Bump llama.cpp to b1999

This requires an upstream change to support graceful termination,
carried as a patch.

llm/ext_server/ext_server.cpp

@@ -26,13 +26,13 @@
 
 // Expose the llama server as a callable extern "C" API
 llama_server_context *llama = NULL;
-std::atomic<bool> ext_server_running(false);
 std::thread ext_server_thread;
 
 void llama_server_init(ext_server_params *sparams, ext_server_resp_t *err) {
   assert(err != NULL && sparams != NULL);
   log_set_target(stderr);
   if (!sparams->verbose_logging) {
+    server_verbose = true;
     log_disable();
   }
 
@@ -122,18 +122,23 @@ void llama_server_start() {
   assert(llama != NULL);
   // TODO mutex to protect thread creation
   ext_server_thread = std::thread([&]() {
-    ext_server_running = true;
     try {
       LOG_TEE("llama server main loop starting\n");
       ggml_time_init();
-      while (ext_server_running.load()) {
-        if (!llama->update_slots()) {
-          LOG_TEE(
-              "unexpected error in llama server update_slots - exiting main "
-              "loop\n");
-          break;
-        }
-      }
+      llama->queue_tasks.on_new_task(std::bind(
+        &llama_server_context::process_single_task, llama, std::placeholders::_1));
+      llama->queue_tasks.on_finish_multitask(std::bind(
+          &llama_server_context::on_finish_multitask, llama, std::placeholders::_1));
+      llama->queue_tasks.on_all_tasks_finished(std::bind(
+          &llama_server_context::run_on_all_tasks_finished, llama));
+      llama->queue_results.on_multitask_update(std::bind(
+          &llama_server_queue::update_multitask,
+          &llama->queue_tasks,
+          std::placeholders::_1,
+          std::placeholders::_2,
+          std::placeholders::_3
+        ));
+      llama->queue_tasks.start_loop();
     } catch (std::exception &e) {
       LOG_TEE("caught exception in llama server main loop: %s\n", e.what());
     } catch (...) {
@@ -146,13 +151,10 @@ void llama_server_start() {
 
 void llama_server_stop() {
   assert(llama != NULL);
-  // TODO - too verbose, remove once things are solid
-  LOG_TEE("requesting llama server shutdown\n");
-  ext_server_running = false;
-
-  // unblocks the update_slots() loop so it can clean up and exit
-  llama->request_cancel(0);
-
+  LOG_TEE("\ninitiating shutdown - draining remaining tasks...\n");
+  // This may take a while for any pending tasks to drain
+  // TODO - consider a timeout to cancel tasks if it's taking too long
+  llama->queue_tasks.terminate();
   ext_server_thread.join();
   delete llama;
   llama = NULL;
@@ -165,7 +167,9 @@ void llama_server_completion(const char *json_req, ext_server_resp_t *resp) {
   resp->msg[0] = '\0';
   try {
     json data = json::parse(json_req);
-    resp->id = llama->request_completion(data, false, false, -1);
+    resp->id = llama->queue_tasks.get_new_id();
+    llama->queue_results.add_waiting_task_id(resp->id);
+    llama->request_completion(resp->id, data, false, false, -1);
   } catch (std::exception &e) {
     snprintf(resp->msg, resp->msg_len, "exception %s", e.what());
   } catch (...) {
@@ -183,16 +187,22 @@ void llama_server_completion_next_result(const int task_id,
   resp->json_resp = NULL;
   std::string result_json;
   try {
-    task_result result = llama->next_result(task_id);
+    task_result result = llama->queue_results.recv(task_id);
     result_json =
         result.result_json.dump(-1, ' ', false, json::error_handler_t::replace);
     resp->id = result.id;
     resp->stop = result.stop;
     resp->error = result.error;
     if (result.error) {
+      LOG_TEE("next result cancel on error\n");
       llama->request_cancel(task_id);
+      LOG_TEE("next result removing waiting tak ID: %d\n", task_id);
+      llama->queue_results.remove_waiting_task_id(task_id);
     } else if (result.stop) {
+      LOG_TEE("next result cancel on stop\n");
       llama->request_cancel(task_id);
+      LOG_TEE("next result removing waiting task ID: %d\n", task_id);
+      llama->queue_results.remove_waiting_task_id(task_id);
     }
   } catch (std::exception &e) {
     resp->error = true;
@@ -223,6 +233,7 @@ void llama_server_completion_cancel(const int task_id, ext_server_resp_t *err) {
   err->msg[0] = '\0';
   try {
     llama->request_cancel(task_id);
+    llama->queue_results.remove_waiting_task_id(task_id);
   } catch (std::exception &e) {
     err->id = -1;
     snprintf(err->msg, err->msg_len, "exception %s", e.what());
@@ -307,13 +318,15 @@ void llama_server_embedding(const char *json_req, char **json_resp,
     } else {
       prompt = "";
     }
-    const int task_id = llama->request_completion(
-        {{"prompt", prompt}, {"n_predict", 0}}, false, true, -1);
-    task_result result = llama->next_result(task_id);
+    const int task_id = llama->queue_tasks.get_new_id();
+    llama->queue_results.add_waiting_task_id(task_id);
+    llama->request_completion(task_id, {{"prompt", prompt}, {"n_predict", 0}}, false, true, -1);
+    task_result result = llama->queue_results.recv(task_id);
     std::string result_json = result.result_json.dump();
     const std::string::size_type size = result_json.size() + 1;
     *json_resp = new char[size];
     snprintf(*json_resp, size, "%s", result_json.c_str());
+    llama->queue_results.remove_waiting_task_id(task_id);
   } catch (std::exception &e) {
     err->id = -1;
     snprintf(err->msg, err->msg_len, "exception %s", e.what());

llm/llama.cpp

@@ -1 +1 @@
-Subproject commit cd4fddb29f81d6a1f6d51a0c016bc6b486d68def
+Subproject commit d2f650cb5b04ee2726663e79b47da5efe196ce00

llm/patches/01-cache.diff

@@ -1,8 +1,8 @@
 diff --git a/examples/server/server.cpp b/examples/server/server.cpp
-index 0462fbd2..4fa7b57f 100644
+index a48582ad..9fffffd8 100644
 --- a/examples/server/server.cpp
 +++ b/examples/server/server.cpp
-@@ -1857,12 +1857,6 @@ struct llama_server_context
+@@ -1564,12 +1564,6 @@ struct llama_server_context
                          LOG_TEE("slot %d : in cache: %i tokens | to process: %i tokens\n", slot.id, slot.n_past, slot.num_prompt_tokens_processed);
                      }
  
@@ -15,8 +15,8 @@ index 0462fbd2..4fa7b57f 100644
                      if (slot.n_past == slot.num_prompt_tokens && slot.n_past > 0)
                      {
                          // we have to evaluate at least 1 token to generate logits.
-@@ -1870,6 +1864,12 @@ struct llama_server_context
-                         slot.n_past--;
+@@ -1581,6 +1575,12 @@ struct llama_server_context
+                         }
                      }
  
 +                    LOG_TEE("slot %d : kv cache rm - [%d, end)\n", slot.id, (int) system_tokens.size() + slot.n_past);

llm/patches/02-shutdown.diff

@@ -0,0 +1,90 @@
+diff --git a/examples/server/server.cpp b/examples/server/server.cpp
+index 11dd82c3..311495a8 100644
+--- a/examples/server/server.cpp
++++ b/examples/server/server.cpp
+@@ -28,6 +28,7 @@
+ #include <chrono>
+ #include <condition_variable>
+ #include <atomic>
++#include <signal.h>
+ 
+ using json = nlohmann::json;
+ 
+@@ -2394,6 +2395,9 @@ static void append_to_generated_text_from_generated_token_probs(llama_server_con
+     }
+ }
+ 
++std::function<void(int)> shutdown_handler;
++inline void signal_handler(int signal) { shutdown_handler(signal); }
++
+ int main(int argc, char **argv)
+ {
+ #if SERVER_VERBOSE != 1
+@@ -3014,8 +3018,14 @@ int main(int argc, char **argv)
+         std::placeholders::_2,
+         std::placeholders::_3
+     ));
+-    llama.queue_tasks.start_loop();
+ 
++    shutdown_handler = [&](int) {
++        llama.queue_tasks.terminate();
++    };
++    signal(SIGTERM, signal_handler);
++    signal(SIGINT, signal_handler);
++    llama.queue_tasks.start_loop();
++    svr.stop();
+     t.join();
+ 
+     llama_backend_free();
+diff --git a/examples/server/utils.hpp b/examples/server/utils.hpp
+index 70cce072..2acb1eab 100644
+--- a/examples/server/utils.hpp
++++ b/examples/server/utils.hpp
+@@ -6,6 +6,7 @@
+ #include <mutex>
+ #include <condition_variable>
+ #include <unordered_map>
++#include <atomic>
+ 
+ #include "json.hpp"
+ 
+@@ -190,6 +191,7 @@ inline std::string format_chatml(std::vector<json> messages)
+ struct llama_server_queue {
+     int id = 0;
+     std::mutex mutex_tasks;
++    std::atomic<bool> running;
+     // queues
+     std::vector<task_server> queue_tasks;
+     std::vector<task_server> queue_tasks_deferred;
+@@ -248,9 +250,15 @@ struct llama_server_queue {
+         queue_tasks_deferred.clear();
+     }
+ 
+-    // Start the main loop. This call is blocking
+-    [[noreturn]]
++    // end the start_loop routine
++    void terminate() {
++        running = false;
++        condition_tasks.notify_all();
++    }
++
++    // Start the main loop.
+     void start_loop() {
++        running = true;
+         while (true) {
+             // new task arrived
+             LOG_VERBOSE("have new task", {});
+@@ -294,8 +302,12 @@ struct llama_server_queue {
+             {
+                 std::unique_lock<std::mutex> lock(mutex_tasks);
+                 if (queue_tasks.empty()) {
++                    if (!running.load()) {
++                        LOG_VERBOSE("ending start_loop", {});
++                        return;
++                    }
+                     condition_tasks.wait(lock, [&]{
+-                        return !queue_tasks.empty();
++                        return (!queue_tasks.empty() || !running.load());
+                     });
+                 }
+             }