ggml : GPU-accelerated token generation (#1412)

* CUDA kernel for q4_0 dequant. + mat. vec. mult.

* Added q4_1 via template

* Added missing __syncthreads();

* --gpu_layers -> --gpu-layers

* Shorter dequantize_mul_mat_vec line

* q5_0 dequantize_mul_mat kernel

* More readable dequantize_mul_mat_vec logic

* dequantize_mul_mat_vec kernels for q5_1, q8_0, f16

* llama : offload "output" tensor to GPU too + coding style fixes

---------

Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>

examples/common.cpp

@@ -277,6 +277,12 @@ bool gpt_params_parse(int argc, char ** argv, gpt_params & params) {
             params.use_color = true;
         } else if (arg == "--mlock") {
             params.use_mlock = true;
+        } else if (arg == "--gpu-layers" || arg == "-ngl" || arg == "--n-gpu-layers") {
+            if (++i >= argc) {
+                invalid_param = true;
+                break;
+            }
+            params.n_gpu_layers = std::stoi(argv[i]);
         } else if (arg == "--no-mmap") {
             params.use_mmap = false;
         } else if (arg == "--mtest") {
@@ -421,6 +427,8 @@ void gpt_print_usage(int /*argc*/, char ** argv, const gpt_params & params) {
     if (llama_mmap_supported()) {
         fprintf(stderr, "  --no-mmap             do not memory-map model (slower load but may reduce pageouts if not using mlock)\n");
     }
+    fprintf(stderr, "  -ngl N, --n-gpu-layers N\n");
+    fprintf(stderr, "                        number of layers to store in VRAM\n");
     fprintf(stderr, "  --mtest               compute maximum memory usage\n");
     fprintf(stderr, "  --verbose-prompt      print prompt before generation\n");
     fprintf(stderr, "  --lora FNAME          apply LoRA adapter (implies --no-mmap)\n");
@@ -463,14 +471,15 @@ std::vector<llama_token> llama_tokenize(struct llama_context * ctx, const std::s
 struct llama_context * llama_init_from_gpt_params(const gpt_params & params) {
     auto lparams = llama_context_default_params();
 
-    lparams.n_ctx      = params.n_ctx;
-    lparams.n_parts    = params.n_parts;
-    lparams.seed       = params.seed;
-    lparams.f16_kv     = params.memory_f16;
-    lparams.use_mmap   = params.use_mmap;
-    lparams.use_mlock  = params.use_mlock;
-    lparams.logits_all = params.perplexity;
-    lparams.embedding  = params.embedding;
+    lparams.n_ctx        = params.n_ctx;
+    lparams.n_parts      = params.n_parts;
+    lparams.n_gpu_layers = params.n_gpu_layers;
+    lparams.seed         = params.seed;
+    lparams.f16_kv       = params.memory_f16;
+    lparams.use_mmap     = params.use_mmap;
+    lparams.use_mlock    = params.use_mlock;
+    lparams.logits_all   = params.perplexity;
+    lparams.embedding    = params.embedding;
 
     llama_context * lctx = llama_init_from_file(params.model.c_str(), lparams);
 

examples/common.h

@@ -21,13 +21,14 @@
 int32_t get_num_physical_cores();
 
 struct gpt_params {
-    int32_t seed          = -1;   // RNG seed
+    int32_t seed          = -1;  // RNG seed
     int32_t n_threads     = get_num_physical_cores();
     int32_t n_predict     = -1;  // new tokens to predict
-    int32_t n_parts       = -1;   // amount of model parts (-1 = determine from model dimensions)
-    int32_t n_ctx         = 512;  // context size
-    int32_t n_batch       = 512;  // batch size for prompt processing (must be >=32 to use BLAS)
-    int32_t n_keep        = 0;    // number of tokens to keep from initial prompt
+    int32_t n_parts       = -1;  // amount of model parts (-1 = determine from model dimensions)
+    int32_t n_ctx         = 512; // context size
+    int32_t n_batch       = 512; // batch size for prompt processing (must be >=32 to use BLAS)
+    int32_t n_keep        = 0;   // number of tokens to keep from initial prompt
+    int32_t n_gpu_layers  = 0;   // number of layers to store in VRAM
 
     // sampling parameters
     std::unordered_map<llama_token, float> logit_bias; // logit bias for specific tokens