From a8c981b7340f4a9ce62d9086f35c70af5406913b Mon Sep 17 00:00:00 2001
From: Georgi Gerganov <ggerganov@gmail.com>
Date: Thu, 19 Oct 2023 14:10:37 +0300
Subject: [PATCH] server : remove beam-search functionality

---
 examples/server/server.cpp | 77 +++++---------------------------------
 1 file changed, 9 insertions(+), 68 deletions(-)

diff --git a/examples/server/server.cpp b/examples/server/server.cpp
index ab1b5fbd3..746971520 100644
--- a/examples/server/server.cpp
+++ b/examples/server/server.cpp
@@ -1296,12 +1296,6 @@ struct llama_server_context
     }
 };
 
-struct server_beam_search_callback_data
-{
-    llama_context * ctx;
-    llama_client_slot * slot;
-};
-
 static void server_print_usage(const char *argv0, const gpt_params &params,
                                const server_params &sparams)
 {
@@ -2006,46 +2000,6 @@ static void log_server_request(const httplib::Request &req, const httplib::Respo
                            });
 }
 
-static bool is_at_eob(const server_beam_search_callback_data & server_context, const llama_token *tokens, const size_t n_tokens) {
-    return n_tokens && tokens[n_tokens - 1] == llama_token_eos(server_context.ctx);
-}
-
-// Function matching type llama_beam_search_callback_fn_t.
-// Custom callback example is called each time the beams lengths increase:
-//  * Show progress by printing ',' following by number of convergent beam tokens if any.
-//  * When all beams converge to a common prefix, they are made available in beams_state.beams[0].
-//    This is also called when the stop condition is met.
-//    Collect tokens into std::vector<llama_token> response which is pointed to by callback_data.
-
-// NO TESTED after PR #3589
-
-static void beam_search_callback(void *callback_data, llama_beams_state beams_state) {
-    auto & llama = *static_cast<server_beam_search_callback_data *>(callback_data);
-    // Mark beams as EOS as needed.
-    for (size_t i = 0 ; i < beams_state.n_beams ; ++i) {
-        llama_beam_view& beam_view = beams_state.beam_views[i];
-        if (!beam_view.eob && is_at_eob(llama, beam_view.tokens, beam_view.n_tokens)) {
-            beam_view.eob = true;
-        }
-    }
-    printf(",");  // Show progress
-    if (const size_t n = beams_state.common_prefix_length) {
-        llama.slot->generated_token_probs.resize(llama.slot->generated_token_probs.size() + n);
-        assert(0u < beams_state.n_beams);
-        const llama_token * tokens = beams_state.beam_views[0].tokens;
-        const auto map = [](llama_token tok) { return completion_token_output{{},tok,""}; };
-        std::transform(tokens, tokens + n, llama.slot->generated_token_probs.end() - n, map);
-        printf("%zu", n);
-    }
-    fflush(stdout);
-#if 0 // DEBUG: print current beams for this iteration
-    std::cout << "\n\nCurrent beams:\n";
-    for (size_t i=0 ; i < beams_state.n_beams ; ++i) {
-        std::cout << "beams["<<i<<"]: " << ostream_beam_view{state.ctx,beams_state.beam_views[i]} << std::endl;
-    }
-#endif
-}
-
 struct token_translator
 {
     llama_context * ctx;
@@ -2176,30 +2130,17 @@ int main(int argc, char **argv)
                 }
 
                 if (!slot->params.stream) {
-                    std::string completion_text = "";
-                    if (llama.params.n_beams)
+                    std::string completion_text;
+
+                    while (slot->is_processing())
                     {
-                        // Fill llama.generated_token_probs vector with final beam.
-                        server_beam_search_callback_data data_beam;
-                        data_beam.slot = slot;
-                        data_beam.ctx = llama.ctx;
-                        llama_beam_search(llama.ctx, beam_search_callback, &data_beam, llama.params.n_beams,
-                                slot->n_past, llama.params.n_predict);
-                        // Translate llama.generated_token_probs to llama.generated_text.
-                        append_to_generated_text_from_generated_token_probs(llama, slot);
-                    }
-                    else
-                    {
-                        while (slot->is_processing())
+                        if (slot->has_new_token())
                         {
-                            if (slot->has_new_token())
-                            {
-                                completion_text += slot->next().text_to_send;
-                            }
-                            else
-                            {
-                                std::this_thread::sleep_for(std::chrono::microseconds(5));
-                            }
+                            completion_text += slot->next().text_to_send;
+                        }
+                        else
+                        {
+                            std::this_thread::sleep_for(std::chrono::microseconds(5));
                         }
                     }