llama : optimize memory buffers (#2325)

This commit is contained in:
Georgi Gerganov 2023-07-22 21:17:57 +03:00 committed by GitHub
parent b5fe67f8c6
commit b47b8a9cfe
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3 changed files with 66 additions and 73 deletions

View file

@ -139,17 +139,14 @@ int main(int argc, char ** argv) {
params.n_threads, std::thread::hardware_concurrency(), llama_print_system_info());
}
// determine the maximum memory usage needed to do inference for the given n_batch and n_predict parameters
// determine the maximum memory usage needed to do inference for the given n_batch and n_ctx parameters
// uncomment the "used_mem" line in llama.cpp to see the results
if (params.mem_test) {
{
const std::vector<llama_token> tmp(params.n_batch, llama_token_bos());
llama_eval(ctx, tmp.data(), tmp.size(), 0, params.n_threads);
}
fprintf(stderr, "%s: testing memory usage for n_batch = %d, n_ctx = %d\n", __func__, params.n_batch, params.n_ctx);
{
const std::vector<llama_token> tmp = { 0, };
llama_eval(ctx, tmp.data(), tmp.size(), params.n_predict - 1, params.n_threads);
const std::vector<llama_token> tmp(params.n_batch, llama_token_bos());
llama_eval(ctx, tmp.data(), tmp.size(), params.n_ctx, params.n_threads);
}
llama_print_timings(ctx);

View file

@ -98,18 +98,17 @@ static void ggml_graph_compute_helper(std::vector<uint8_t> & buf, ggml_cgraph *
}
//
// memory sizes
// memory sizes (calculated for n_batch == 512)
//
static const std::map<e_model, size_t> & MEM_REQ_SCRATCH0(int n_ctx)
{
static std::map<e_model, size_t> k_sizes = {
/* empirical scaling, still a guess */
{ MODEL_3B, ((size_t) n_ctx / 16ull + 128ull) * MB },
{ MODEL_7B, ((size_t) n_ctx / 16ull + 256ull) * MB },
{ MODEL_13B, ((size_t) n_ctx / 12ull + 256ull) * MB },
{ MODEL_30B, ((size_t) n_ctx / 10ull + 256ull) * MB },
{ MODEL_65B, ((size_t) n_ctx / 8ull + 512ull) * MB },
{ MODEL_3B, ((size_t) n_ctx / 16ull + 92ull) * MB },
{ MODEL_7B, ((size_t) n_ctx / 16ull + 100ull) * MB },
{ MODEL_13B, ((size_t) n_ctx / 12ull + 120ull) * MB },
{ MODEL_30B, ((size_t) n_ctx / 9ull + 160ull) * MB },
{ MODEL_65B, ((size_t) n_ctx / 6ull + 256ull) * MB }, // guess
};
return k_sizes;
}
@ -117,38 +116,24 @@ static const std::map<e_model, size_t> & MEM_REQ_SCRATCH0(int n_ctx)
static const std::map<e_model, size_t> & MEM_REQ_SCRATCH1()
{
static std::map<e_model, size_t> k_sizes = {
{ MODEL_3B, 256ull * MB },
{ MODEL_7B, 512ull * MB },
{ MODEL_13B, 512ull * MB },
{ MODEL_30B, 512ull * MB },
{ MODEL_65B, 1024ull * MB },
{ MODEL_3B, 128ull * MB },
{ MODEL_7B, 160ull * MB },
{ MODEL_13B, 192ull * MB },
{ MODEL_30B, 256ull * MB },
{ MODEL_65B, 384ull * MB }, // guess
};
return k_sizes;
}
// 2*n_embd*n_ctx*n_layer*sizeof(float16)
static const std::map<e_model, size_t> & MEM_REQ_KV_SELF()
// used to store the compute graph tensors + non-scratch data
static const std::map<e_model, size_t> & MEM_REQ_EVAL()
{
static std::map<e_model, size_t> k_sizes = {
{ MODEL_3B, 682ull * MB },
{ MODEL_7B, 1026ull * MB },
{ MODEL_13B, 1608ull * MB },
{ MODEL_30B, 3124ull * MB },
{ MODEL_65B, 5120ull * MB },
};
return k_sizes;
}
// this is mostly needed for temporary mul_mat buffers to dequantize the data
// not actually needed if BLAS is disabled
static const std::map<e_model, size_t> & MEM_REQ_EVAL(int n_ctx)
{
static std::map<e_model, size_t> k_sizes = {
{ MODEL_3B, ((size_t) n_ctx / 256ull + 512ull) * MB },
{ MODEL_7B, ((size_t) n_ctx / 256ull + 768ull) * MB },
{ MODEL_13B, ((size_t) n_ctx / 256ull + 1024ull) * MB },
{ MODEL_30B, ((size_t) n_ctx / 256ull + 1280ull) * MB },
{ MODEL_65B, ((size_t) n_ctx / 256ull + 1536ull) * MB },
{ MODEL_3B, 8ull * MB },
{ MODEL_7B, 10ull * MB },
{ MODEL_13B, 12ull * MB },
{ MODEL_30B, 16ull * MB },
{ MODEL_65B, 24ull * MB }, // guess
};
return k_sizes;
}
@ -199,6 +184,15 @@ struct llama_hparams {
bool operator!=(const llama_hparams & other) const {
return static_cast<bool>(memcmp(this, &other, sizeof(llama_hparams)));
}
size_t kv_size() const {
size_t result = 2ull;
result *= (size_t) n_embd;
result *= (size_t) n_ctx;
result *= (size_t) n_layer;
result *= sizeof(ggml_fp16_t);
return result;
}
};
struct llama_layer {
@ -1186,11 +1180,11 @@ static void llama_model_load_internal(
mmapped_size - vram_weights + // weights in VRAM not in memory
MEM_REQ_SCRATCH0(hparams.n_ctx).at(model.type) +
MEM_REQ_SCRATCH1().at(model.type) +
MEM_REQ_EVAL(hparams.n_ctx).at(model.type);
MEM_REQ_EVAL().at(model.type);
// this is the memory required by one llama_state
const size_t mem_required_state =
scale*MEM_REQ_KV_SELF().at(model.type);
scale*hparams.kv_size();
fprintf(stderr, "%s: mem required = %7.2f MB (+ %7.2f MB per state)\n", __func__,
mem_required / 1024.0 / 1024.0, mem_required_state / 1024.0 / 1024.0);
@ -1231,7 +1225,7 @@ static void llama_model_load_internal(
fprintf(stderr, "%s: cannot offload v cache to GPU due to low VRAM option\n", __func__);
} else {
fprintf(stderr, "%s: offloading v cache to GPU\n", __func__);
vram_kv_cache += MEM_REQ_KV_SELF().at(model.type) / 2;
vram_kv_cache += hparams.kv_size() / 2;
}
}
if (n_gpu_layers > (int) hparams.n_layer + 2) {
@ -1239,7 +1233,7 @@ static void llama_model_load_internal(
fprintf(stderr, "%s: cannot offload k cache to GPU due to low VRAM option\n", __func__);
} else {
fprintf(stderr, "%s: offloading k cache to GPU\n", __func__);
vram_kv_cache += MEM_REQ_KV_SELF().at(model.type) / 2;
vram_kv_cache += hparams.kv_size() / 2;
}
}
#elif defined(GGML_USE_CLBLAST)
@ -1739,10 +1733,12 @@ static bool llama_eval_internal(
}
#if 0
printf("\n%s: used_mem = %.3f MB, scratch -- %.3f MB %.3f MB\n", __func__,
printf("\n%s: used_mem: eval ctx %.3f MB, scratch %.3f MB %.3f MB, work buf %.3f MB, n_past = %d, N = %d\n", __func__,
ggml_used_mem(ctx0)/1024.0/1024.0,
lctx.get_buf_max_mem(0)/1024.0/1024.0,
lctx.get_buf_max_mem(1)/1024.0/1024.0);
lctx.get_buf_max_mem(1)/1024.0/1024.0,
lctx.work_buffer.size()/1024.0/1024.0,
n_past, N);
#endif
ggml_free(ctx0);
@ -2533,16 +2529,6 @@ static void llama_model_quantize_internal(const std::string & fname_inp, const s
} else {
new_type = quantized_type;
#ifdef GGML_USE_K_QUANTS
bool convert_incompatible_tensor = false;
if (quantized_type == GGML_TYPE_Q2_K || quantized_type == GGML_TYPE_Q3_K || quantized_type == GGML_TYPE_Q4_K ||
quantized_type == GGML_TYPE_Q5_K || quantized_type == GGML_TYPE_Q6_K) {
int nx = tensor.ne.at(0);
int ny = tensor.ne.at(1);
if (nx % QK_K != 0 || ny % QK_K != 0) {
fprintf(stderr, "\n\nTensor sizes %d x %d are not divisible by %d, required for k-quants.\n",nx,ny,QK_K);
convert_incompatible_tensor = true;
}
}
if (tensor.name == "output.weight") {
int nx = tensor.ne.at(0);
int ny = tensor.ne.at(1);
@ -2568,6 +2554,16 @@ static void llama_model_quantize_internal(const std::string & fname_inp, const s
if (ftype == LLAMA_FTYPE_MOSTLY_Q3_K_M || ftype == LLAMA_FTYPE_MOSTLY_Q2_K) new_type = GGML_TYPE_Q4_K;
else if (ftype == LLAMA_FTYPE_MOSTLY_Q3_K_L) new_type = GGML_TYPE_Q5_K;
}
bool convert_incompatible_tensor = false;
if (new_type == GGML_TYPE_Q2_K || new_type == GGML_TYPE_Q3_K || new_type == GGML_TYPE_Q4_K ||
new_type == GGML_TYPE_Q5_K || new_type == GGML_TYPE_Q6_K) {
int nx = tensor.ne.at(0);
int ny = tensor.ne.at(1);
if (nx % QK_K != 0 || ny % QK_K != 0) {
fprintf(stderr, "\n\nTensor sizes %d x %d are not divisible by %d, required for k-quants.\n",nx,ny,QK_K);
convert_incompatible_tensor = true;
}
}
if (convert_incompatible_tensor) {
if (tensor.name == "output.weight") {
new_type = GGML_TYPE_F16; //fall back to F16 instead of just failing.
@ -2594,7 +2590,7 @@ static void llama_model_quantize_internal(const std::string & fname_inp, const s
f32_data = (float *) f32_conv_buf.addr;
}
printf("quantizing .. ");
printf("quantizing to %s .. ", ggml_type_name(new_type));
fflush(stdout);
work.resize(nelements * 4); // upper bound on size
@ -2775,7 +2771,7 @@ struct llama_context * llama_new_context_with_model(
ctx->embedding.resize(hparams.n_embd);
}
ctx->buf_compute.resize(MEM_REQ_EVAL(hparams.n_ctx).at(ctx->model.type));
ctx->buf_compute.resize(MEM_REQ_EVAL().at(ctx->model.type));
ctx->buf_scratch[0].resize(MEM_REQ_SCRATCH0(hparams.n_ctx).at(ctx->model.type));
ctx->buf_scratch[1].resize(MEM_REQ_SCRATCH1().at(ctx->model.type));