From 026d2ad47247c006bd9ef6e583d76b6ab69875b6 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Johannes=20G=C3=A4=C3=9Fler?= Date: Sat, 27 Dec 2025 20:18:35 +0100 Subject: [PATCH] llama: fix magic number of 999 for GPU layers (#18266) * llama: fix magic number of 999 for GPU layers * use strings for -ngl, -ngld * enacapsulate n_gpu_layers, split_mode --- common/arg.cpp | 27 +++++++++++++++++++++------ common/common.cpp | 5 +---- common/common.h | 2 +- include/llama.h | 7 ++++--- src/llama-context.cpp | 6 +++--- src/llama-model.cpp | 14 +++++++++++--- src/llama-model.h | 7 +++++-- 7 files changed, 46 insertions(+), 22 deletions(-) diff --git a/common/arg.cpp b/common/arg.cpp index 774f8731a9..189470182a 100644 --- a/common/arg.cpp +++ b/common/arg.cpp @@ -2137,11 +2137,18 @@ common_params_context common_params_parser_init(common_params & params, llama_ex } } ).set_examples({LLAMA_EXAMPLE_SPECULATIVE, LLAMA_EXAMPLE_SERVER, LLAMA_EXAMPLE_CLI}).set_env("LLAMA_ARG_N_CPU_MOE_DRAFT")); + GGML_ASSERT(params.n_gpu_layers < 0); // string_format would need to be extended for a default >= 0 add_opt(common_arg( {"-ngl", "--gpu-layers", "--n-gpu-layers"}, "N", - string_format("max. number of layers to store in VRAM (default: %d)", params.n_gpu_layers), - [](common_params & params, int value) { - params.n_gpu_layers = value; + string_format("max. number of layers to store in VRAM, either an exact number, 'auto', or 'all' (default: %s)", params.n_gpu_layers == -1 ? "auto" : "all"), + [](common_params & params, const std::string & value) { + if (value == "auto") { + params.n_gpu_layers = -1; + } else if (value == "all") { + params.n_gpu_layers = -2; + } else { + params.n_gpu_layers = std::stoi(value); + } if (!llama_supports_gpu_offload()) { fprintf(stderr, "warning: no usable GPU found, --gpu-layers option will be ignored\n"); fprintf(stderr, "warning: one possible reason is that llama.cpp was compiled without GPU support\n"); @@ -3175,11 +3182,19 @@ common_params_context common_params_parser_init(common_params & params, llama_ex params.speculative.devices = parse_device_list(value); } ).set_examples({LLAMA_EXAMPLE_SPECULATIVE, LLAMA_EXAMPLE_SERVER, LLAMA_EXAMPLE_CLI})); + GGML_ASSERT(params.speculative.n_gpu_layers < 0); // string_format would need to be extended for a default >= 0 add_opt(common_arg( {"-ngld", "--gpu-layers-draft", "--n-gpu-layers-draft"}, "N", - "number of layers to store in VRAM for the draft model", - [](common_params & params, int value) { - params.speculative.n_gpu_layers = value; + string_format("max. number of draft model layers to store in VRAM, either an exact number, 'auto', or 'all' (default: %s)", + params.speculative.n_gpu_layers == -1 ? "auto" : "all"), + [](common_params & params, const std::string & value) { + if (value == "auto") { + params.speculative.n_gpu_layers = -1; + } else if (value == "all") { + params.speculative.n_gpu_layers = -2; + } else { + params.speculative.n_gpu_layers = std::stoi(value); + } if (!llama_supports_gpu_offload()) { fprintf(stderr, "warning: no usable GPU found, --gpu-layers-draft option will be ignored\n"); fprintf(stderr, "warning: one possible reason is that llama.cpp was compiled without GPU support\n"); diff --git a/common/common.cpp b/common/common.cpp index acf2ec841d..8d62893370 100644 --- a/common/common.cpp +++ b/common/common.cpp @@ -1341,10 +1341,7 @@ struct llama_model_params common_model_params_to_llama(common_params & params) { mparams.devices = params.devices.data(); } - if (params.n_gpu_layers != -1) { - mparams.n_gpu_layers = params.n_gpu_layers; - } - + mparams.n_gpu_layers = params.n_gpu_layers; mparams.main_gpu = params.main_gpu; mparams.split_mode = params.split_mode; mparams.tensor_split = params.tensor_split; diff --git a/common/common.h b/common/common.h index 334372073a..f8bc686b6f 100644 --- a/common/common.h +++ b/common/common.h @@ -329,7 +329,7 @@ struct common_params { // offload params std::vector devices; // devices to use for offloading - int32_t n_gpu_layers = -1; // number of layers to store in VRAM (-1 - use default) + int32_t n_gpu_layers = -1; // number of layers to store in VRAM, -1 is auto, <= -2 is all int32_t main_gpu = 0; // the GPU that is used for scratch and small tensors float tensor_split[128] = {0}; // how split tensors should be distributed across GPUs bool fit_params = true; // whether to fit unset model/context parameters to free device memory diff --git a/include/llama.h b/include/llama.h index 2d4e9a94e2..4f0124fdc8 100644 --- a/include/llama.h +++ b/include/llama.h @@ -286,7 +286,7 @@ extern "C" { // NULL-terminated list of buffer types to use for tensors that match a pattern const struct llama_model_tensor_buft_override * tensor_buft_overrides; - int32_t n_gpu_layers; // number of layers to store in VRAM + int32_t n_gpu_layers; // number of layers to store in VRAM, a negative value means all layers enum llama_split_mode split_mode; // how to split the model across multiple GPUs // the GPU that is used for the entire model when split_mode is LLAMA_SPLIT_MODE_NONE @@ -474,8 +474,9 @@ extern "C" { }; // fits mparams and cparams to free device memory (assumes system memory is unlimited) - // returns true if the parameters could be successfully modified to fit device memory - // this function is NOT thread safe because it modifies the global llama logger state + // - returns true if the parameters could be successfully modified to fit device memory + // - this function is NOT thread safe because it modifies the global llama logger state + // - only parameters that have the same value as in llama_default_model_params are modified LLAMA_API enum llama_params_fit_status llama_params_fit( const char * path_model, struct llama_model_params * mparams, diff --git a/src/llama-context.cpp b/src/llama-context.cpp index 015ebae71d..1c530fdc91 100644 --- a/src/llama-context.cpp +++ b/src/llama-context.cpp @@ -294,8 +294,8 @@ llama_context::llama_context( // enabling pipeline parallelism in the scheduler increases memory usage, so it is only done when necessary bool pipeline_parallel = model.n_devices() > 1 && - model.params.n_gpu_layers > (int) model.hparams.n_layer && - model.params.split_mode == LLAMA_SPLIT_MODE_LAYER && + model.n_gpu_layers() > model.hparams.n_layer && + model.split_mode() == LLAMA_SPLIT_MODE_LAYER && cparams.offload_kqv && !model.has_tensor_overrides(); @@ -1570,7 +1570,7 @@ llm_graph_cb llama_context::graph_get_cb() const { // norm may be automatically assigned to the backend of the previous layer, increasing data transfer between backends // FIXME: fix in ggml_backend_sched - const bool full_offload = model.params.n_gpu_layers > (int) model.hparams.n_layer; + const bool full_offload = model.n_gpu_layers() > model.hparams.n_layer; if (ubatch.n_tokens < 32 || full_offload) { if (il != -1 && strcmp(name, "norm") == 0) { const auto & dev_layer = model.dev_layer(il); diff --git a/src/llama-model.cpp b/src/llama-model.cpp index 69075742c9..1d6134ec05 100644 --- a/src/llama-model.cpp +++ b/src/llama-model.cpp @@ -2378,11 +2378,11 @@ void llama_model::load_vocab(llama_model_loader & ml) { bool llama_model::load_tensors(llama_model_loader & ml) { const auto & split_mode = params.split_mode; - const auto & n_gpu_layers = params.n_gpu_layers; const auto & use_mlock = params.use_mlock; const auto & tensor_split = params.tensor_split; - const int n_layer = hparams.n_layer; + const int n_layer = hparams.n_layer; + const int n_gpu_layers = this->n_gpu_layers(); const bool use_mmap_buffer = true; @@ -6884,6 +6884,14 @@ size_t llama_model::n_devices() const { return devices.size(); } +uint32_t llama_model::n_gpu_layers() const { + return params.n_gpu_layers >= 0 ? params.n_gpu_layers : hparams.n_layer + 1; +} + +llama_split_mode llama_model::split_mode() const { + return params.split_mode; +} + std::map llama_model::memory_breakdown() const { std::map ret; for (const auto & [ctx, bufs] : pimpl->ctxs_bufs) { @@ -7794,7 +7802,7 @@ llama_model_params llama_model_default_params() { llama_model_params result = { /*.devices =*/ nullptr, /*.tensor_buft_overrides =*/ nullptr, - /*.n_gpu_layers =*/ 999, + /*.n_gpu_layers =*/ -1, /*.split_mode =*/ LLAMA_SPLIT_MODE_LAYER, /*.main_gpu =*/ 0, /*.tensor_split =*/ nullptr, diff --git a/src/llama-model.h b/src/llama-model.h index 9c00eec75f..dbe5edc153 100644 --- a/src/llama-model.h +++ b/src/llama-model.h @@ -466,8 +466,6 @@ struct llama_model { struct ggml_tensor * dense_2_out_layers = nullptr; struct ggml_tensor * dense_3_out_layers = nullptr; - llama_model_params params; - // gguf metadata std::unordered_map gguf_kv; @@ -498,6 +496,9 @@ struct llama_model { size_t n_tensors() const; size_t n_devices() const; + uint32_t n_gpu_layers() const; + llama_split_mode split_mode() const; + std::map memory_breakdown() const; // total number of parameters in the model @@ -526,6 +527,8 @@ struct llama_model { ggml_cgraph * build_graph(const llm_graph_params & params) const; private: + llama_model_params params; + struct impl; std::unique_ptr pimpl; };