gpt4all/llmodel/llamamodel.cpp
Adam Treat f291853e51 First attempt at providing a persistent chat list experience.
Limitations:

1) Context is not restored for gpt-j models
2) When you switch between different model types in an existing chat
   the context and all the conversation is lost
3) The settings are not chat or conversation specific
4) The sizes of the chat persisted files are very large due to how much
   data the llama.cpp backend tries to persist. Need to investigate how
   we can shrink this.
2023-05-04 15:31:41 -04:00

261 lines
8.5 KiB
C++

#include "llamamodel.h"
#include "llama.cpp/examples/common.h"
#include "llama.cpp/llama.h"
#include "llama.cpp/ggml.h"
#include <cassert>
#include <cmath>
#include <cstdio>
#include <cstring>
#include <fstream>
#include <map>
#include <string>
#include <vector>
#include <iostream>
#include <unistd.h>
#include <random>
#include <thread>
#include <unordered_set>
struct LLamaPrivate {
const std::string modelPath;
bool modelLoaded;
llama_context *ctx = nullptr;
llama_context_params params;
int64_t n_threads = 0;
};
LLamaModel::LLamaModel()
: d_ptr(new LLamaPrivate) {
d_ptr->modelLoaded = false;
}
bool LLamaModel::loadModel(const std::string &modelPath)
{
// load the model
d_ptr->params = llama_context_default_params();
gpt_params params;
d_ptr->params.n_ctx = 2048;
d_ptr->params.n_parts = params.n_parts;
d_ptr->params.seed = params.seed;
d_ptr->params.f16_kv = params.memory_f16;
d_ptr->params.use_mmap = params.use_mmap;
d_ptr->params.use_mlock = params.use_mlock;
d_ptr->ctx = llama_init_from_file(modelPath.c_str(), d_ptr->params);
if (!d_ptr->ctx) {
std::cerr << "LLAMA ERROR: failed to load model from " << modelPath << std::endl;
return false;
}
d_ptr->n_threads = std::min(4, (int32_t) std::thread::hardware_concurrency());
d_ptr->modelLoaded = true;
fflush(stderr);
return true;
}
void LLamaModel::setThreadCount(int32_t n_threads) {
d_ptr->n_threads = n_threads;
}
int32_t LLamaModel::threadCount() {
return d_ptr->n_threads;
}
LLamaModel::~LLamaModel()
{
llama_free(d_ptr->ctx);
}
bool LLamaModel::isModelLoaded() const
{
return d_ptr->modelLoaded;
}
size_t LLamaModel::stateSize() const
{
return llama_get_state_size(d_ptr->ctx);
}
size_t LLamaModel::saveState(uint8_t *dest) const
{
return llama_copy_state_data(d_ptr->ctx, dest);
}
size_t LLamaModel::restoreState(const uint8_t *src)
{
return llama_set_state_data(d_ptr->ctx, src);
}
void LLamaModel::prompt(const std::string &prompt,
std::function<bool(int32_t)> promptCallback,
std::function<bool(int32_t, const std::string&)> responseCallback,
std::function<bool(bool)> recalculateCallback,
PromptContext &promptCtx) {
if (!isModelLoaded()) {
std::cerr << "LLAMA ERROR: prompt won't work with an unloaded model!\n";
return;
}
gpt_params params;
params.prompt = prompt;
// Add a space in front of the first character to match OG llama tokenizer behavior
params.prompt.insert(0, 1, ' ');
// tokenize the prompt
auto embd_inp = ::llama_tokenize(d_ptr->ctx, params.prompt, false);
// save the context size
promptCtx.n_ctx = llama_n_ctx(d_ptr->ctx);
if ((int) embd_inp.size() > promptCtx.n_ctx - 4) {
responseCallback(-1, "The prompt size exceeds the context window size and cannot be processed.");
std::cerr << "LLAMA ERROR: The prompt is" << embd_inp.size() <<
"tokens and the context window is" << promptCtx.n_ctx << "!\n";
return;
}
promptCtx.n_predict = std::min(promptCtx.n_predict, promptCtx.n_ctx - (int) embd_inp.size());
promptCtx.n_past = std::min(promptCtx.n_past, promptCtx.n_ctx);
// number of tokens to keep when resetting context
params.n_keep = (int)embd_inp.size();
// process the prompt in batches
size_t i = 0;
const int64_t t_start_prompt_us = ggml_time_us();
while (i < embd_inp.size()) {
size_t batch_end = std::min(i + promptCtx.n_batch, embd_inp.size());
std::vector<llama_token> batch(embd_inp.begin() + i, embd_inp.begin() + batch_end);
// Check if the context has run out...
if (promptCtx.n_past + batch.size() > promptCtx.n_ctx) {
const int32_t erasePoint = promptCtx.n_ctx * promptCtx.contextErase;
// Erase the first percentage of context from the tokens...
std::cerr << "LLAMA: reached the end of the context window so resizing\n";
promptCtx.tokens.erase(promptCtx.tokens.begin(), promptCtx.tokens.begin() + erasePoint);
promptCtx.n_past = promptCtx.tokens.size();
recalculateContext(promptCtx, recalculateCallback);
assert(promptCtx.n_past + batch.size() <= promptCtx.n_ctx);
}
if (llama_eval(d_ptr->ctx, batch.data(), batch.size(), promptCtx.n_past, d_ptr->n_threads)) {
std::cerr << "LLAMA ERROR: Failed to process prompt\n";
return;
}
size_t tokens = batch_end - i;
for (size_t t = 0; t < tokens; ++t) {
if (promptCtx.tokens.size() == promptCtx.n_ctx)
promptCtx.tokens.erase(promptCtx.tokens.begin());
promptCtx.tokens.push_back(batch.at(t));
if (!promptCallback(batch.at(t)))
return;
}
promptCtx.n_past += batch.size();
i = batch_end;
}
std::string cachedResponse;
std::vector<llama_token> cachedTokens;
std::unordered_set<std::string> reversePrompts
= { "### Instruction", "### Prompt", "### Response", "### Human", "### Assistant" };
// predict next tokens
int32_t totalPredictions = 0;
for (int i = 0; i < promptCtx.n_predict; i++) {
// sample next token
llama_token id = llama_sample_top_p_top_k(d_ptr->ctx,
promptCtx.tokens.data() + promptCtx.n_ctx - promptCtx.repeat_last_n,
promptCtx.repeat_last_n, promptCtx.top_k, promptCtx.top_p, promptCtx.temp,
promptCtx.repeat_penalty);
// Check if the context has run out...
if (promptCtx.n_past + 1 > promptCtx.n_ctx) {
const int32_t erasePoint = promptCtx.n_ctx * promptCtx.contextErase;
// Erase the first percentage of context from the tokens...
std::cerr << "LLAMA: reached the end of the context window so resizing\n";
promptCtx.tokens.erase(promptCtx.tokens.begin(), promptCtx.tokens.begin() + erasePoint);
promptCtx.n_past = promptCtx.tokens.size();
recalculateContext(promptCtx, recalculateCallback);
assert(promptCtx.n_past + 1 <= promptCtx.n_ctx);
}
if (llama_eval(d_ptr->ctx, &id, 1, promptCtx.n_past, d_ptr->n_threads)) {
std::cerr << "LLAMA ERROR: Failed to predict next token\n";
return;
}
promptCtx.n_past += 1;
// display text
++totalPredictions;
if (id == llama_token_eos())
return;
const std::string str = llama_token_to_str(d_ptr->ctx, id);
// Check if the provided str is part of our reverse prompts
bool foundPartialReversePrompt = false;
const std::string completed = cachedResponse + str;
if (reversePrompts.find(completed) != reversePrompts.end()) {
return;
}
// Check if it partially matches our reverse prompts and if so, cache
for (auto s : reversePrompts) {
if (s.compare(0, completed.size(), completed) == 0) {
foundPartialReversePrompt = true;
cachedResponse = completed;
break;
}
}
// Regardless the token gets added to our cache
cachedTokens.push_back(id);
// Continue if we have found a partial match
if (foundPartialReversePrompt)
continue;
// Empty the cache
for (auto t : cachedTokens) {
if (promptCtx.tokens.size() == promptCtx.n_ctx)
promptCtx.tokens.erase(promptCtx.tokens.begin());
promptCtx.tokens.push_back(t);
if (!responseCallback(t, llama_token_to_str(d_ptr->ctx, t)))
return;
}
cachedTokens.clear();
}
}
void LLamaModel::recalculateContext(PromptContext &promptCtx, std::function<bool(bool)> recalculate)
{
size_t i = 0;
promptCtx.n_past = 0;
while (i < promptCtx.tokens.size()) {
size_t batch_end = std::min(i + promptCtx.n_batch, promptCtx.tokens.size());
std::vector<llama_token> batch(promptCtx.tokens.begin() + i, promptCtx.tokens.begin() + batch_end);
assert(promptCtx.n_past + batch.size() <= promptCtx.n_ctx);
if (llama_eval(d_ptr->ctx, batch.data(), batch.size(), promptCtx.n_past, d_ptr->n_threads)) {
std::cerr << "LLAMA ERROR: Failed to process prompt\n";
goto stop_generating;
}
promptCtx.n_past += batch.size();
if (!recalculate(true))
goto stop_generating;
i = batch_end;
}
assert(promptCtx.n_past == promptCtx.tokens.size());
stop_generating:
recalculate(false);
}