which::V1 => "Narsil/amall-7b".to_string(),
             Which::V2 => "meta-llama/Llama-2-7b-hf".to_string(),
+            Which::V3 => "meta-llama/Meta-Llama-3-8B".to_string(),
             Which::Solar10_7B => "upstage/SOLAR-10.7B-v1.0".to_string(),
             Which::TinyLlama1_1BChat => "TinyLlama/TinyLlama-1.1B-Chat-v1.0".to_string(),
         });
@@ -138,7 +140,7 @@ fn main() -> Result<()> {
         let config = config.into_config(args.use_flash_attn);
 
         let filenames = match args.which {
-            Which::V1 | Which::V2 | Which::Solar10_7B => {
+            Which::V1 | Which::V2 | Which::V3 | Which::Solar10_7B => {
                 candle_examples::hub_load_safetensors(&api, "model.safetensors.index.json")?
             }
             Which::TinyLlama1_1BChat => vec![api.get("model.safetensors")?],
@@ -146,10 +148,12 @@ fn main() -> Result<()> {
         let cache = model::Cache::new(!args.no_kv_cache, dtype, &config, &device)?;
 
         let vb = unsafe { VarBuilder::from_mmaped_safetensors(&filenames, dtype, &device)? };
-        (Llama::load(vb, &config)?, tokenizer_filename, cache)
+        (Llama::load(vb, &config)?, tokenizer_filename, cache, config)
     };
     let tokenizer = Tokenizer::from_file(tokenizer_filename).map_err(E::msg)?;
-    let eos_token_id = tokenizer.token_to_id(EOS_TOKEN);
+    let eos_token_id = config
+        .eos_token_id
+        .or_else(|| tokenizer.token_to_id(EOS_TOKEN));
     let prompt = args.prompt.as_ref().map_or(DEFAULT_PROMPT, |p| p.as_str());
     let mut tokens = tokenizer
         .encode(prompt, true)
@@ -160,7 +164,7 @@ fn main() -> Result<()> {
 
     println!("starting the inference loop");
     print!("{prompt}");
-    let mut logits_processor = LogitsProcessor::new(args.seed, args.temperature, args.top_p);
+    let mut logits_processor = LogitsProcessor::new(args.seed, Some(args.temperature), args.top_p);
     let start_gen = std::time::Instant::now();
     let mut index_pos = 0;
     let mut token_generated = 0;

candle-transformers/src/models/llama.rs

@@ -16,6 +16,8 @@ pub struct LlamaConfig {
     pub rms_norm_eps: f64,
     #[serde(default = "default_rope")]
     pub rope_theta: f32,
+    pub bos_token_id: Option<u32>,
+    pub eos_token_id: Option<u32>,
 }
 
 fn default_rope() -> f32 {
@@ -34,6 +36,8 @@ impl LlamaConfig {
             rms_norm_eps: self.rms_norm_eps,
             rope_theta: self.rope_theta,
             use_flash_attn,
+            bos_token_id: self.bos_token_id,
+            eos_token_id: self.eos_token_id,
         }
     }
 }
@@ -49,6 +53,8 @@ pub struct Config {
     pub use_flash_attn: bool,
     pub rms_norm_eps: f64,
     pub rope_theta: f32,
+    pub bos_token_id: Option<u32>,
+    pub eos_token_id: Option<u32>,
 }
 
 impl Config {
@@ -63,6 +69,8 @@ impl Config {
             use_flash_attn,
             rms_norm_eps: 1e-6,
             rope_theta: 10_000.0,
+            bos_token_id: None,
+            eos_token_id: None,
         }
     }
 
@@ -77,6 +85,8 @@ impl Config {
             use_flash_attn,
             rms_norm_eps: 1e-5,
             rope_theta: 10_000.0,
+            bos_token_id: None,
+            eos_token_id: None,
         }
     }
 }