2-bit quantizations (#4897)

* imatrix: load

* imatrix: WIP

* imatrix: Add Q2_K quantization

* imatrix: also guard against Q2_K_S quantization without importance matrix

* imatrix: guard even more against low-bit quantization misuse

---------

Co-authored-by: Iwan Kawrakow <iwan.kawrakow@gmail.com>
This commit is contained in:
Kawrakow 2024-01-14 09:45:56 +02:00 committed by GitHub
parent 807179ec58
commit 147b17ac94
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GPG key ID: 4AEE18F83AFDEB23
9 changed files with 1149 additions and 82 deletions

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@ -8429,9 +8429,23 @@ static ggml_type get_k_quant_type(quantize_state_internal & qs, ggml_type new_ty
if (arch == LLM_ARCH_FALCON || nx % QK_K != 0) {
new_type = GGML_TYPE_Q8_0;
}
else if (ftype == LLAMA_FTYPE_MOSTLY_IQ2_XXS || ftype == LLAMA_FTYPE_MOSTLY_IQ2_XS) {
new_type = GGML_TYPE_Q5_K;
}
else if (new_type != GGML_TYPE_Q8_0) {
new_type = GGML_TYPE_Q6_K;
}
} else if (ftype == LLAMA_FTYPE_MOSTLY_IQ2_XXS || ftype == LLAMA_FTYPE_MOSTLY_IQ2_XS) {
if (name.find("attn_v.weight") != std::string::npos) {
if (qs.model.hparams.n_gqa() >= 4 || qs.model.hparams.n_expert >= 4) new_type = GGML_TYPE_Q4_K;
else new_type = GGML_TYPE_Q2_K;
++qs.i_attention_wv;
}
else if (name.find("ffn_down") != std::string::npos) {
if (qs.i_feed_forward_w2 < qs.n_feed_forward_w2/8) new_type = GGML_TYPE_Q2_K;
++qs.i_feed_forward_w2;
}
else if (name == "token_embd.weight") new_type = GGML_TYPE_Q2_K;
} else if (name.find("attn_v.weight") != std::string::npos) {
if (ftype == LLAMA_FTYPE_MOSTLY_Q2_K) new_type = GGML_TYPE_Q3_K;
else if (ftype == LLAMA_FTYPE_MOSTLY_Q3_K_M) {
@ -8601,6 +8615,13 @@ static void llama_model_quantize_internal(const std::string & fname_inp, const s
if (params->only_copy) {
ftype = model.ftype;
}
const std::unordered_map<std::string, std::vector<float>> * imatrix_data = nullptr;
if (params->imatrix) {
imatrix_data = static_cast<const std::unordered_map<std::string, std::vector<float>>*>(params->imatrix);
if (imatrix_data) {
printf("================================ Have weights data with %d entries\n",int(imatrix_data->size()));
}
}
const size_t align = GGUF_DEFAULT_ALIGNMENT;
struct gguf_context * ctx_out = gguf_init_empty();
@ -8658,6 +8679,8 @@ static void llama_model_quantize_internal(const std::string & fname_inp, const s
// placeholder for the meta data
::zeros(fout, meta_size);
std::set<ggml_type> used_iq2;
for (int i = 0; i < ml.n_tensors; ++i) {
struct ggml_tensor * tensor = ml.get_tensor_meta(i);
@ -8710,6 +8733,35 @@ static void llama_model_quantize_internal(const std::string & fname_inp, const s
} else {
const size_t nelements = ggml_nelements(tensor);
if ((new_type == GGML_TYPE_IQ2_XXS || new_type == GGML_TYPE_IQ2_XS) && used_iq2.find(new_type) == used_iq2.end()) {
ggml_init_iq2_quantization(new_type);
used_iq2.insert(new_type);
}
const float * imatrix = nullptr;
if (imatrix_data) {
auto it = imatrix_data->find(tensor->name);
if (it == imatrix_data->end()) {
printf("\n====== %s: did not find weights for %s\n", __func__, tensor->name);
} else {
if (it->second.size() == (size_t)tensor->ne[0]) {
imatrix = it->second.data();
} else {
printf("\n====== %s: imatrix size %d is different from tensor size %d for %s\n", __func__,
int(it->second.size()), int(tensor->ne[0]), tensor->name);
}
}
}
if ((new_type == GGML_TYPE_IQ2_XXS ||
new_type == GGML_TYPE_IQ2_XS ||
(new_type == GGML_TYPE_Q2_K && params->ftype == LLAMA_FTYPE_MOSTLY_Q2_K_S && strcmp(tensor->name, "token_embd.weight") != 0)) && !imatrix) {
fprintf(stderr, "\n\n============================================================\n");
fprintf(stderr, "Missing importance matrix for tensor %s in a very low-bit quantization\n", tensor->name);
fprintf(stderr, "The result will be garbage, so bailing out\n");
fprintf(stderr, "============================================================\n\n");
throw std::runtime_error(format("Missing importance matrix for tensor %s in a very low-bit quantization", tensor->name));
}
float * f32_data;
if (tensor->type == GGML_TYPE_F32) {
@ -8730,21 +8782,28 @@ static void llama_model_quantize_internal(const std::string & fname_inp, const s
new_data = work.data();
std::array<int64_t, 1 << 4> hist_cur = {};
static const int chunk_size = 32 * 512;
const int n_per_row = tensor->ne[0];
const int nrows = nelements / n_per_row;
static const int min_chunk_size = 32 * 512;
const int chunk_size = n_per_row >= min_chunk_size ? n_per_row : n_per_row * ((min_chunk_size + n_per_row - 1)/n_per_row);
const int nchunk = (nelements + chunk_size - 1)/chunk_size;
const int nthread_use = nthread > 1 ? std::max(1, std::min(nthread, nchunk)) : 1;
if (nthread_use < 2) {
new_size = ggml_quantize_chunk(new_type, f32_data, new_data, 0, nelements, hist_cur.data());
new_size = ggml_quantize_chunk(new_type, f32_data, new_data, 0, nrows, n_per_row, hist_cur.data(), imatrix);
} else {
size_t counter = 0;
int counter = 0;
new_size = 0;
auto compute = [&mutex, &counter, &hist_cur, &new_size, new_type, f32_data, new_data, nelements]() {
auto compute = [&mutex, &counter, &hist_cur, &new_size, new_type, f32_data, new_data, chunk_size,
nrows, n_per_row, imatrix]() {
std::array<int64_t, 1 << 4> local_hist = {};
const int nrows_per_chunk = chunk_size / n_per_row;
size_t local_size = 0;
while (true) {
std::unique_lock<std::mutex> lock(mutex);
size_t first = counter; counter += chunk_size;
if (first >= nelements) {
int first_row = counter; counter += nrows_per_chunk;
if (first_row >= nrows) {
if (local_size > 0) {
for (int j=0; j<int(local_hist.size()); ++j) {
hist_cur[j] += local_hist[j];
@ -8754,8 +8813,9 @@ static void llama_model_quantize_internal(const std::string & fname_inp, const s
break;
}
lock.unlock();
size_t last = std::min(nelements, first + chunk_size);
local_size += ggml_quantize_chunk(new_type, f32_data, new_data, first, last - first, local_hist.data());
const int this_nrow = std::min(nrows - first_row, nrows_per_chunk);
local_size += ggml_quantize_chunk(new_type, f32_data, new_data,
first_row * n_per_row, this_nrow, n_per_row, local_hist.data(), imatrix);
}
};
for (int it = 0; it < nthread_use - 1; ++it) {
@ -8766,7 +8826,7 @@ static void llama_model_quantize_internal(const std::string & fname_inp, const s
workers.clear();
}
LLAMA_LOG_INFO("size = %8.2f MiB -> %8.2f MiB | hist: ", ggml_nbytes(tensor)/1024.0/1024.0, new_size/1024.0/1024.0);
LLAMA_LOG_INFO("size = %8.2f MiB -> %8.2f MiB", ggml_nbytes(tensor)/1024.0/1024.0, new_size/1024.0/1024.0);
int64_t tot_count = 0;
for (size_t i = 0; i < hist_cur.size(); i++) {
hist_all[i] += hist_cur[i];
@ -8774,6 +8834,7 @@ static void llama_model_quantize_internal(const std::string & fname_inp, const s
}
if (tot_count > 0) {
LLAMA_LOG_INFO(" | hist: ");
for (size_t i = 0; i < hist_cur.size(); i++) {
LLAMA_LOG_INFO("%5.3f ", hist_cur[i] / float(nelements));
}
@ -8802,6 +8863,10 @@ static void llama_model_quantize_internal(const std::string & fname_inp, const s
fout.close();
for (auto type : used_iq2) {
ggml_deinit_iq2_quantization(type);
}
gguf_free(ctx_out);
LLAMA_LOG_INFO("%s: model size = %8.2f MB\n", __func__, total_size_org/1024.0/1024.0);
@ -9166,6 +9231,7 @@ struct llama_model_quantize_params llama_model_quantize_default_params() {
/*.quantize_output_tensor =*/ true,
/*.only_copy =*/ false,
/*.pure =*/ false,
/*.imatrix =*/ nullptr,
};
return result;