llama.cpp/examples/perplexity/perplexity.cpp
2024-02-18 22:39:30 +02:00

1860 lines
69 KiB
C++

#include "common.h"
#include "llama.h"
#include <cmath>
#include <cstdio>
#include <cstring>
#include <ctime>
#include <sstream>
#include <thread>
#include <mutex>
#include <atomic>
#include <vector>
#include <array>
#include <fstream>
#include <sstream>
#if defined(_MSC_VER)
#pragma warning(disable: 4244 4267) // possible loss of data
#endif
struct results_perplexity {
std::vector<llama_token> tokens;
double ppl_value;
std::vector<float> logits;
std::vector<float> probs;
};
struct results_log_softmax {
double log_softmax;
float logit;
float prob;
};
static void write_logfile(
const llama_context * ctx, const gpt_params & params, const llama_model * model,
const struct results_perplexity & results
) {
if (params.logdir.empty()) {
return;
}
if (params.hellaswag) {
fprintf(stderr, "%s: warning: logging results is not implemented for HellaSwag. No files will be written.\n", __func__);
return;
}
const std::string timestamp = get_sortable_timestamp();
const bool success = create_directory_with_parents(params.logdir);
if (!success) {
fprintf(stderr, "%s: warning: failed to create logdir %s, cannot write logfile\n",
__func__, params.logdir.c_str());
return;
}
const std::string logfile_path = params.logdir + timestamp + ".yml";
FILE * logfile = fopen(logfile_path.c_str(), "w");
if (logfile == NULL) {
fprintf(stderr, "%s: failed to open logfile %s\n", __func__, logfile_path.c_str());
return;
}
fprintf(logfile, "binary: main\n");
char model_desc[128];
llama_model_desc(model, model_desc, sizeof(model_desc));
dump_non_result_info_yaml(logfile, params, ctx, timestamp, results.tokens, model_desc);
fprintf(logfile, "\n");
fprintf(logfile, "######################\n");
fprintf(logfile, "# Perplexity Results #\n");
fprintf(logfile, "######################\n");
fprintf(logfile, "\n");
dump_vector_float_yaml(logfile, "logits", results.logits);
fprintf(logfile, "ppl_value: %f\n", results.ppl_value);
dump_vector_float_yaml(logfile, "probs", results.probs);
llama_dump_timing_info_yaml(logfile, ctx);
fclose(logfile);
}
static std::vector<float> softmax(const std::vector<float>& logits) {
std::vector<float> probs(logits.size());
float max_logit = logits[0];
for (float v : logits) {
max_logit = std::max(max_logit, v);
}
double sum_exp = 0.0;
for (size_t i = 0; i < logits.size(); i++) {
// Subtract the maximum logit value from the current logit value for numerical stability
const float logit = logits[i] - max_logit;
const float exp_logit = expf(logit);
sum_exp += exp_logit;
probs[i] = exp_logit;
}
for (size_t i = 0; i < probs.size(); i++) {
probs[i] /= sum_exp;
}
return probs;
}
static results_log_softmax log_softmax(int n_vocab, const float * logits, int tok) {
float max_logit = logits[0];
for (int i = 1; i < n_vocab; ++i) {
max_logit = std::max(max_logit, logits[i]);
}
double sum_exp = 0.0;
for (int i = 0; i < n_vocab; ++i) {
sum_exp += expf(logits[i] - max_logit);
}
return {logits[tok] - max_logit - log(sum_exp), logits[tok], expf(logits[tok] - max_logit) / (float) sum_exp};
}
static inline int nearest_int(float fval) {
//assert(fval <= 4194303.f);
float val = fval + 12582912.f;
int i; memcpy(&i, &val, sizeof(int));
return (i & 0x007fffff) - 0x00400000;
}
static double log_softmax(int n_vocab, const float * logits, uint16_t * log_prob, int tok) {
float max_logit = logits[0];
float min_logit = logits[0];
for (int i = 1; i < n_vocab; ++i) {
max_logit = std::max(max_logit, logits[i]);
min_logit = std::min(min_logit, logits[i]);
}
min_logit = std::max(min_logit, max_logit - 16);
double sum_exp = 0.0;
for (int i = 0; i < n_vocab; ++i) {
sum_exp += expf(logits[i] - max_logit);
}
const float log_sum_exp = log(sum_exp);
const float min_log_prob = min_logit - max_logit - log_sum_exp;
const float scale = (max_logit - min_logit)/65535.f;
float * d = (float *)log_prob;
d[0] = scale;
d[1] = min_log_prob;
log_prob += 4;
if (scale) {
const float inv_scale = 1/scale;
for (int i = 0; i < n_vocab; ++i) {
log_prob[i] = logits[i] > min_logit ? nearest_int(inv_scale*(logits[i] - min_logit)) : 0;
}
} else {
std::memset(log_prob, 0, n_vocab*sizeof(uint16_t));
}
return max_logit + log_sum_exp - logits[tok];
}
static void process_logits(
int n_vocab, const float * logits, const int * tokens, int n_token, std::vector<std::thread> & workers,
double & nll, double & nll2, float * logit_history, float * prob_history
) {
std::mutex mutex;
int counter = 0;
auto compute = [&mutex, &counter, &nll, &nll2, logit_history, prob_history, n_vocab, logits, tokens, n_token] () {
double local_nll = 0;
double local_nll2 = 0;
while (true) {
std::unique_lock<std::mutex> lock(mutex);
int i = counter++;
if (i >= n_token) {
nll += local_nll; nll2 += local_nll2;
break;
}
lock.unlock();
const results_log_softmax results = log_softmax(n_vocab, logits + i*n_vocab, tokens[i+1]);
const double v = -results.log_softmax;
local_nll += v;
local_nll2 += v*v;
logit_history[i] = results.logit;
prob_history[i] = results.prob;
}
};
for (auto & w : workers) {
w = std::thread(compute);
}
compute();
for (auto & w : workers) {
w.join();
}
}
static void process_logits(std::ostream& out, int n_vocab, const float * logits, const int * tokens, int n_token,
std::vector<std::thread> & workers, std::vector<uint16_t> & log_probs, double & nll, double & nll2) {
std::mutex mutex;
const int nv = 2*((n_vocab + 1)/2) + 4;
int counter = 0;
auto compute = [&mutex, &counter, &log_probs, &nll, &nll2, n_vocab, logits, tokens, n_token, nv] () {
double local_nll = 0;
double local_nll2 = 0;
while (true) {
std::unique_lock<std::mutex> lock(mutex);
int i = counter++;
if (i >= n_token) {
nll += local_nll; nll2 += local_nll2;
break;
}
lock.unlock();
const double v = log_softmax(n_vocab, logits + i*n_vocab, log_probs.data() + i*nv, tokens[i+1]);
local_nll += v;
local_nll2 += v*v;
}
};
for (auto & w : workers) {
w = std::thread(compute);
}
compute();
for (auto & w : workers) {
w.join();
}
out.write((const char *)log_probs.data(), n_token*nv*sizeof(uint16_t));
}
struct kl_divergence_result {
double sum_nll = 0;
double sum_nll2 = 0;
double sum_kld = 0;
double sum_kld2 = 0;
double sum_nll_diff = 0;
double sum_nll_diff2 = 0;
size_t n_same_top = 0;
size_t count = 0;
};
static double log_softmax(int n_vocab, const float * logits, const uint16_t * base_log_prob, int tok, kl_divergence_result & kld) {
float max_logit = logits[0];
int imax = 0;
for (int i = 1; i < n_vocab; ++i) {
if (logits[i] > max_logit) {
max_logit = logits[i];
imax = i;
}
}
double sum_exp = 0.0;
for (int i = 0; i < n_vocab; ++i) {
sum_exp += expf(logits[i] - max_logit);
}
const float log_sum_exp = log(sum_exp);
const float * d = (const float *)base_log_prob;
const float scale = d[0];
const float min_log_prob = d[1];
base_log_prob += 4;
float nll = max_logit + log_sum_exp - logits[tok];
kld.sum_nll += nll;
kld.sum_nll2 += nll*nll;
nll += (scale*base_log_prob[tok] + min_log_prob);
kld.sum_nll_diff += nll;
kld.sum_nll_diff2 += nll*nll;
max_logit += log_sum_exp;
double sum = 0;
int imax_base = -1;
float p_log_base_max = 0;
for (int i = 0; i < n_vocab; ++i) {
const float p_log_base = scale*base_log_prob[i] + min_log_prob;
if (i == 0 || p_log_base > p_log_base_max) {
p_log_base_max = p_log_base;
imax_base = i;
}
if (p_log_base > -16.f) {
const float p_base = expf(p_log_base);
sum += p_base * (p_log_base - logits[i] + max_logit);
}
}
kld.sum_kld += sum;
kld.sum_kld2 += sum*sum;
++kld.count;
if (imax == imax_base) ++kld.n_same_top;
return sum;
}
static void process_logits(int n_vocab, const float * logits, const int * tokens, int n_token,
std::vector<std::thread> & workers, const std::vector<uint16_t> & base_log_probs, kl_divergence_result & kld,
float * kld_values) {
std::mutex mutex;
const int nv = 2*((n_vocab + 1)/2) + 4;
int counter = 0;
auto compute = [&mutex, &counter, &base_log_probs, &kld, n_vocab, logits, tokens, n_token, nv, kld_values] () {
kl_divergence_result local_kld;
while (true) {
std::unique_lock<std::mutex> lock(mutex);
int i = counter++;
if (i >= n_token) {
kld.sum_nll += local_kld.sum_nll;
kld.sum_nll2 += local_kld.sum_nll2;
kld.sum_kld += local_kld.sum_kld;
kld.sum_kld2 += local_kld.sum_kld2;
kld.sum_nll_diff += local_kld.sum_nll_diff;
kld.sum_nll_diff2 += local_kld.sum_nll_diff2;
kld.n_same_top += local_kld.n_same_top;
kld.count += local_kld.count;
break;
}
lock.unlock();
double v = log_softmax(n_vocab, logits + i*n_vocab, base_log_probs.data() + i*nv, tokens[i+1], local_kld);
kld_values[i] = (float)v;
}
};
for (auto & w : workers) {
w = std::thread(compute);
}
compute();
for (auto & w : workers) {
w.join();
}
}
static results_perplexity perplexity_v2(llama_context * ctx, const gpt_params & params) {
// Download: https://huggingface.co/datasets/ggml-org/ci/resolve/main/wikitext-2-raw-v1.zip
// Run `./perplexity -m models/7B/ggml-model-q4_0.bin -f wiki.test.raw`
// Output: `perplexity: 13.5106 [114/114]`
// BOS tokens will be added for each chunk before eval
const bool add_bos = llama_should_add_bos_token(llama_get_model(ctx));
fprintf(stderr, "%s: tokenizing the input ..\n", __func__);
std::vector<llama_token> tokens = ::llama_tokenize(ctx, params.prompt, add_bos);
const int n_ctx = llama_n_ctx(ctx);
if (int(tokens.size()) < 2*n_ctx) {
fprintf(stderr, "%s: you need at least %d tokens to evaluate perplexity with a context of %d\n",__func__,2*n_ctx,
n_ctx);
fprintf(stderr, "%s: the data file you provided tokenizes to only %zu tokens\n",__func__,tokens.size());
return {std::move(tokens), 0., {}, {}};
}
std::vector<float> logit_history;
std::vector<float> prob_history;
logit_history.resize(tokens.size());
prob_history.resize(tokens.size());
if (params.ppl_stride <= 0) {
fprintf(stderr, "%s: stride is %d but must be greater than zero!\n",__func__,params.ppl_stride);
return {tokens, -1, logit_history, prob_history};
}
const int calc_chunk = n_ctx;
fprintf(stderr, "%s: have %zu tokens. Calculation chunk = %d\n", __func__, tokens.size(), calc_chunk);
if (int(tokens.size()) <= calc_chunk) {
fprintf(stderr, "%s: there are only %zu tokens, this is not enough for a context size of %d and stride %d\n",__func__,
tokens.size(), n_ctx, params.ppl_stride);
return {tokens, -1, logit_history, prob_history};
}
const int n_chunk_max = (tokens.size() - calc_chunk + params.ppl_stride - 1) / params.ppl_stride;
const int n_chunk = params.n_chunks < 0 ? n_chunk_max : std::min(params.n_chunks, n_chunk_max);
const int n_vocab = llama_n_vocab(llama_get_model(ctx));
const int n_batch = params.n_batch;
int count = 0;
double nll = 0.0;
fprintf(stderr, "%s: calculating perplexity over %d chunks, batch_size=%d\n", __func__, n_chunk, n_batch);
for (int i = 0; i < n_chunk; ++i) {
const int start = i * params.ppl_stride;
const int end = start + calc_chunk;
const int num_batches = (calc_chunk + n_batch - 1) / n_batch;
//fprintf(stderr, "%s: evaluating %d...%d using %d batches\n", __func__, start, end, num_batches);
std::vector<float> logits;
const auto t_start = std::chrono::high_resolution_clock::now();
// clear the KV cache
llama_kv_cache_clear(ctx);
for (int j = 0; j < num_batches; ++j) {
const int batch_start = start + j * n_batch;
const int batch_size = std::min(end - batch_start, n_batch);
//fprintf(stderr, " Batch %d: starts at %d, size is %d, n_past is %d\n",j,batch_start,batch_size,j * n_batch);
if (llama_decode(ctx, llama_batch_get_one(tokens.data() + batch_start, batch_size, j * n_batch, 0))) {
//fprintf(stderr, "%s : failed to eval\n", __func__);
return {tokens, -1, logit_history, prob_history};
}
// save original token and restore it after eval
const auto token_org = tokens[batch_start];
// add BOS token for the first batch of each chunk
if (add_bos && j == 0) {
tokens[batch_start] = llama_token_bos(llama_get_model(ctx));
}
const auto batch_logits = llama_get_logits(ctx);
logits.insert(logits.end(), batch_logits, batch_logits + batch_size * n_vocab);
if (j == 0) {
tokens[batch_start] = token_org;
}
}
const auto t_end = std::chrono::high_resolution_clock::now();
if (i == 0) {
const float t_total = std::chrono::duration<float>(t_end - t_start).count();
fprintf(stderr, "%s: %.2f seconds per pass - ETA ", __func__, t_total);
int total_seconds = (int)(t_total * n_chunk);
if (total_seconds >= 60*60) {
fprintf(stderr, "%d hours ", total_seconds / (60*60));
total_seconds = total_seconds % (60*60);
}
fprintf(stderr, "%.2f minutes\n", total_seconds / 60.0);
}
//fprintf(stderr, "%s: using tokens %d...%d\n",__func__,params.n_ctx - params.ppl_stride + start, params.n_ctx + start);
for (int j = n_ctx - params.ppl_stride - 1; j < n_ctx - 1; ++j) {
// Calculate probability of next token, given the previous ones.
const std::vector<float> tok_logits(
logits.begin() + (j + 0) * n_vocab,
logits.begin() + (j + 1) * n_vocab);
const float prob = softmax(tok_logits)[tokens[start + j + 1]];
logit_history[start + j + 1] = tok_logits[tokens[start + j + 1]];
prob_history[start + j + 1] = prob;
nll += -std::log(prob);
++count;
}
// perplexity is e^(average negative log-likelihood)
if (params.ppl_output_type == 0) {
printf("[%d]%.4lf,", i + 1, std::exp(nll / count));
} else {
printf("%8d %.4lf\n", i*params.ppl_stride, std::exp(nll / count));
}
fflush(stdout);
}
printf("\n");
return {tokens, std::exp(nll / count), logit_history, prob_history};
}
static results_perplexity perplexity(llama_context * ctx, const gpt_params & params) {
if (params.ppl_stride > 0) {
return perplexity_v2(ctx, params);
}
// Download: https://huggingface.co/datasets/ggml-org/ci/resolve/main/wikitext-2-raw-v1.zip
// Run `./perplexity -m models/7B/ggml-model-q4_0.bin -f wiki.test.raw`
// Output: `perplexity: 13.5106 [114/114]`
// BOS tokens will be added for each chunk before eval
const bool add_bos = llama_should_add_bos_token(llama_get_model(ctx));
const int n_ctx = llama_n_ctx(ctx);
std::ofstream logits_stream;
if (!params.logits_file.empty()) {
logits_stream.open(params.logits_file.c_str(), std::ios::binary);
if (!logits_stream.is_open()) {
fprintf(stderr, "%s: failed to open %s for writing\n", __func__, params.logits_file.c_str());
return {};
}
fprintf(stderr, "%s: saving all logits to %s\n", __func__, params.logits_file.c_str());
logits_stream.write("_logits_", 8);
logits_stream.write(reinterpret_cast<const char *>(&n_ctx), sizeof(n_ctx));
}
auto tim1 = std::chrono::high_resolution_clock::now();
fprintf(stderr, "%s: tokenizing the input ..\n", __func__);
std::vector<llama_token> tokens = ::llama_tokenize(ctx, params.prompt, add_bos);
auto tim2 = std::chrono::high_resolution_clock::now();
fprintf(stderr, "%s: tokenization took %g ms\n",__func__,1e-3*std::chrono::duration_cast<std::chrono::microseconds>(tim2-tim1).count());
if (int(tokens.size()) < 2*n_ctx) {
fprintf(stderr, "%s: you need at least %d tokens to evaluate perplexity with a context of %d\n",__func__,2*n_ctx,
n_ctx);
fprintf(stderr, "%s: the data file you provided tokenizes to only %zu tokens\n",__func__,tokens.size());
return {std::move(tokens), 0., {}, {}};
}
std::vector<float> logit_history;
logit_history.resize(tokens.size());
std::vector<float> prob_history;
prob_history.resize(tokens.size());
const int n_chunk_max = tokens.size() / n_ctx;
const int n_chunk = params.n_chunks < 0 ? n_chunk_max : std::min(params.n_chunks, n_chunk_max);
const int n_vocab = llama_n_vocab(llama_get_model(ctx));
const int n_batch = params.n_batch;
int count = 0;
double nll = 0.0;
double nll2 = 0.0;
const int num_batches = (n_ctx + n_batch - 1) / n_batch;
std::vector<float> logits;
if (num_batches > 1) {
logits.reserve((size_t)n_ctx * n_vocab);
}
fprintf(stderr, "%s: calculating perplexity over %d chunks, batch_size=%d\n", __func__, n_chunk, n_batch);
std::vector<std::thread> workers(std::thread::hardware_concurrency() - 1);
std::vector<uint16_t> log_probs;
if (!params.logits_file.empty()) {
logits_stream.write((const char *)&n_vocab, sizeof(n_vocab));
logits_stream.write((const char *)&n_chunk, sizeof(n_chunk));
logits_stream.write((const char *)tokens.data(), n_chunk*n_ctx*sizeof(tokens[0]));
const int nv = 2*((n_vocab + 1)/2) + 4;
log_probs.resize(n_ctx * nv);
}
for (int i = 0; i < n_chunk; ++i) {
const int start = i * n_ctx;
const int end = start + n_ctx;
const auto t_start = std::chrono::high_resolution_clock::now();
// clear the KV cache
llama_kv_cache_clear(ctx);
for (int j = 0; j < num_batches; ++j) {
const int batch_start = start + j * n_batch;
const int batch_size = std::min(end - batch_start, n_batch);
// save original token and restore it after eval
const auto token_org = tokens[batch_start];
// add BOS token for the first batch of each chunk
if (add_bos && j == 0) {
tokens[batch_start] = llama_token_bos(llama_get_model(ctx));
}
if (llama_decode(ctx, llama_batch_get_one(tokens.data() + batch_start, batch_size, j * n_batch, 0))) {
fprintf(stderr, "%s : failed to eval\n", __func__);
return {tokens, -1, logit_history, prob_history};
}
// restore the original token in case it was set to BOS
tokens[batch_start] = token_org;
if (num_batches > 1) {
const auto * batch_logits = llama_get_logits(ctx);
logits.insert(logits.end(), batch_logits, batch_logits + batch_size * n_vocab);
}
}
const auto t_end = std::chrono::high_resolution_clock::now();
if (i == 0) {
const float t_total = std::chrono::duration<float>(t_end - t_start).count();
fprintf(stderr, "%s: %.2f seconds per pass - ETA ", __func__, t_total);
int total_seconds = (int)(t_total * n_chunk);
if (total_seconds >= 60*60) {
fprintf(stderr, "%d hours ", total_seconds / (60*60));
total_seconds = total_seconds % (60*60);
}
fprintf(stderr, "%.2f minutes\n", total_seconds / 60.0);
}
// We get the logits for all the tokens in the context window (params.n_ctx)
// from llama_eval above. Now, based on https://huggingface.co/docs/transformers/perplexity,
// calculate the perplexity over the last half of the window (so the model always has
// some context to predict the token).
//
// We rely on the fact that attention in the forward pass only looks at previous
// tokens here, so the logits returned for each token are an accurate representation
// of what the model would have predicted at that point.
//
// Example, we have a context window of 512, we will compute perplexity for each of the
// last 256 tokens. Then, we split the input up into context window size chunks to
// process the entire prompt.
const int first = n_ctx/2;
const float * all_logits = num_batches > 1 ? logits.data() : llama_get_logits(ctx);
if (!params.logits_file.empty()) {
process_logits(logits_stream, n_vocab, all_logits + first*n_vocab, tokens.data() + start + first, n_ctx - 1 - first,
workers, log_probs, nll, nll2);
} else {
process_logits(n_vocab, all_logits + first*n_vocab, tokens.data() + start + first, n_ctx - 1 - first,
workers, nll, nll2, logit_history.data() + start + first, prob_history.data() + start + first);
}
count += n_ctx - first - 1;
// perplexity is e^(average negative log-likelihood)
if (params.ppl_output_type == 0) {
printf("[%d]%.4lf,", i + 1, std::exp(nll / count));
} else {
double av = nll/count;
double av2 = nll2/count - av*av;
if (av2 > 0) av2 = sqrt(av2/(count-1));
printf("%8d %.4lf %4lf %4lf\n", i*n_ctx, std::exp(nll / count), av, av2);
}
fflush(stdout);
logits.clear();
}
printf("\n");
nll2 /= count;
nll /= count;
const double ppl = exp(nll);
nll2 -= nll * nll;
if (nll2 > 0) {
nll2 = sqrt(nll2/(count-1));
printf("Final estimate: PPL = %.4lf +/- %.5lf\n", ppl, nll2*ppl);
} else {
printf("Unexpected negative standard deviation of log(prob)\n");
}
return {tokens, ppl, logit_history, prob_history};
}
static bool decode_helper(llama_context * ctx, llama_batch & batch, std::vector<float> & batch_logits, int32_t n_batch, int32_t n_vocab) {
for (int32_t i = 0; i < (int32_t) batch.n_tokens; i += n_batch) {
const int32_t n_tokens = std::min(n_batch, (int32_t) (batch.n_tokens - i));
llama_batch batch_view = {
n_tokens,
batch.token + i,
nullptr,
batch.pos + i,
batch.n_seq_id + i,
batch.seq_id + i,
batch.logits + i,
0, 0, 0, // unused
};
const int ret = llama_decode(ctx, batch_view);
if (ret != 0) {
LOG_TEE("failed to decode the batch, n_batch = %d, ret = %d\n", n_batch, ret);
return false;
}
memcpy(batch_logits.data() + i*n_vocab, llama_get_logits(ctx), n_tokens*n_vocab*sizeof(float));
}
return true;
}
#define K_TOKEN_CHUNK 4
static void compute_logprobs(const float * batch_logits, int n_vocab, std::vector<std::thread>& workers,
const std::vector<std::pair<size_t, llama_token>>& eval_pairs, std::vector<float>& eval_results) {
if (eval_results.size() != eval_pairs.size()) {
eval_results.resize(eval_pairs.size());
}
if (eval_pairs.empty()) return;
size_t max_threads = std::min((eval_pairs.size() + K_TOKEN_CHUNK - 1)/K_TOKEN_CHUNK, workers.size());
std::atomic<int> counter(0);
auto compute = [&counter, &eval_pairs, &eval_results, batch_logits, n_vocab] () {
float local_logprobs[K_TOKEN_CHUNK];
while (true) {
size_t first = counter.fetch_add(K_TOKEN_CHUNK, std::memory_order_relaxed);
if (first >= eval_results.size()) break;
size_t last = std::min(first + K_TOKEN_CHUNK, eval_results.size());
for (size_t i = first; i < last; ++i) {
auto logits = batch_logits + eval_pairs[i].first * n_vocab;
float max_logit = logits[0];
for (int j = 1; j < n_vocab; ++j) {
max_logit = std::max(max_logit, logits[j]);
}
float sum_p = 0.f;
for (int j = 0; j < n_vocab; ++j) {
sum_p += expf(logits[j] - max_logit);
}
local_logprobs[i - first] = logits[eval_pairs[i].second] - max_logit - std::log(sum_p);
}
std::memcpy(eval_results.data() + first, local_logprobs, (last - first)*sizeof(float));
}
};
for (size_t it = 0; it < max_threads; ++it) {
workers[it] = std::thread(compute);
}
for (size_t it = 0; it < max_threads; ++it) {
workers[it].join();
}
}
static void hellaswag_score(llama_context * ctx, const gpt_params & params) {
// Calculates hellaswag score (acc_norm) from prompt
//
// Data extracted from the HellaSwag validation dataset (MIT license) https://github.com/rowanz/hellaswag/blob/master/data/hellaswag_val.jsonl
// All used data fields are preprocessed as in https://github.com/EleutherAI/lm-evaluation-harness/blob/df3da98c5405deafd519c2ddca52bb7c3fe36bef/lm_eval/tasks/hellaswag.py#L62-L68
//
// All 10042 tasks should be extracted to keep the results standardized like other implementations.
//
// Datafile layout:
// ['??'] denotes json fields
// 6 lines per task:
// ['activity_label'] + ": " +['ctx'] - The first part of the query, the context
// ['label'] - The index the best common sense ending aka gold ending
// ['endings'][0] - Endings added to the first part of the query
// ['endings'][1]
// ['endings'][2]
// ['endings'][3]
std::vector<std::string> prompt_lines;
std::istringstream strstream(params.prompt);
std::string line;
while (std::getline(strstream,line,'\n')) {
prompt_lines.push_back(line);
}
if (prompt_lines.size() % 6 != 0) {
fprintf(stderr, "%s : number of lines in prompt not a multiple of 6.\n", __func__);
return;
}
size_t hs_task_count = prompt_lines.size()/6;
fprintf(stderr, "%s : loaded %zu tasks from prompt.\n", __func__, hs_task_count);
const bool is_spm = llama_vocab_type(llama_get_model(ctx)) == LLAMA_VOCAB_TYPE_SPM;
fprintf(stderr, "================================= is_spm = %d\n", is_spm);
// This is needed as usual for LLaMA models
const bool add_bos = llama_should_add_bos_token(llama_get_model(ctx));
// The tasks should be randomized so the score stabilizes quickly.
bool randomize_tasks = true;
// Number of tasks to use when computing the score
if (params.hellaswag_tasks < hs_task_count) {
hs_task_count = params.hellaswag_tasks;
}
// The random seed should not impact the final result if the computation is done over enough tasks, so kept hardcoded for now
std::mt19937 rng(1);
// Dataholder for hellaswag tasks
struct hs_data_t {
std::string context;
size_t gold_ending_idx;
std::string ending[4];
size_t ending_logprob_count[4];
double ending_logprob[4];
size_t i_batch; // starting index in the llama_batch
size_t common_prefix; // max number of initial tokens that are the same in all sentences
size_t required_tokens; // needed number of tokens to evaluate all 4 endings
std::vector<llama_token> seq_tokens[4];
};
fprintf(stderr, "%s : selecting %zu %s tasks.\n", __func__, hs_task_count, (randomize_tasks?"randomized":"the first") );
// Select and read data from prompt lines
std::vector<hs_data_t> hs_data(hs_task_count);
for (size_t i = 0; i < hs_task_count; i++) {
size_t idx = i;
auto & hs_cur = hs_data[i];
// Select a random example of those left in the prompt
if (randomize_tasks) {
std::uniform_int_distribution<size_t> dist(0, prompt_lines.size()/6-1 ) ;
idx = dist(rng);
}
hs_cur.context = prompt_lines[idx*6];
hs_cur.gold_ending_idx = std::stoi( prompt_lines[idx*6+1] );
for (size_t j = 0; j < 4; j++) {
hs_cur.ending[j] = prompt_lines[idx*6+2+j];
hs_cur.seq_tokens[j] = ::llama_tokenize(ctx, hs_cur.context + " " + hs_cur.ending[j], add_bos);
}
// determine the common prefix of the endings
hs_cur.common_prefix = 0;
for (size_t k = 0; k < hs_cur.seq_tokens[0].size(); k++) {
if (hs_cur.seq_tokens[0][k] != hs_cur.seq_tokens[1][k] ||
hs_cur.seq_tokens[0][k] != hs_cur.seq_tokens[2][k] ||
hs_cur.seq_tokens[0][k] != hs_cur.seq_tokens[3][k]) {
break;
}
hs_cur.common_prefix++;
}
hs_cur.required_tokens = hs_cur.common_prefix +
hs_cur.seq_tokens[0].size() - hs_cur.common_prefix +
hs_cur.seq_tokens[1].size() - hs_cur.common_prefix +
hs_cur.seq_tokens[2].size() - hs_cur.common_prefix +
hs_cur.seq_tokens[3].size() - hs_cur.common_prefix;
//GGML_ASSERT(hs_cur.common_prefix >= ::llama_tokenize(ctx, hs_cur.context, add_bos).size());
// Delete the selected random example from the prompt
if (randomize_tasks) {
prompt_lines.erase( std::next(prompt_lines.begin(),idx*6) , std::next(prompt_lines.begin(),idx*6+6) );
}
}
fprintf(stderr, "%s : calculating hellaswag score over selected tasks.\n", __func__);
printf("\ntask\tacc_norm\n");
double acc = 0.0f;
const int n_vocab = llama_n_vocab(llama_get_model(ctx));
const int n_ctx = llama_n_ctx(ctx);
const int n_batch = params.n_batch;
const int max_tasks_per_batch = 32;
const int max_seq = 4*max_tasks_per_batch;
llama_batch batch = llama_batch_init(n_ctx, 0, max_seq);
std::vector<float> tok_logits(n_vocab);
std::vector<float> batch_logits(n_vocab*n_ctx);
std::vector<std::pair<size_t, llama_token>> eval_pairs;
std::vector<float> eval_results;
std::vector<std::thread> workers(std::thread::hardware_concurrency());
for (size_t i0 = 0; i0 < hs_task_count; i0++) {
int n_cur = 0;
size_t i1 = i0;
size_t i_batch = 0; // this tells us where in `llama_batch` we are currently
llama_batch_clear(batch);
// batch as much tasks as possible into the available context
// each task has 4 unique seuqnce ids - one for each ending
// the common prefix is shared among the 4 sequences to save tokens
// we extract logits only from the last common token and from all ending tokens of each sequence
while (n_cur + (int) hs_data[i1].required_tokens <= n_ctx) {
auto & hs_cur = hs_data[i1];
const int s0 = 4*(i1 - i0);
if (s0 + 4 > max_seq) {
break;
}
for (size_t i = 0; i < hs_cur.common_prefix; ++i) {
llama_batch_add(batch, hs_cur.seq_tokens[0][i], i, { s0 + 0, s0 + 1, s0 + 2, s0 + 3}, false);
}
batch.logits[batch.n_tokens - 1] = true; // we need logits for the last token of the common prefix
for (int s = 0; s < 4; ++s) {
for (size_t i = hs_cur.common_prefix; i < hs_cur.seq_tokens[s].size(); ++i) {
llama_batch_add(batch, hs_cur.seq_tokens[s][i], i, { s0 + s }, true);
}
}
hs_cur.i_batch = i_batch;
i_batch += hs_cur.required_tokens;
n_cur += hs_data[i1].required_tokens;
if (++i1 == hs_task_count) {
break;
}
}
if (i0 == i1) {
fprintf(stderr, "%s : task %zu does not fit in the context window\n", __func__, i0);
return;
}
llama_kv_cache_clear(ctx);
// decode all tasks [i0, i1)
if (!decode_helper(ctx, batch, batch_logits, n_batch, n_vocab)) {
fprintf(stderr, "%s: llama_decode() failed\n", __func__);
return;
}
// Compute log-probs in parallel
// First we collect all tasks
eval_pairs.clear();
for (size_t i = i0; i < i1; ++i) {
auto & hs_cur = hs_data[i];
size_t li = hs_cur.common_prefix;
for (int s = 0; s < 4; ++s) {
for (size_t j = hs_cur.common_prefix; j < hs_cur.seq_tokens[s].size() - 1; j++) {
eval_pairs.emplace_back(hs_cur.i_batch + li++, hs_cur.seq_tokens[s][j + 1]);
}
++li;
}
}
// Then we do the actual calculation
compute_logprobs(batch_logits.data(), n_vocab, workers, eval_pairs, eval_results);
size_t ir = 0;
// compute the logprobs for each ending of the decoded tasks
for (size_t i = i0; i < i1; ++i) {
auto & hs_cur = hs_data[i];
std::memcpy(tok_logits.data(), batch_logits.data() + n_vocab*(hs_cur.i_batch + hs_cur.common_prefix - 1), n_vocab*sizeof(float));
const auto first_probs = softmax(tok_logits);
for (int s = 0; s < 4; ++s) {
hs_cur.ending_logprob_count[s] = 1;
hs_cur.ending_logprob[s] = std::log(first_probs[hs_cur.seq_tokens[s][hs_cur.common_prefix]]);
for (size_t j = hs_cur.common_prefix; j < hs_cur.seq_tokens[s].size() - 1; j++) {
hs_cur.ending_logprob[s] += eval_results[ir++];
hs_cur.ending_logprob_count[s]++;
}
hs_cur.ending_logprob[s] /= hs_cur.ending_logprob_count[s];
}
// Find the ending with maximum logprob
size_t ending_logprob_max_idx = 0;
double ending_logprob_max_val = hs_cur.ending_logprob[0];
for (size_t s = 1; s < 4; s++) {
if (hs_cur.ending_logprob[s] > ending_logprob_max_val) {
ending_logprob_max_idx = s;
ending_logprob_max_val = hs_cur.ending_logprob[s];
}
}
//printf("max logprob ending idx %lu, gold ending idx %lu\n", ending_logprob_max_idx, hs_cur.gold_ending_idx);
// If the gold ending got the maximum logprobe add one accuracy point
if (ending_logprob_max_idx == hs_cur.gold_ending_idx) {
acc += 1.0;
}
// Print the accumulated accuracy mean x 100
printf("%zu\t%.8lf\n", i + 1, acc/double(i + 1)*100.0);
fflush(stdout);
}
i0 = i1 - 1;
}
llama_batch_free(batch);
printf("\n");
}
struct winogrande_entry {
std::string first;
std::string second;
std::array<std::string, 2> choices;
int answer;
size_t i_batch;
size_t common_prefix;
size_t required_tokens;
size_t n_base1; // number of tokens for context + choice 1
size_t n_base2; // number of tokens for context + choice 2
std::vector<llama_token> seq_tokens[2];
};
static std::vector<winogrande_entry> load_winogrande_from_csv(const std::string& prompt) {
std::vector<winogrande_entry> result;
std::istringstream in(prompt);
std::string line;
std::array<int, 4> comma_pos;
while (true) {
std::getline(in, line);
if (in.fail() || in.eof()) break;
int ipos = 0;
bool quote_open = false;
for (int i = 0; i < int(line.size()); ++i) {
if (!quote_open) {
if (line[i] == ',') {
comma_pos[ipos++] = i;
if (ipos == 4) break;
}
else if (line[i] == '"') {
quote_open = true;
}
}
else {
if (line[i] == '"') {
quote_open = false;
}
}
}
if (ipos != 4) {
printf("%s: failed to find comma separators in <%s>\n", __func__, line.c_str());
continue;
}
auto sentence = line[comma_pos[0]+1] == '"' ? line.substr(comma_pos[0]+2, comma_pos[1] - comma_pos[0] - 3)
: line.substr(comma_pos[0]+1, comma_pos[1] - comma_pos[0] - 1);
auto choice1 = line.substr(comma_pos[1]+1, comma_pos[2] - comma_pos[1] - 1);
auto choice2 = line.substr(comma_pos[2]+1, comma_pos[3] - comma_pos[2] - 1);
auto answer = line.substr(comma_pos[3]+1, line.size() - comma_pos[3] - 1);
auto index = line.substr(0, comma_pos[0]);
int where = 0;
for ( ; where < int(sentence.size()); ++where) {
if (sentence[where] == '_') break;
}
if (where == int(sentence.size())) {
printf("%s: no _ in <%s>\n", __func__, sentence.c_str());
continue;
}
std::istringstream stream(answer.c_str());
int i_answer; stream >> i_answer;
if (stream.fail() || i_answer < 1 || i_answer > 2) {
printf("%s: failed to parse answer <%s>\n", __func__, answer.c_str());
continue;
}
result.emplace_back();
auto& wg = result.back();
wg.first = sentence.substr(0, where);
wg.second = sentence.substr(where + 1, sentence.size() - where - 1);
wg.choices[0] = std::move(choice1);
wg.choices[1] = std::move(choice2);
wg.answer = i_answer;
}
return result;
}
/*
* Evaluates the Winogrande score.
* Uses a CSV containing task index, dentence, choice 1, choice 2, answer (1 or 2)
* You can get one such dataset from e.g. https://huggingface.co/datasets/ikawrakow/winogrande-eval-for-llama.cpp
* As an example, the 1st row in the above dataset is
*
* 0,Sarah was a much better surgeon than Maria so _ always got the easier cases.,Sarah,Maria,2
*
*/
static void winogrande_score(llama_context * ctx, const gpt_params & params) {
constexpr int k_min_trailing_ctx = 3;
auto data = load_winogrande_from_csv(params.prompt);
if (data.empty()) {
fprintf(stderr, "%s: no tasks\n", __func__);
return;
}
fprintf(stderr, "%s : loaded %zu tasks from prompt.\n", __func__, data.size());
if (params.winogrande_tasks > 0 && params.winogrande_tasks < data.size()) {
fprintf(stderr, "%s : selecting %zu random tasks\n", __func__, params.winogrande_tasks);
std::mt19937 rng(1);
std::vector<int> aux(data.size());
for (int i = 0; i < int(data.size()); ++i) {
aux[i] = i;
}
float scale = 1/(1.f + (float)rng.max());
std::vector<winogrande_entry> selected;
selected.resize(params.winogrande_tasks);
for (int i = 0; i < int(params.winogrande_tasks); ++i) {
int j = int(scale*rng()*aux.size());
selected[i] = std::move(data[aux[j]]);
aux[j] = aux.back();
aux.pop_back();
}
data = std::move(selected);
}
fprintf(stderr, "%s : tokenizing selected tasks\n", __func__);
// This is needed as usual for LLaMA models
const bool add_bos = llama_should_add_bos_token(llama_get_model(ctx));
for (auto & task : data) {
task.seq_tokens[0] = ::llama_tokenize(ctx, task.first + task.choices[0] + task.second, add_bos);
task.seq_tokens[1] = ::llama_tokenize(ctx, task.first + task.choices[1] + task.second, add_bos);
task.common_prefix = 0;
for (size_t k = 0; k < task.seq_tokens[0].size(); k++) {
if (task.seq_tokens[0][k] != task.seq_tokens[1][k]) {
break;
}
task.common_prefix++;
}
task.required_tokens = task.common_prefix +
task.seq_tokens[0].size() - task.common_prefix +
task.seq_tokens[1].size() - task.common_prefix;
task.n_base1 = ::llama_tokenize(ctx, task.first + task.choices[0], add_bos).size();
task.n_base2 = ::llama_tokenize(ctx, task.first + task.choices[1], add_bos).size();
}
fprintf(stderr, "%s : calculating winogrande score over selected tasks.\n", __func__);
const int n_vocab = llama_n_vocab(llama_get_model(ctx));
const int n_ctx = llama_n_ctx(ctx);
const int n_batch = params.n_batch;
const int max_tasks_per_batch = 128;
const int max_seq = 2*max_tasks_per_batch;
llama_batch batch = llama_batch_init(n_ctx, 0, max_seq);
std::vector<float> tok_logits(n_vocab);
std::vector<float> batch_logits(n_vocab*n_ctx);
std::vector<std::pair<size_t, llama_token>> eval_pairs;
std::vector<float> eval_results;
std::vector<std::thread> workers(std::thread::hardware_concurrency());
int n_correct = 0;
int n_done = 0;
for (size_t i0 = 0; i0 < data.size(); i0++) {
int n_cur = 0;
size_t i1 = i0;
size_t i_batch = 0;
llama_batch_clear(batch);
while (n_cur + (int) data[i1].required_tokens <= n_ctx) {
const int s0 = 2*(i1 - i0);
if (s0 + 2 > max_seq) {
break;
}
for (size_t i = 0; i < data[i1].common_prefix; ++i) {
llama_batch_add(batch, data[i1].seq_tokens[0][i], i, { s0 + 0, s0 + 1}, false);
}
batch.logits[batch.n_tokens - 1] = true;
for (int s = 0; s < 2; ++s) {
for (size_t i = data[i1].common_prefix; i < data[i1].seq_tokens[s].size(); ++i) {
llama_batch_add(batch, data[i1].seq_tokens[s][i], i, { s0 + s }, true);
}
}
data[i1].i_batch = i_batch;
i_batch += data[i1].required_tokens;
n_cur += data[i1].required_tokens;
if (++i1 == data.size()) {
break;
}
}
if (i0 == i1) {
fprintf(stderr, "%s : task %zu does not fit in the context window\n", __func__, i0);
return;
}
llama_kv_cache_clear(ctx);
// decode all tasks [i0, i1)
if (!decode_helper(ctx, batch, batch_logits, n_batch, n_vocab)) {
fprintf(stderr, "%s: llama_decode() failed\n", __func__);
return;
}
eval_pairs.clear();
for (size_t i = i0; i < i1; ++i) {
auto & task = data[i];
const bool skip_choice =
task.seq_tokens[0].size() - task.common_prefix > k_min_trailing_ctx &&
task.seq_tokens[1].size() - task.common_prefix > k_min_trailing_ctx;
const auto& n_base1 = skip_choice ? task.n_base1 : task.common_prefix;
const int last_1st = task.seq_tokens[0].size() - n_base1 > 1 ? 1 : 0;
size_t li = n_base1 - 1;
for (size_t j = n_base1-1; j < task.seq_tokens[0].size()-1-last_1st; ++j) {
eval_pairs.emplace_back(task.i_batch + li++, task.seq_tokens[0][j+1]);
}
const auto& n_base2 = skip_choice ? task.n_base2 : task.common_prefix;
const int last_2nd = task.seq_tokens[1].size() - n_base2 > 1 ? 1 : 0;
li = task.seq_tokens[0].size() - task.common_prefix + n_base2 - 1;
for (size_t j = n_base2-1; j < task.seq_tokens[1].size()-1-last_2nd; ++j) {
eval_pairs.emplace_back(task.i_batch + li++, task.seq_tokens[1][j+1]);
}
}
compute_logprobs(batch_logits.data(), n_vocab, workers, eval_pairs, eval_results);
size_t ir = 0;
for (size_t i = i0; i < i1; ++i) {
auto & task = data[i];
const bool skip_choice =
task.seq_tokens[0].size() - task.common_prefix > k_min_trailing_ctx &&
task.seq_tokens[1].size() - task.common_prefix > k_min_trailing_ctx;
float score_1st = 0;
const auto& n_base1 = skip_choice ? task.n_base1 : task.common_prefix;
const int last_1st = task.seq_tokens[0].size() - n_base1 > 1 ? 1 : 0;
for (size_t j = n_base1-1; j < task.seq_tokens[0].size()-1-last_1st; ++j) {
score_1st += eval_results[ir++];
}
score_1st /= (task.seq_tokens[0].size() - n_base1 - last_1st);
float score_2nd = 0;
const auto& n_base2 = skip_choice ? task.n_base2 : task.common_prefix;
const int last_2nd = task.seq_tokens[1].size() - n_base2 > 1 ? 1 : 0;
for (size_t j = n_base2-1; j < task.seq_tokens[1].size()-1-last_2nd; ++j) {
score_2nd += eval_results[ir++];
}
score_2nd /= (task.seq_tokens[1].size() - n_base2 - last_2nd);
int result = score_1st > score_2nd ? 1 : 2;
if (result == task.answer) {
++n_correct;
}
++n_done;
// print the accumulated accuracy mean x 100
printf("%zu\t%.4lf\t%10.6f %10.6f %d %d\n", i+1, 100.0 * n_correct/n_done, score_1st, score_2nd, result, task.answer);
fflush(stdout);
}
i0 = i1 - 1;
}
printf("\n");
if (n_done < 100) return;
const float p = 1.f*n_correct/n_done;
const float sigma = 100.f*sqrt(p*(1-p)/(n_done-1));
printf("Final Winogrande score(%d tasks): %.4lf +/- %.4lf\n", n_done, 100*p, sigma);
}
static bool deserialize_string(std::istream & in, std::string & str) {
uint32_t size;
if (!in.read((char *)&size, sizeof(size)).fail()) {
str.resize(size);
if (!in.read((char *)&str[0], size).fail()) return true;
}
return false;
}
struct multiple_choice_answers {
std::vector<std::string> answers;
std::vector<int> labels;
bool deserialize(std::istream& in) {
uint32_t n;
in.read((char *)&n, sizeof(n));
if (in.fail() || n > 100) return false; // 100 as max. number of answers should be good enough for any practical purpose
answers.resize(n);
labels.resize(n);
for (auto& a : answers) {
if (!deserialize_string(in, a)) return false;
}
in.read((char *)labels.data(), n*sizeof(int));
return !in.fail();
}
};
struct multiple_choice_task {
std::string question; // the question (or context that needs to be continued)
multiple_choice_answers mc1; // possible answers (continuations) with a single correct answer
multiple_choice_answers mc2; // possible answers (continuations) with multiple correct answers - not handled yet
bool deserialize(std::istream& in) {
if (!deserialize_string(in, question)) return false;
return mc1.deserialize(in) && mc2.deserialize(in);
}
// For evaluation
size_t i_batch; // starting index in the llama_batch
size_t common_prefix; // max number of initial tokens that are the same in all sentences
size_t required_tokens; // needed number of tokens to evaluate all answers
std::vector<std::vector<llama_token>> seq_tokens;
std::vector<float> log_probs;
};
static bool multiple_choice_prepare_one_task(llama_context * ctx, bool add_bos, multiple_choice_task& task, bool log_error) {
if (task.question.empty() || task.mc1.answers.empty()) {
if (log_error) {
printf("%s: found bad task with empty question and/or answers\n", __func__);
}
return false;
}
task.seq_tokens.reserve(task.mc1.answers.size());
for (auto& answer : task.mc1.answers) {
if (answer.empty()) {
if (log_error) {
printf("%s: found empty answer\n", __func__);
}
return false;
}
task.seq_tokens.emplace_back(::llama_tokenize(ctx, task.question + " " + answer, add_bos));
}
auto min_len = task.seq_tokens.front().size();
for (auto& seq : task.seq_tokens) {
min_len = std::min(min_len, seq.size());
}
task.common_prefix = 0;
for (size_t k = 0; k < min_len; ++k) {
auto token = task.seq_tokens[0][k];
bool all_same = true;
for (size_t i = 1; i < task.seq_tokens.size(); ++i) {
if (task.seq_tokens[i][k] != token) {
all_same = false;
break;
}
}
if (!all_same) {
break;
}
++task.common_prefix;
}
task.required_tokens = task.common_prefix;
for (auto& seq : task.seq_tokens) {
task.required_tokens += seq.size() - task.common_prefix;
}
return true;
}
//
// Calculates score for multiple choice tasks with single correct answer from prompt.
// Commonly used LLM evaluation metrics of this type are
// * ARC
// * HellaSwag
// * MMLU
// * TruthfulQA
//
// Validation datasets for these 4 tests can be found at
// https://huggingface.co/datasets/ikawrakow/validation-datasets-for-llama.cpp
// The data for these datasets was extracted from
// git@hf.co:datasets/allenai/ai2_arc
// https://github.com/rowanz/hellaswag/blob/master/data/hellaswag_val.jsonl
// git@hf.co:datasets/Stevross/mmlu
// https://huggingface.co/datasets/truthful_qa
//
static void multiple_choice_score(llama_context * ctx, const gpt_params & params) {
std::istringstream strstream(params.prompt);
uint32_t n_task;
strstream.read((char *)&n_task, sizeof(n_task));
if (strstream.fail() || n_task == 0) {
printf("%s: no tasks\n", __func__);
return;
}
printf("%s: there are %u tasks in prompt\n", __func__, n_task);
std::vector<uint32_t> task_pos(n_task);
strstream.read((char *)task_pos.data(), task_pos.size()*sizeof(uint32_t));
if (strstream.fail()) {
printf("%s: failed to raad task positions from prompt\n", __func__);
return;
}
std::vector<multiple_choice_task> tasks;
if (params.multiple_choice_tasks == 0 || params.multiple_choice_tasks >= (size_t)n_task) {
// Use all tasks
tasks.resize(n_task);
printf("%s: reading tasks", __func__);
int n_dot = n_task/100;
int i = 0;
for (auto& task : tasks) {
++i;
if (!task.deserialize(strstream)) {
printf("%s: failed to read task %d of %u\n", __func__, i, n_task);
return;
}
if (i%n_dot == 0) printf(".");
}
printf("done\n");
}
else {
printf("%s: selecting %zu random tasks from %u tasks available\n", __func__, params.multiple_choice_tasks, n_task);
std::mt19937 rng(1);
std::vector<int> aux(n_task);
for (uint32_t i = 0; i < n_task; ++i) aux[i] = i;
float scale = 1.f/(1.f + (float)std::mt19937::max());
tasks.resize(params.multiple_choice_tasks);
for (auto& task : tasks) {
int j = (int)(scale * rng() * aux.size());
int idx = aux[j];
aux[j] = aux.back();
aux.pop_back();
strstream.seekg(task_pos[idx], std::ios::beg);
if (!task.deserialize(strstream)) {
printf("%s: failed to read task %d at position %u\n", __func__, idx, task_pos[idx]);
return;
}
}
n_task = params.multiple_choice_tasks;
}
// This is needed as usual for LLaMA models
const bool add_bos = llama_should_add_bos_token(llama_get_model(ctx));
printf("%s: preparing task data", __func__);
fflush(stdout);
if (n_task > 500) {
printf("...");
fflush(stdout);
std::atomic<int> counter(0);
std::atomic<int> n_bad(0);
auto prepare = [&counter, &n_bad, &tasks, ctx, add_bos] () {
int num_tasks = tasks.size();
int n_bad_local = 0;
while (true) {
int first = counter.fetch_add(K_TOKEN_CHUNK);
if (first >= num_tasks) {
if (n_bad_local > 0) n_bad += n_bad_local;
break;
}
int last = std::min(first + K_TOKEN_CHUNK, num_tasks);
for (int i = first; i < last; ++i) {
if (!multiple_choice_prepare_one_task(ctx, add_bos, tasks[i], false)) ++n_bad_local;
}
}
};
size_t max_thread = std::thread::hardware_concurrency();
max_thread = std::min(max_thread, (tasks.size() + K_TOKEN_CHUNK - 1)/K_TOKEN_CHUNK);
std::vector<std::thread> workers(max_thread-1);
for (auto& w : workers) w = std::thread(prepare);
prepare();
for (auto& w : workers) w.join();
printf("done\n");
fflush(stdout);
int nbad = n_bad;
if (nbad > 0) {
printf("%s: found %d malformed tasks\n", __func__, nbad);
return;
}
} else {
int n_dot = n_task/100;
int i_task = 0;
for (auto& task : tasks) {
++i_task;
if (!multiple_choice_prepare_one_task(ctx, add_bos, task, true)) {
return;
}
if (i_task%n_dot == 0) {
printf(".");
fflush(stdout);
}
}
printf("done\n");
}
printf("%s : calculating TruthfulQA score over %zu tasks.\n", __func__, tasks.size());
printf("\ntask\tacc_norm\n");
const int n_vocab = llama_n_vocab(llama_get_model(ctx));
const int n_ctx = llama_n_ctx(ctx);
const int n_batch = params.n_batch;
const int max_tasks_per_batch = 32;
const int max_seq = 4*max_tasks_per_batch;
llama_batch batch = llama_batch_init(n_ctx, 0, max_seq);
std::vector<float> tok_logits(n_vocab);
std::vector<float> batch_logits(n_vocab*n_ctx);
std::vector<std::pair<size_t, llama_token>> eval_pairs;
std::vector<float> eval_results;
std::vector<std::thread> workers(std::thread::hardware_concurrency());
std::vector<int> batch_indeces;
int n_done = 0;
int n_correct = 0;
int n_tot_answers = 0;
for (size_t i0 = 0; i0 < tasks.size(); i0++) {
int n_cur = 0;
size_t i1 = i0;
size_t i_batch = 0; // this tells us where in `llama_batch` we are currently
llama_batch_clear(batch);
// batch as much tasks as possible into the available context
// each task has 4 unique seuqnce ids - one for each ending
// the common prefix is shared among the 4 sequences to save tokens
// we extract logits only from the last common token and from all ending tokens of each sequence
int s0 = 0;
while (n_cur + (int) tasks[i1].required_tokens <= n_ctx) {
auto& cur_task = tasks[i1];
int num_answers = cur_task.seq_tokens.size();
if (s0 + num_answers > max_seq) {
break;
}
if (int(batch_indeces.size()) != num_answers) {
batch_indeces.resize(num_answers);
}
for (int s = 0; s < num_answers; ++s) batch_indeces[s] = s0 + s;
for (size_t i = 0; i < cur_task.common_prefix; ++i) {
//llama_batch_add(batch, cur_task.seq_tokens[0][i], i, { s0 + 0, s0 + 1, s0 + 2, s0 + 3}, false);
llama_batch_add(batch, cur_task.seq_tokens[0][i], i, batch_indeces, false);
}
batch.logits[batch.n_tokens - 1] = true; // we need logits for the last token of the common prefix
for (int s = 0; s < int(cur_task.seq_tokens.size()); ++s) {
for (size_t i = cur_task.common_prefix; i < cur_task.seq_tokens[s].size(); ++i) {
llama_batch_add(batch, cur_task.seq_tokens[s][i], i, { s0 + s }, true);
}
}
s0 += num_answers;
cur_task.i_batch = i_batch;
i_batch += cur_task.required_tokens;
n_cur += cur_task.required_tokens;
if (++i1 == tasks.size()) {
break;
}
}
if (i0 == i1) {
fprintf(stderr, "%s : task %zu does not fit in the context window\n", __func__, i0);
return;
}
llama_kv_cache_clear(ctx);
// decode all tasks [i0, i1)
if (!decode_helper(ctx, batch, batch_logits, n_batch, n_vocab)) {
fprintf(stderr, "%s: llama_decode() failed\n", __func__);
return;
}
// Compute log-probs in parallel
// First we collect all tasks
eval_pairs.clear();
for (size_t i = i0; i < i1; ++i) {
auto& cur_task = tasks[i];
size_t li = cur_task.common_prefix;
for (int s = 0; s < int(cur_task.seq_tokens.size()); ++s) {
for (size_t j = cur_task.common_prefix; j < cur_task.seq_tokens[s].size() - 1; j++) {
eval_pairs.emplace_back(cur_task.i_batch + li++, cur_task.seq_tokens[s][j + 1]);
}
++li;
}
}
// Then we do the actual calculation
compute_logprobs(batch_logits.data(), n_vocab, workers, eval_pairs, eval_results);
size_t ir = 0;
// compute the logprobs for each ending of the decoded tasks
for (size_t i = i0; i < i1; ++i) {
auto & cur_task = tasks[i];
//printf("==== Evaluating <%s> with correct answer ", cur_task.question.c_str());
//for (int j = 0; j < int(cur_task.mc1.labels.size()); ++j) {
// if (cur_task.mc1.labels[j] == 1) {
// printf("%d", j+1);
// }
//}
//printf("\n common_prefix: %zu\n", cur_task.common_prefix);
std::memcpy(tok_logits.data(), batch_logits.data() + n_vocab*(cur_task.i_batch + cur_task.common_prefix - 1), n_vocab*sizeof(float));
const auto first_probs = softmax(tok_logits);
cur_task.log_probs.resize(cur_task.seq_tokens.size());
for (int s = 0; s < int(cur_task.seq_tokens.size()); ++s) {
size_t count = 1;
float log_prob = std::log(first_probs[cur_task.seq_tokens[s][cur_task.common_prefix]]);
for (size_t j = cur_task.common_prefix; j < cur_task.seq_tokens[s].size() - 1; j++) {
//printf(" %zu %g\n", ir, eval_results[ir]);
++count;
log_prob += eval_results[ir++];
}
cur_task.log_probs[s] = log_prob / count;
//printf(" Final: %g\n", log_prob / count);
//printf(" <%s> : %g\n", cur_task.mc1.answers[s].c_str(), log_prob/count);
}
// Find the ending with maximum logprob
size_t logprob_max_idx = 0;
float logprob_max_val = cur_task.log_probs[0];
for (size_t s = 1; s < cur_task.log_probs.size(); s++) {
if (cur_task.log_probs[s] > logprob_max_val) {
logprob_max_val = cur_task.log_probs[s];
logprob_max_idx = s;
}
}
n_tot_answers += cur_task.log_probs.size();
if (cur_task.mc1.labels[logprob_max_idx] == 1) {
++n_correct;
}
++n_done;
// Print the accumulated accuracy mean x 100
printf("%d\t%.8lf\n", n_done, 100.*n_correct/n_done);
fflush(stdout);
}
i0 = i1 - 1;
}
llama_batch_free(batch);
if (n_done < 100) return;
float p = 1.f*n_correct/n_done;
float sigma = sqrt(p*(1-p)/(n_done-1));
printf("\n Final result: %.4f +/- %.4f\n", 100.f*p, 100.f*sigma);
p = 1.f*n_done/n_tot_answers;
sigma = sqrt(p*(1-p)/(n_done-1));
printf("Random chance: %.4f +/- %.4f\n", 100.f*p, 100.f*sigma);
printf("\n");
}
static void kl_divergence(llama_context * ctx, const gpt_params & params) {
if (params.logits_file.empty()) {
fprintf(stderr, "%s: you must provide a name of a file containing the log probabilities of the base model\n", __func__);
return;
}
std::ifstream in(params.logits_file.c_str(), std::ios::binary);
if (!in) {
fprintf(stderr, "%s: failed to open %s\n", __func__, params.logits_file.c_str());
return;
}
{
char check[9]; check[8] = 0;
in.read(check, 8);
if (in.fail() || strncmp("_logits_", check, 8) != 0) {
fprintf(stderr, "%s: %s does not look like a file containing log-probabilities\n", __func__, params.logits_file.c_str());
return;
}
}
uint32_t n_ctx;
in.read((char *)&n_ctx, sizeof(n_ctx));
if (n_ctx > llama_n_ctx(ctx)) {
fprintf(stderr, "%s: %s has been computed with %u, while the current context is %d. Increase it with -c and retry\n",
__func__, params.logits_file.c_str(), n_ctx, params.n_ctx);
}
int n_vocab, n_chunk;
in.read((char *)&n_vocab, sizeof(n_vocab));
in.read((char *)&n_chunk, sizeof(n_chunk));
if (in.fail()) {
fprintf(stderr, "%s: failed reading n_vocab, n_chunk from %s\n", __func__, params.logits_file.c_str());
return;
}
if (n_vocab != llama_n_vocab(llama_get_model(ctx))) {
fprintf(stderr, "%s: inconsistent vocabulary (%d vs %d)\n", __func__, n_vocab, llama_n_vocab(llama_get_model(ctx)));
}
std::vector<llama_token> tokens(n_ctx * n_chunk);
if (in.read((char *)tokens.data(), tokens.size()*sizeof(tokens[0])).fail()) {
fprintf(stderr, "%s: failed reading evaluation tokens from %s\n", __func__, params.logits_file.c_str());
return;
}
const int n_batch = params.n_batch;
const int num_batches = (n_ctx + n_batch - 1)/n_batch;
const int nv = 2*((n_vocab + 1)/2) + 4;
const bool add_bos = llama_should_add_bos_token(llama_get_model(ctx));
std::vector<uint16_t> log_probs_uint16(size_t(n_ctx - 1 - n_ctx/2) * nv);
std::vector<float> kld_values(size_t(n_ctx - 1 - n_ctx/2)*n_chunk);
std::vector<float> logits;
if (num_batches > 1) {
logits.reserve(n_ctx * n_vocab);
}
std::vector<std::thread> workers(std::thread::hardware_concurrency() - 1);
auto mean_and_uncertainty = [] (double sum, double sum2, size_t count) {
if (count < 1) {
return std::make_pair(0., 0.);
}
double f = sum/count;
double df = sum2/count - f*f;
df = df > 0 && count > 10 ? sqrt(df/(count-1)) : 0.;
return std::make_pair(f, df);
};
kl_divergence_result kld;
auto kld_ptr = kld_values.data();
for (int i = 0; i < n_chunk; ++i) {
const int start = i * n_ctx;
const int end = start + n_ctx;
const auto t_start = std::chrono::high_resolution_clock::now();
if (in.read((char *)log_probs_uint16.data(), log_probs_uint16.size()*sizeof(uint16_t)).fail()) {
fprintf(stderr, "%s: failed reading log-probs for chunk %d\n", __func__, i);
return;
}
// clear the KV cache
llama_kv_cache_clear(ctx);
for (int j = 0; j < num_batches; ++j) {
const int batch_start = start + j * n_batch;
const int batch_size = std::min(end - batch_start, n_batch);
// save original token and restore it after eval
const auto token_org = tokens[batch_start];
// add BOS token for the first batch of each chunk
if (add_bos && j == 0) {
tokens[batch_start] = llama_token_bos(llama_get_model(ctx));
}
if (llama_decode(ctx, llama_batch_get_one(tokens.data() + batch_start, batch_size, j * n_batch, 0))) {
fprintf(stderr, "%s : failed to eval\n", __func__);
return;
}
// restore the original token in case it was set to BOS
tokens[batch_start] = token_org;
if (num_batches > 1) {
const auto * batch_logits = llama_get_logits(ctx);
logits.insert(logits.end(), batch_logits, batch_logits + batch_size * n_vocab);
}
}
const auto t_end = std::chrono::high_resolution_clock::now();
if (i == 0) {
const float t_total = std::chrono::duration<float>(t_end - t_start).count();
fprintf(stderr, "%s: %.2f seconds per pass - ETA ", __func__, t_total);
int total_seconds = (int)(t_total * n_chunk);
if (total_seconds >= 60*60) {
fprintf(stderr, "%d hours ", total_seconds / (60*60));
total_seconds = total_seconds % (60*60);
}
fprintf(stderr, "%.2f minutes\n", total_seconds / 60.0);
printf("\nchunk PPL ln(PPL(Q)/PPL(base)) KL-Divergence Same top\n");
}
const int first = n_ctx/2;
const float * all_logits = num_batches > 1 ? logits.data() : llama_get_logits(ctx);
process_logits(n_vocab, all_logits + first*n_vocab, tokens.data() + start + first, n_ctx - 1 - first,
workers, log_probs_uint16, kld, kld_ptr);
kld_ptr += n_ctx - 1 - first;
auto ppl = mean_and_uncertainty(kld.sum_nll, kld.sum_nll2, kld.count);
auto log_ppl_ratio = mean_and_uncertainty(kld.sum_nll_diff, kld.sum_nll_diff2, kld.count);
auto kl_div = mean_and_uncertainty(kld.sum_kld, kld.sum_kld2, kld.count);
auto p_top = 1.*kld.n_same_top/kld.count;
auto d_p_top = sqrt(p_top*(1 - p_top)/(kld.count - 1));
printf("%4d %10.4lf %10.5lf ± %10.5f %10.5f ± %10.5lf %.5f ± %.5f\n", i+1, exp(ppl.first),
log_ppl_ratio.first, log_ppl_ratio.second, kl_div.first, kl_div.second,
p_top, d_p_top);
fflush(stdout);
logits.clear();
}
printf("\n");
if (kld.count < 100) return; // we do not wish to do statistics on so few values
std::sort(kld_values.begin(), kld_values.end());
printf("===== KL-divergence statistics\n");
auto kl_div = mean_and_uncertainty(kld.sum_kld, kld.sum_kld2, kld.count);
printf("Average: %10.6f ±%10.6lf\n", kl_div.first, kl_div.second);
auto kld_median = kld_values.size()%2 == 0 ? 0.5f*(kld_values[kld_values.size()/2] + kld_values[kld_values.size()/2-1])
: kld_values[kld_values.size()/2];
printf("Median : %10.6f\n", kld_median);
auto percentile = [&kld_values] (float fraction) {
if (fraction <= 0) return kld_values.front();
if (fraction >= 1) return kld_values.back();
float p = fraction*(kld_values.size() - 1);
size_t ip = size_t(p); p -= ip;
return (1 - p)*kld_values[ip] + p*kld_values[std::min(ip+1, kld_values.size()-1)];
};
printf("Maximum: %10.6f\n", kld_values.back());
printf("KLD_99 : %10.6f\n", percentile(0.99f));
printf("KLD_95 : %10.6f\n", percentile(0.95f));
printf("KLD_90 : %10.6f\n", percentile(0.90f));
printf("Minimum: %10.6f\n", kld_values.front());
printf("KLD_01 : %10.6f\n", percentile(0.01f));
printf("KLD_05 : %10.6f\n", percentile(0.05f));
printf("KLD_10 : %10.6f\n", percentile(0.10f));
}
int main(int argc, char ** argv) {
gpt_params params;
params.n_batch = 512;
if (!gpt_params_parse(argc, argv, params)) {
return 1;
}
params.logits_all = true;
params.n_batch = std::min(params.n_batch, params.n_ctx);
if (params.ppl_stride > 0) {
fprintf(stderr, "Will perform strided perplexity calculation -> adjusting context size from %d to %d\n",
params.n_ctx, params.n_ctx + params.ppl_stride/2);
params.n_ctx += params.ppl_stride/2;
}
print_build_info();
if (params.seed == LLAMA_DEFAULT_SEED) {
params.seed = time(NULL);
}
fprintf(stderr, "%s: seed = %u\n", __func__, params.seed);
std::mt19937 rng(params.seed);
if (params.random_prompt) {
params.prompt = gpt_random_prompt(rng);
}
llama_backend_init();
llama_numa_init(params.numa);
llama_model * model;
llama_context * ctx;
// load the model and apply lora adapter, if any
std::tie(model, ctx) = llama_init_from_gpt_params(params);
if (model == NULL) {
fprintf(stderr, "%s: error: unable to load model\n", __func__);
return 1;
}
const int n_ctx_train = llama_n_ctx_train(model);
if (params.n_ctx > n_ctx_train) {
fprintf(stderr, "%s: warning: model was trained on only %d context tokens (%d specified)\n",
__func__, n_ctx_train, params.n_ctx);
}
// print system information
{
fprintf(stderr, "\n");
fprintf(stderr, "%s\n", get_system_info(params).c_str());
}
struct results_perplexity results;
if (params.hellaswag) {
hellaswag_score(ctx, params);
} else if (params.winogrande) {
winogrande_score(ctx, params);
} else if (params.multiple_choice) {
multiple_choice_score(ctx, params);
} else if (params.kl_divergence) {
kl_divergence(ctx, params);
} else {
results = perplexity(ctx, params);
}
llama_print_timings(ctx);
write_logfile(ctx, params, model, results);
llama_free(ctx);
llama_free_model(model);
llama_backend_free();
return 0;
}