feat: add ggml fp16 / q8_0 files (#407)

* feat: add ggml fp16 / q8_0 files

* add q8_0.gguf to optional download files

* add download options to split ctranslate2 files and ggml files

crates/tabby-common/src/path.rs

@@ -86,7 +86,7 @@ impl ModelDir {
         self.path_string("ctranslate2")
     }
 
-    pub fn ggml_model_file(&self) -> String {
-        self.path_string("ggml/default.gguf")
+    pub fn ggml_q8_0_file(&self) -> String {
+        self.path_string("ggml/q8_0.gguf")
     }
 }

crates/tabby-download/src/lib.rs

@@ -57,7 +57,12 @@ impl CacheInfo {
     }
 }
 
-pub async fn download_model(model_id: &str, prefer_local_file: bool) -> Result<()> {
+pub async fn download_model(
+    model_id: &str,
+    download_ctranslate2_files: bool,
+    download_ggml_files: bool,
+    prefer_local_file: bool,
+) -> Result<()> {
     if fs::metadata(model_id).is_ok() {
         // Local path, no need for downloading.
         return Ok(());
@@ -67,12 +72,18 @@ pub async fn download_model(model_id: &str, prefer_local_file: bool) -> Result<(
 
     let mut cache_info = CacheInfo::from(model_id).await;
 
-    let optional_files = vec![
-        "ctranslate2/vocabulary.txt",
-        "ctranslate2/shared_vocabulary.txt",
-        "ctranslate2/vocabulary.json",
-        "ctranslate2/shared_vocabulary.json",
-    ];
+    let mut optional_files = vec![];
+    if download_ctranslate2_files {
+        optional_files.push("ctranslate2/vocabulary.txt");
+        optional_files.push("ctranslate2/shared_vocabulary.txt");
+        optional_files.push("ctranslate2/vocabulary.json");
+        optional_files.push("ctranslate2/shared_vocabulary.json");
+    }
+
+    if download_ggml_files {
+        optional_files.push("ggml/q8_0.gguf");
+    }
+
     for path in optional_files {
         cache_info
             .download(
@@ -84,12 +95,13 @@ pub async fn download_model(model_id: &str, prefer_local_file: bool) -> Result<(
             .await?;
     }
 
-    let required_files = vec![
-        "tabby.json",
-        "tokenizer.json",
-        "ctranslate2/config.json",
-        "ctranslate2/model.bin",
-    ];
+    let mut required_files = vec!["tabby.json", "tokenizer.json"];
+
+    if download_ctranslate2_files {
+        required_files.push("ctranslate2/config.json");
+        required_files.push("ctranslate2/model.bin");
+    }
+
     for path in required_files {
         cache_info
             .download(

crates/tabby/src/download.rs

@@ -15,14 +15,19 @@ pub struct DownloadArgs {
 }
 
 pub async fn main(args: &DownloadArgs) {
-    tabby_download::download_model(&args.model, args.prefer_local_file)
-        .await
-        .unwrap_or_else(|err| {
-            fatal!(
-                "Failed to fetch model due to '{}', is '{}' a valid model id?",
-                err,
-                args.model
-            )
-        });
+    tabby_download::download_model(
+        &args.model,
+        /* download_ctranslate2_files= */ true,
+        /* download_ggml_files= */ true,
+        args.prefer_local_file,
+    )
+    .await
+    .unwrap_or_else(|err| {
+        fatal!(
+            "Failed to fetch model due to '{}', is '{}' a valid model id?",
+            err,
+            args.model
+        )
+    });
     info!("model '{}' is ready", args.model);
 }

crates/tabby/src/serve/completions.rs

@@ -186,7 +186,7 @@ fn create_ctranslate2_engine(
 #[cfg(all(target_os = "macos", target_arch = "aarch64"))]
 fn create_llama_engine(model_dir: &ModelDir) -> Box<dyn TextGeneration> {
     let options = llama_cpp_bindings::LlamaEngineOptionsBuilder::default()
-        .model_path(model_dir.ggml_model_file())
+        .model_path(model_dir.ggml_q8_0_file())
         .tokenizer_path(model_dir.tokenizer_file())
         .build()
         .unwrap();

crates/tabby/src/serve/mod.rs

@@ -116,19 +116,35 @@ pub struct ServeArgs {
     compute_type: ComputeType,
 }
 
+#[cfg(not(all(target_os = "macos", target_arch = "aarch64")))]
+fn should_download_ggml_files(device: &Device) -> bool {
+    false
+}
+
+#[cfg(all(target_os = "macos", target_arch = "aarch64"))]
+fn should_download_ggml_files(device: &Device) -> bool {
+    *device == Device::Metal
+}
+
 pub async fn main(config: &Config, args: &ServeArgs) {
     valid_args(args);
 
     // Ensure model exists.
-    tabby_download::download_model(&args.model, true)
-        .await
-        .unwrap_or_else(|err| {
-            fatal!(
-                "Failed to fetch model due to '{}', is '{}' a valid model id?",
-                err,
-                args.model
-            )
-        });
+    tabby_download::download_model(
+        &args.model,
+        /* download_ctranslate2_files= */
+        !should_download_ggml_files(&args.device),
+        /* download_ggml_files= */ should_download_ggml_files(&args.device),
+        /* prefer_local_file= */ true,
+    )
+    .await
+    .unwrap_or_else(|err| {
+        fatal!(
+            "Failed to fetch model due to '{}', is '{}' a valid model id?",
+            err,
+            args.model
+        )
+    });
 
     info!("Starting server, this might takes a few minutes...");
     let app = Router::new()