diff options
Diffstat (limited to 'examples/quantize-stats')
| -rw-r--r-- | examples/quantize-stats/CMakeLists.txt | 4 | ||||
| -rw-r--r-- | examples/quantize-stats/quantize-stats.cpp | 355 |
2 files changed, 359 insertions, 0 deletions
diff --git a/examples/quantize-stats/CMakeLists.txt b/examples/quantize-stats/CMakeLists.txt new file mode 100644 index 0000000..7bebc11 --- /dev/null +++ b/examples/quantize-stats/CMakeLists.txt @@ -0,0 +1,4 @@ +set(TARGET quantize-stats) +add_executable(${TARGET} quantize-stats.cpp) +target_link_libraries(${TARGET} PRIVATE llama ${CMAKE_THREAD_LIBS_INIT}) +target_compile_features(${TARGET} PRIVATE cxx_std_11) diff --git a/examples/quantize-stats/quantize-stats.cpp b/examples/quantize-stats/quantize-stats.cpp new file mode 100644 index 0000000..af1e627 --- /dev/null +++ b/examples/quantize-stats/quantize-stats.cpp @@ -0,0 +1,355 @@ +#include "ggml.h" +#include "llama.h" + +#include <algorithm> +#include <cassert> +#include <cinttypes> +#include <cmath> +#include <cstdio> +#include <cstring> +#include <map> +#include <numeric> +#include <regex> +#include <string> +#include <unordered_map> +#include <vector> + +static const char * type_strs[] = { "q4_0", "q4_1", "i8", "i16", "i32", "f16", "f32" }; +static_assert(sizeof(type_strs) == GGML_TYPE_COUNT * sizeof(char *), "Incomplete type list"); + +struct quantize_stats_params { + std::string model = "models/7B/ggml-model-f16.bin"; + bool verbose = false; + bool per_layer_stats = false; + bool print_histogram = false; + bool reference = false; + std::vector<std::string> include_layers; + std::vector<std::string> exclude_layers; + std::vector<enum ggml_type> include_types; +}; + +const int64_t SCRATCH_ELEMENTS = 32*32; +const size_t HISTOGRAM_BUCKETS = 150; +const double HISTOGRAM_RANGE = 0.03; + +struct error_stats { + size_t num_samples; + double total_error; + double max_error; + uint64_t error_histogram[HISTOGRAM_BUCKETS]; +}; + + +void quantize_stats_print_usage(int /*argc*/, char ** argv) { + quantize_stats_params params; + fprintf(stderr, "usage: %s [options]\n", argv[0]); + fprintf(stderr, "\n"); + fprintf(stderr, "options:\n"); + fprintf(stderr, " -h, --help show this help message and exit\n"); + fprintf(stderr, " -m FNAME, --model FNAME\n"); + fprintf(stderr, " model path (default: %s)\n", params.model.c_str()); + fprintf(stderr, " -r, --reference\n"); + fprintf(stderr, " use reference implementation (default: false)\n"); + fprintf(stderr, " -v, --verbose\n"); + fprintf(stderr, " verbose output (default: false)\n"); + fprintf(stderr, " -p, --per-layer-stats\n"); + fprintf(stderr, " print stats per layer (default: false)\n"); + fprintf(stderr, " --histogram\n"); + fprintf(stderr, " print error histogram (default: false)\n"); + fprintf(stderr, " -l LAYER, --include-layer LAYER\n"); + fprintf(stderr, " only test layers matching pattern\n"); + fprintf(stderr, " -L LAYER, --exclude-layer LAYER\n"); + fprintf(stderr, " exclude layers matching pattern\n"); + fprintf(stderr, " -t TYPE, --type TYPE\n"); + fprintf(stderr, " only test given type (q4_0, q4_1)\n"); + fprintf(stderr, "\n"); +} + +// Check if a layer is included/excluded by command line +bool layer_included(const quantize_stats_params params, const std::string & layer) { + for (const auto& excluded : params.exclude_layers) { + if (std::regex_search(layer, std::regex(excluded))) { + return false; + } + } + for (const auto& included : params.include_layers) { + if (std::regex_search(layer, std::regex(included))) { + return true; + } + } + return params.include_layers.empty(); +} + +// Update error statistics given vectors with the before/after result of quantization +void update_error_stats(int64_t nelements, const float * input, const float * output, error_stats & stats) { + for (int64_t i = 0; i < nelements; i++) { + double diff = input[i] - output[i]; + stats.total_error += diff * diff; + stats.max_error = fmax(fabs(diff), stats.max_error); + stats.error_histogram[std::max(std::min((size_t) floor(fabs(diff) / HISTOGRAM_RANGE * HISTOGRAM_BUCKETS), HISTOGRAM_BUCKETS-1), (size_t) 0)]++; + } + stats.num_samples += nelements; +} + +double find_quantile(const error_stats & stats, double quantile) { + double sum = std::accumulate(std::begin(stats.error_histogram), std::end(stats.error_histogram), 0.0); + + double accum = 0; + for (size_t i = 0; i < HISTOGRAM_BUCKETS; i++) { + accum += stats.error_histogram[i]; + if (accum >= sum*quantile) { + return (i+1) * HISTOGRAM_RANGE / HISTOGRAM_BUCKETS; + } + } + return INFINITY; +} + +void print_error_stats(const std::string & name, const error_stats & stats, bool print_histogram) { + double rmse = sqrt(stats.total_error / (double) stats.num_samples); + double median = find_quantile(stats, .5); + double pct95 = find_quantile(stats, .95); + printf("%-50s: rmse %.8f, maxerr %.8f, 95pct<%.4f, median<%.4f\n", name.c_str(), rmse, stats.max_error, pct95, median); + if (print_histogram) { + printf("Error distribution:\n"); + for (size_t i = 0; i < HISTOGRAM_BUCKETS; i++) { + double lower = i * HISTOGRAM_RANGE / HISTOGRAM_BUCKETS; + double upper = (i+1) * HISTOGRAM_RANGE / HISTOGRAM_BUCKETS; + if (i == HISTOGRAM_BUCKETS -1) upper = INFINITY; + printf("[%3.4f, %3.4f): %11" PRIu64 "\n", lower, upper, stats.error_histogram[i]); + } + } +} + +// copied from ggml.h - verify that we can access this as a flat array +static bool tensor_is_contiguous(const struct ggml_tensor * tensor) { + static_assert(GGML_MAX_DIMS == 4, "GGML_MAX_DIMS is not 4 - update this function"); + + return + tensor->nb[0] == ggml_type_size(tensor->type) && + tensor->nb[1] == (tensor->nb[0]*tensor->ne[0])/ggml_blck_size(tensor->type) && + tensor->nb[2] == tensor->nb[1]*tensor->ne[1] && + tensor->nb[3] == tensor->nb[2]*tensor->ne[2]; +} + +// Run quantization function for a single layer and update error stats +void test_roundtrip_on_layer( + std::string & name, + bool print_layer_stats, + const quantize_fns_t & qfns, + bool use_reference, + const ggml_tensor * layer, + float * input_scratch, + char *quantized_scratch, + float * output_scratch, + error_stats & total_error) { + + assert(tensor_is_contiguous(layer)); + error_stats layer_error {}; + int64_t nelements = ggml_nelements(layer); + + for (int64_t offset = 0; offset < nelements; offset += SCRATCH_ELEMENTS) { + int64_t chunk_size = std::min(SCRATCH_ELEMENTS, nelements - offset); + + if (layer->type == GGML_TYPE_F16) { + for (int i = 0; i < chunk_size; i++) { + input_scratch[i] = ggml_get_f32_1d(layer, i + offset); + } + } else { + input_scratch = ggml_get_data_f32(layer) + offset; + } + + if (use_reference) { + qfns.quantize_row_q_reference(input_scratch, quantized_scratch, chunk_size); + } else { + qfns.quantize_row_q(input_scratch, quantized_scratch, chunk_size); + } + qfns.dequantize_row_q(quantized_scratch, output_scratch, chunk_size); + + update_error_stats(chunk_size, input_scratch, output_scratch, total_error); + if (print_layer_stats) { + update_error_stats(chunk_size, input_scratch, output_scratch, layer_error); + } + } + if (print_layer_stats) { + print_error_stats(name, layer_error, false); + } +} + +int main(int argc, char ** argv) { + ggml_time_init(); + + quantize_stats_params params; + + // read command line + + bool invalid_param = false; + std::string arg; + for (int i = 1; i < argc; i++) { + arg = argv[i]; + + if (arg == "-h" || arg == "--help") { + quantize_stats_print_usage(argc, argv); + exit(0); + } else if (arg == "-r" || arg == "--reference") { + params.reference = true; + } else if (arg == "-v") { + params.verbose = true; + } else if (arg == "-p" || arg == "--per-layer-stats") { + params.per_layer_stats = true; + } else if (arg == "--histogram") { + params.print_histogram = true; + } else if (arg == "-m" || arg == "--model") { + if (++i >= argc) { + invalid_param = true; + break; + } + params.model = argv[i]; + } else if (arg == "-l" || arg == "--include-layer") { + if (++i >= argc) { + invalid_param = true; + break; + } + params.include_layers.push_back(argv[i]); + } else if (arg == "-L" || arg == "--exclude-layer") { + if (++i >= argc) { + invalid_param = true; + break; + } + params.exclude_layers.push_back(argv[i]); + } else if (arg == "-t" || arg == "--type") { + if (++i >= argc) { + invalid_param = true; + break; + } + int j; + for (j = 0; j < GGML_TYPE_COUNT && strcmp(argv[i], type_strs[j]) != 0; j++) { + // find match + } + if (j < GGML_TYPE_COUNT) { + params.include_types.push_back((ggml_type) j); + } else { + fprintf(stderr, "error: %s not in list of types\n", argv[i]); + invalid_param = true; + } + } else { + fprintf(stderr, "error: unknown argument: %s\n", arg.c_str()); + quantize_stats_print_usage(argc, argv); + return 1; + } + } + if (invalid_param) { + fprintf(stderr, "error: invalid parameter for argument: %s\n", arg.c_str()); + quantize_stats_print_usage(argc, argv); + return 1; + } + + // load the model + fprintf(stderr, "Loading model\n"); + + const int64_t t_main_start_us = ggml_time_us(); + llama_context * ctx; + + { + auto lparams = llama_context_default_params(); + + lparams.n_ctx = 256; + lparams.n_parts = 1; + lparams.seed = 1; + lparams.f16_kv = false; + lparams.use_mlock = false; + + ctx = llama_init_from_file(params.model.c_str(), lparams); + + if (ctx == NULL) { + fprintf(stderr, "%s: error: failed to load model '%s'\n", __func__, params.model.c_str()); + return 1; + } + } + + // Sort tensors for consistent output + const auto tensors = llama_internal_get_tensor_map(ctx); + std::map<std::string, struct ggml_tensor *> tensors_sorted { tensors.begin(), tensors.end() }; + + // check layer tensors + int included_layers = 0; + int64_t max_nelements = 0; + bool is_f16 = false; + for (const auto& kv_tensor : tensors_sorted) { + if (!layer_included(params, kv_tensor.first)) { + continue; + } + if (params.verbose) { + printf("%s: type %s, size %" PRId64 "\n", kv_tensor.first.c_str(), type_strs[kv_tensor.second->type], ggml_nelements(kv_tensor.second)); + } + if (kv_tensor.second->type == GGML_TYPE_F16) { + is_f16 = true; + } else if (kv_tensor.second->type != GGML_TYPE_F32) { + fprintf(stderr, "%s: error: Quantization should be tested with a float model, " + "this model contains already quantized layers (%s is type %d)\n", __func__, kv_tensor.first.c_str(), kv_tensor.second->type); + llama_free(ctx); + return 1; + } + included_layers++; + max_nelements = std::max(max_nelements, ggml_nelements(kv_tensor.second)); + } + + if (is_f16) { + printf("note: source model is f16\n"); + } + printf("testing %d layers with max size %" PRId64 "\n", included_layers, max_nelements); + // allocate scratch space + std::vector<float> input_scratch(SCRATCH_ELEMENTS); + std::vector<char> quantized_scratch(SCRATCH_ELEMENTS*4); + std::vector<float> output_scratch(SCRATCH_ELEMENTS); + + // loop throught quantization types + for (int i = 0; i < GGML_TYPE_COUNT; i++) { + if (!params.include_types.empty() && std::find(params.include_types.begin(), params.include_types.end(), i) == params.include_types.end()) { + continue; + } + quantize_fns_t qfns = ggml_internal_get_quantize_fn(i); + if (qfns.quantize_row_q && qfns.dequantize_row_q) { + if (params.verbose) { + printf("testing %s ...\n", type_strs[i]); + } + + error_stats global_stats {}; + + for (const auto& kv_tensor : tensors_sorted) { + if (!layer_included(params, kv_tensor.first)) { + continue; + } + if (params.verbose) { + printf(" %s ...\n", kv_tensor.first.c_str()); + } + std::string layer_name { type_strs[i] }; + layer_name += "::" + kv_tensor.first; + test_roundtrip_on_layer( + layer_name, + params.per_layer_stats, + qfns, + params.reference, + kv_tensor.second, + input_scratch.data(), + quantized_scratch.data(), + output_scratch.data(), + global_stats + ); + } + + print_error_stats(type_strs[i], global_stats, params.print_histogram); + } + } + + + llama_free(ctx); + // report timing + { + const int64_t t_main_end_us = ggml_time_us(); + + printf("\n"); + printf("%s: total time = %8.2f ms\n", __func__, (t_main_end_us - t_main_start_us)/1000.0); + } + + return 0; +} |