Merge branch 'master' into gg/refactor-k-shift

CMakeLists.txt

@@ -936,10 +936,16 @@ if (CMAKE_OSX_ARCHITECTURES STREQUAL "arm64" OR CMAKE_GENERATOR_PLATFORM_LWR STR
             list(APPEND ARCH_FLAGS -mfpu=neon-fp-armv8 -mno-unaligned-access)
         endif()
         if (${CMAKE_SYSTEM_PROCESSOR} MATCHES "armv7")
-            # Raspberry Pi 2
+            if ("${CMAKE_SYSTEM_NAME}" STREQUAL "Android")
-            list(APPEND ARCH_FLAGS -mfpu=neon-fp-armv8 -mno-unaligned-access -funsafe-math-optimizations)
+                # Android armeabi-v7a
+                list(APPEND ARCH_FLAGS -mfpu=neon-vfpv4 -mno-unaligned-access -funsafe-math-optimizations)
+            else()
+                # Raspberry Pi 2
+                list(APPEND ARCH_FLAGS -mfpu=neon-fp-armv8 -mno-unaligned-access -funsafe-math-optimizations)
+            endif()
         endif()
         if (${CMAKE_SYSTEM_PROCESSOR} MATCHES "armv8")
+            # Android arm64-v8a
             # Raspberry Pi 3, 4, Zero 2 (32-bit)
             list(APPEND ARCH_FLAGS -mno-unaligned-access)
         endif()

examples/server/README.md

@@ -39,9 +39,12 @@ see https://github.com/ggerganov/llama.cpp/issues/1437
 - `--mmproj MMPROJ_FILE`: Path to a multimodal projector file for LLaVA.
 - `--grp-attn-n`: Set the group attention factor to extend context size through self-extend(default: 1=disabled), used together with group attention width `--grp-attn-w`
 - `--grp-attn-w`: Set the group attention width to extend context size through self-extend(default: 512), used together with group attention factor `--grp-attn-n`
-- `-n, --n-predict`: Set the maximum tokens to predict (default: -1)
+- `-n N, --n-predict N`: Set the maximum tokens to predict (default: -1)
 - `--slots-endpoint-disable`: To disable slots state monitoring endpoint. Slots state may contain user data, prompts included.
+- `--metrics`: enable prometheus `/metrics` compatible endpoint (default: disabled)
 - `--chat-template JINJA_TEMPLATE`: Set custom jinja chat template. This parameter accepts a string, not a file name (default: template taken from model's metadata). We only support [some pre-defined templates](https://github.com/ggerganov/llama.cpp/wiki/Templates-supported-by-llama_chat_apply_template)
+- `--log-disable`: Output logs to stdout only, default: enabled.
+- `--log-format FORMAT`: Define the log output to FORMAT: json or text (default: json)
 
 ## Build
 
@@ -457,6 +460,18 @@ Notice that each `probs` is an array of length `n_probs`.
 ]
 ```
 
+- **GET** `/metrics`: [Prometheus](https://prometheus.io/) compatible metrics exporter endpoint if `--metrics` is enabled:
+
+Available metrics:
+- `llamacpp:prompt_tokens_total`: Number of prompt tokens processed.
+- `llamacpp:tokens_predicted_total`: Number of generation tokens processed.
+- `llamacpp:prompt_tokens_seconds`: Average prompt throughput in tokens/s.
+- `llamacpp:predicted_tokens_seconds`: Average generation throughput in tokens/s.
+- `llamacpp:kv_cache_usage_ratio`: KV-cache usage. 1 means 100 percent usage.
+- `llamacpp:kv_cache_tokens`: KV-cache tokens.
+- `llamacpp:requests_processing`: Number of request processing.
+- `llamacpp:requests_deferred`: Number of request deferred.
+
 ## More examples
 
 ### Change system prompt on runtime

examples/server/server.cpp

@@ -43,9 +43,11 @@ struct server_params
     int32_t read_timeout = 600;
     int32_t write_timeout = 600;
     bool slots_endpoint = true;
+    bool metrics_endpoint = false;
 };
 
 bool server_verbose = false;
+bool server_log_json = true;
 
 static size_t common_part(const std::vector<llama_token> &a, const std::vector<llama_token> &b)
 {
@@ -301,12 +303,76 @@ struct llama_client_slot
     }
 
     void print_timings() const {
-        LOG_TEE("\n");
+       char buffer[512];
-        LOG_TEE("%s: prompt eval time = %10.2f ms / %5d tokens (%8.2f ms per token, %8.2f tokens per second)\n",
+        double t_token = t_prompt_processing / num_prompt_tokens_processed;
-            __func__, t_prompt_processing, num_prompt_tokens_processed, t_prompt_processing / num_prompt_tokens_processed, 1e3 / t_prompt_processing * num_prompt_tokens_processed);
+        double n_tokens_second = 1e3 / t_prompt_processing * num_prompt_tokens_processed;
-        LOG_TEE("%s:        eval time = %10.2f ms / %5d runs   (%8.2f ms per token, %8.2f tokens per second)\n",
+        sprintf(buffer, "prompt eval time     = %10.2f ms / %5d tokens (%8.2f ms per token, %8.2f tokens per second)",
-            __func__, t_token_generation, n_decoded,t_token_generation / n_decoded, 1e3 / t_token_generation * n_decoded);
+                t_prompt_processing, num_prompt_tokens_processed,
-        LOG_TEE("%s:       total time = %10.2f ms\n", __func__, t_prompt_processing + t_token_generation);
+                t_token, n_tokens_second);
+        LOG_INFO(buffer, {
+            {"slot_id",                     id},
+            {"task_id",                     task_id},
+            {"t_prompt_processing",         t_prompt_processing},
+            {"num_prompt_tokens_processed", num_prompt_tokens_processed},
+            {"t_token",                     t_token},
+            {"n_tokens_second",             n_tokens_second},
+        });
+
+        t_token = t_token_generation / n_decoded;
+        n_tokens_second = 1e3 / t_token_generation * n_decoded;
+        sprintf(buffer, "generation eval time = %10.2f ms / %5d runs   (%8.2f ms per token, %8.2f tokens per second)",
+                t_token_generation, n_decoded,
+                t_token, n_tokens_second);
+        LOG_INFO(buffer, {
+            {"slot_id",            id},
+            {"task_id",            task_id},
+            {"t_token_generation", t_token_generation},
+            {"n_decoded",          n_decoded},
+            {"t_token",            t_token},
+            {"n_tokens_second",    n_tokens_second},
+        });
+
+        sprintf(buffer, "          total time = %10.2f ms", t_prompt_processing + t_token_generation);
+        LOG_INFO(buffer, {
+            {"slot_id",             id},
+            {"task_id",             task_id},
+            {"t_prompt_processing", t_prompt_processing},
+            {"t_token_generation",  t_token_generation},
+            {"t_total",             t_prompt_processing + t_token_generation},
+        });
+    }
+};
+
+struct llama_metrics {
+    uint64_t n_prompt_tokens_processed_total = 0;
+    uint64_t n_tokens_predicted_total        = 0;
+
+    uint64_t n_prompt_tokens_processed = 0;
+    uint64_t t_prompt_processing       = 0;
+
+    uint64_t n_tokens_predicted       = 0;
+    uint64_t t_tokens_generation      = 0;
+
+
+    void on_prompt_eval(const llama_client_slot &slot) {
+        n_prompt_tokens_processed_total += slot.num_prompt_tokens_processed;
+
+        n_prompt_tokens_processed += slot.num_prompt_tokens_processed;
+        t_prompt_processing       += slot.t_prompt_processing;
+    }
+
+    void on_prediction(const llama_client_slot &slot) {
+        n_tokens_predicted_total += slot.n_decoded;
+
+        n_tokens_predicted  += slot.n_decoded;
+        t_tokens_generation += slot.t_token_generation;
+    }
+
+    void reset_bucket() {
+        n_prompt_tokens_processed = 0;
+        t_prompt_processing       = 0;
+        n_tokens_predicted        = 0;
+        t_tokens_generation       = 0;
     }
 };
 
@@ -344,6 +410,8 @@ struct llama_server_context
     llama_server_queue queue_tasks;
     llama_server_response queue_results;
 
+    llama_metrics metrics;
+
     ~llama_server_context()
     {
         if (ctx)
@@ -363,7 +431,7 @@ struct llama_server_context
         params = params_;
         if (!params.mmproj.empty()) {
             multimodal = true;
-            LOG_TEE("Multi Modal Mode Enabled");
+            LOG_INFO("Multi Modal Mode Enabled", {});
             clp_ctx = clip_model_load(params.mmproj.c_str(), /*verbosity=*/ 1);
             if(clp_ctx == nullptr) {
                 LOG_ERROR("unable to load clip model", {{"model", params.mmproj}});
@@ -416,7 +484,7 @@ struct llama_server_context
 
         const int32_t n_ctx_slot = n_ctx / params.n_parallel;
 
-        LOG_TEE("Available slots:\n");
+        LOG_INFO("initializing slots", {{"n_slots", params.n_parallel}});
         for (int i = 0; i < params.n_parallel; i++)
         {
             llama_client_slot slot;
@@ -425,7 +493,10 @@ struct llama_server_context
             slot.n_ctx = n_ctx_slot;
             slot.n_predict = params.n_predict;
 
-            LOG_TEE(" -> Slot %i - max context: %i\n", slot.id, n_ctx_slot);
+            LOG_INFO("new slot", {
+                {"slot_id",    slot.id},
+                {"n_ctx_slot", slot.n_ctx}
+            });
 
             const int ga_n = params.grp_attn_n;
             const int ga_w = params.grp_attn_w;
@@ -435,7 +506,12 @@ struct llama_server_context
                 GGML_ASSERT(ga_w % ga_n == 0            && "ga_w must be a multiple of ga_n");     // NOLINT
                 //GGML_ASSERT(n_ctx_train % ga_w == 0     && "n_ctx_train must be a multiple of ga_w");    // NOLINT
                 //GGML_ASSERT(n_ctx >= n_ctx_train * ga_n && "n_ctx must be at least n_ctx_train * ga_n"); // NOLINT
-                LOG_TEE(" -> Slot %i - self-extend: ga_n = %d, ga_w = %d\n", slot.id, ga_n, ga_w);
+
+                LOG_INFO("slot self-extend", {
+                    {"slot_id",   slot.id},
+                    {"ga_n",      ga_n},
+                    {"ga_w",      ga_w}
+                });
             }
 
             slot.ga_i = 0;
@@ -729,10 +805,16 @@ struct llama_server_context
                     img_sl.img_data = clip_image_u8_init();
                     if (!clip_image_load_from_bytes(image_buffer.data(), image_buffer.size(), img_sl.img_data))
                     {
-                        LOG_TEE("slot %i - failed to load image [id: %i]\n", slot->id, img_sl.id);
+                        LOG_ERROR("failed to load image", {
+                            {"slot_id",   slot->id},
+                            {"img_sl_id", img_sl.id}
+                        });
                         return false;
                     }
-                    LOG_TEE("slot %i - loaded image\n", slot->id);
+                    LOG_VERBOSE("image loaded", {
+                        {"slot_id",   slot->id},
+                        {"img_sl_id", img_sl.id}
+                    });
                     img_sl.request_encode_image = true;
                     slot->images.push_back(img_sl);
                 }
@@ -792,7 +874,10 @@ struct llama_server_context
 
         all_slots_are_idle = false;
 
-        LOG_TEE("slot %i is processing [task id: %i]\n", slot->id, slot->task_id);
+        LOG_INFO("slot is processing task", {
+            {"slot_id", slot->id},
+            {"task_id", slot->task_id},
+        });
 
         return true;
     }
@@ -1355,7 +1440,7 @@ struct llama_server_context
                 if (slot == nullptr)
                 {
                     // if no slot is available, we defer this task for processing later
-                    LOG_VERBOSE("no slot is available", {});
+                    LOG_VERBOSE("no slot is available", {{"task_id", task.id}});
                     queue_tasks.defer(task);
                     break;
                 }
@@ -1404,7 +1489,7 @@ struct llama_server_context
             case TASK_TYPE_NEXT_RESPONSE: {
                 // do nothing
             } break;
-            case TASK_TYPE_SLOTS_DATA: {
+            case TASK_TYPE_METRICS: {
                 json slots_data        = json::array();
                 int n_idle_slots       = 0;
                 int n_processing_slots = 0;
@@ -1431,17 +1516,41 @@ struct llama_server_context
                     }
                     slots_data.push_back(slot_data);
                 }
-                LOG_TEE("task %i - slots data: idle=%i processing=%i\n", task.id, n_idle_slots, n_processing_slots);
+                LOG_INFO("slot data", {
+                    {"task_id",            task.id},
+                    {"n_idle_slots",       n_idle_slots},
+                    {"n_processing_slots", n_processing_slots}
+                });
+                LOG_VERBOSE("slot data", {
+                    {"task_id",            task.id},
+                    {"n_idle_slots",       n_idle_slots},
+                    {"n_processing_slots", n_processing_slots},
+                    {"slots",              slots_data}
+                });
                 task_result res;
                 res.id = task.id;
                 res.multitask_id = task.multitask_id;
                 res.stop = true;
                 res.error = false;
                 res.result_json = {
-                        { "idle",       n_idle_slots       },
+                        { "idle",                            n_idle_slots       },
-                        { "processing", n_processing_slots },
+                        { "processing",                      n_processing_slots },
-                        { "slots",      slots_data         }
+                        { "deferred",                        queue_tasks.queue_tasks_deferred.size() },
+
+                        { "n_prompt_tokens_processed_total", metrics.n_prompt_tokens_processed_total},
+                        { "n_tokens_predicted_total",        metrics.n_tokens_predicted_total},
+
+                        { "n_prompt_tokens_processed",       metrics.n_prompt_tokens_processed},
+                        { "t_prompt_processing",             metrics.t_prompt_processing},
+                        { "n_tokens_predicted",              metrics.n_tokens_predicted},
+                        { "t_tokens_generation",             metrics.t_tokens_generation},
+
+                        { "kv_cache_tokens_count",          llama_get_kv_cache_token_count(ctx)},
+                        { "kv_cache_used_cells",            llama_get_kv_cache_used_cells(ctx)},
+
+                        { "slots",                          slots_data },
                 };
+                metrics.reset_bucket();
                 queue_results.send(res);
             } break;
         }
@@ -1469,7 +1578,7 @@ struct llama_server_context
     bool update_slots() {
         if (system_need_update)
         {
-            LOG_TEE("updating system prompt\n");
+            LOG_INFO("updating system prompt", {});
             update_system_prompt();
         }
 
@@ -1479,12 +1588,13 @@ struct llama_server_context
         {
             if (system_prompt.empty() && clean_kv_cache)
             {
-                LOG_TEE("all slots are idle and system prompt is empty, clear the KV cache\n");
+                LOG_INFO("all slots are idle and system prompt is empty, clear the KV cache", {});
                 kv_cache_clear();
             }
             return true;
         }
 
+        LOG_VERBOSE("posting NEXT_RESPONSE", {});
         task_server task;
         task.type = TASK_TYPE_NEXT_RESPONSE;
         task.target_id = -1;
@@ -1498,10 +1608,20 @@ struct llama_server_context
                 {
                     // Shift context
                     const int n_keep    = slot.params.n_keep + add_bos_token;
-                    const int n_left    = system_tokens.size() + slot.n_past - n_keep;
+                    const int n_left    = (int) system_tokens.size() + slot.n_past - n_keep;
                     const int n_discard = n_left / 2;
 
-                    LOG_TEE("slot %d: context shift - n_keep = %d, n_left = %d, n_discard = %d\n", slot.id, n_keep, n_left, n_discard);
+                    LOG_INFO("slot context shift", {
+                        {"slot_id",         slot.id},
+                        {"task_id",         slot.task_id},
+                        {"n_keep",          n_keep},
+                        {"n_left",          n_left},
+                        {"n_discard",       n_discard},
+                        {"n_ctx",           n_ctx},
+                        {"n_past",          slot.n_past},
+                        {"n_system_tokens", system_tokens.size()},
+                        {"n_cache_tokens",  slot.cache_tokens.size()}
+                    });
                     llama_kv_cache_seq_rm (ctx, slot.id, n_keep            , n_keep + n_discard);
                     llama_kv_cache_seq_add(ctx, slot.id, n_keep + n_discard, system_tokens.size() + slot.n_past, -n_discard);
 
@@ -1515,17 +1635,12 @@ struct llama_server_context
                     slot.n_past -= n_discard;
 
                     slot.truncated = true;
-
-                    LOG_VERBOSE("context shift", {
-                        { "n_ctx", n_ctx },
-                        { "n_keep", n_keep },
-                        { "n_left", n_left },
-                    });
                 }
             }
         }
 
         // decode any currently ongoing sequences
+        LOG_VERBOSE("decoding ongoing sequences", {});
         for (auto & slot : slots)
         {
             // release the slot
@@ -1535,7 +1650,15 @@ struct llama_server_context
                 slot.command = NONE;
                 slot.t_last_used = ggml_time_us();
 
-                LOG_TEE("slot %d released (%d tokens in cache)\n", slot.id, (int) slot.cache_tokens.size());
+                LOG_INFO("slot released", {
+                    {"slot_id",         slot.id},
+                    {"task_id",         slot.task_id},
+                    {"n_ctx",           n_ctx},
+                    {"n_past",          slot.n_past},
+                    {"n_system_tokens", system_tokens.size()},
+                    {"n_cache_tokens",  slot.cache_tokens.size()},
+                    {"truncated",       slot.truncated}
+                });
                 queue_tasks.notify_slot_changed();
 
                 continue;
@@ -1683,7 +1806,12 @@ struct llama_server_context
                             slot.ga_i = ga_i;
                         }
 
-                        LOG_TEE("slot %d : in cache: %i tokens | to process: %i tokens\n", slot.id, slot.n_past, slot.num_prompt_tokens_processed);
+                        LOG_INFO("slot progression", {
+                            { "slot_id", slot.id },
+                            { "task_id", slot.task_id },
+                            { "n_past",  slot.n_past },
+                            { "num_prompt_tokens_processed", slot.num_prompt_tokens_processed }
+                        });
                     }
 
                     slot.cache_tokens = prompt_tokens;
@@ -1691,7 +1819,10 @@ struct llama_server_context
                     if (slot.n_past == slot.num_prompt_tokens && slot.n_past > 0)
                     {
                         // we have to evaluate at least 1 token to generate logits.
-                        LOG_TEE("slot %d : we have to evaluate at least 1 token to generate logits\n", slot.id);
+                        LOG_INFO("we have to evaluate at least 1 token to generate logits", {
+                            { "slot_id", slot.id },
+                            { "task_id", slot.task_id }
+                        });
                         slot.n_past--;
                         if (slot.ga_i > 0)
                         {
@@ -1699,9 +1830,13 @@ struct llama_server_context
                         }
                     }
 
-                    LOG_TEE("slot %d : kv cache rm - [%d, end)\n", slot.id, (int) system_tokens.size() + slot.n_past);
+                    int p0 = (int) system_tokens.size() + slot.n_past;
-
+                    LOG_INFO("kv cache rm [p0, end)", {
-                    llama_kv_cache_seq_rm(ctx, slot.id, system_tokens.size() + slot.n_past, -1);
+                        { "slot_id", slot.id },
+                        { "task_id", slot.task_id },
+                        { "p0",      p0 }
+                    });
+                    llama_kv_cache_seq_rm(ctx, slot.id, p0, -1);
 
                     LOG_VERBOSE("prompt ingested", {
                                                     {"n_past",  slot.n_past},
@@ -1736,7 +1871,13 @@ struct llama_server_context
 
                     if (has_images && !ingest_images(slot, n_batch))
                     {
-                        LOG_TEE("failed processing images\n");
+                        LOG_ERROR("failed processing images", {
+                            "slot_id", slot.id,
+                            "task_id", slot.task_id,
+                        });
+                        // FIXME @phymbert: to be properly tested
+                        //  early returning without changing the slot state will block the slot for ever
+                        // no one at the moment is checking the return value
                         return false;
                     }
 
@@ -1849,6 +1990,7 @@ struct llama_server_context
                 {
                     slot.t_start_genereration = ggml_time_us();
                     slot.t_prompt_processing = (slot.t_start_genereration - slot.t_start_process_prompt) / 1e3;
+                    metrics.on_prompt_eval(slot);
                 }
 
                 llama_token_data_array cur_p = { slot.ctx_sampling->cur.data(), slot.ctx_sampling->cur.size(), false };
@@ -1871,11 +2013,14 @@ struct llama_server_context
                     slot.release();
                     slot.print_timings();
                     send_final_response(slot);
+                    metrics.on_prediction(slot);
                 }
 
                 slot.i_batch = -1;
             }
         }
+
+        LOG_VERBOSE("slots updated", {});
         return true;
     }
 
@@ -1953,8 +2098,10 @@ static void server_print_usage(const char *argv0, const gpt_params &params,
     printf("  -ctv TYPE, --cache-type-v TYPE\n");
     printf("                            KV cache data type for V (default: f16)\n");
     printf("  --mmproj MMPROJ_FILE      path to a multimodal projector file for LLaVA.\n");
+    printf("  --log-format              log output format: json or text (default: json)\n");
     printf("  --log-disable             disables logging to a file.\n");
     printf("  --slots-endpoint-disable  disables slots monitoring endpoint.\n");
+    printf("  --metrics                 enable prometheus compatible metrics endpoint (default: %s).\n", sparams.metrics_endpoint ? "enabled" : "disabled");
     printf("\n");
     printf("  -n, --n-predict           maximum tokens to predict (default: %d)\n", params.n_predict);
     printf("  --override-kv KEY=TYPE:VALUE\n");
@@ -2405,6 +2552,27 @@ static void server_params_parse(int argc, char **argv, server_params &sparams,
             }
             params.mmproj = argv[i];
         }
+        else if (arg == "--log-format")
+        {
+            if (++i >= argc)
+            {
+                invalid_param = true;
+                break;
+            }
+            if (std::strcmp(argv[i], "json") == 0)
+            {
+                server_log_json = true;
+            }
+            else if (std::strcmp(argv[i], "text") == 0)
+            {
+                server_log_json = false;
+            }
+            else
+            {
+                invalid_param = true;
+                break;
+            }
+        }
         else if (arg == "--log-disable")
         {
             log_set_target(stdout);
@@ -2414,6 +2582,10 @@ static void server_params_parse(int argc, char **argv, server_params &sparams,
         {
             sparams.slots_endpoint = false;
         }
+        else if (arg == "--metrics")
+        {
+            sparams.metrics_endpoint = true;
+        }
         else if (arg == "--chat-template")
         {
             if (++i >= argc)
@@ -2514,32 +2686,40 @@ static json format_partial_response(
 
 static json format_tokenizer_response(const std::vector<llama_token> &tokens)
 {
-    return json{
+    return json {
-        {"tokens", tokens}};
+        {"tokens", tokens}
+    };
 }
 
 static json format_detokenized_response(std::string content)
 {
-    return json{
+    return json {
-        {"content", content}};
+        {"content", content}
+    };
 }
 
 
 static void log_server_request(const httplib::Request &req, const httplib::Response &res)
 {
+    // skip GH copilot requests when using default port
+    if (req.path == "/v1/health" || req.path == "/v1/completions")
+    {
+        return;
+    }
+
     LOG_INFO("request", {
-                            {"remote_addr", req.remote_addr},
+        {"remote_addr", req.remote_addr},
-                            {"remote_port", req.remote_port},
+        {"remote_port", req.remote_port},
-                            {"status", res.status},
+        {"status",      res.status},
-                            {"method", req.method},
+        {"method",      req.method},
-                            {"path", req.path},
+        {"path",        req.path},
-                            {"params", req.params},
+        {"params",      req.params},
-                        });
+    });
 
     LOG_VERBOSE("request", {
-                               {"request", req.body},
+        {"request",  req.body},
-                               {"response", res.body},
+        {"response", res.body},
-                           });
+    });
 }
 
 struct token_translator
@@ -2621,7 +2801,7 @@ int main(int argc, char **argv)
                 // request slots data using task queue
                 task_server task;
                 task.id   = llama.queue_tasks.get_new_id();
-                task.type = TASK_TYPE_SLOTS_DATA;
+                task.type = TASK_TYPE_METRICS;
                 task.target_id = -1;
 
                 llama.queue_results.add_waiting_task_id(task.id);
@@ -2668,7 +2848,7 @@ int main(int argc, char **argv)
             // request slots data using task queue
             task_server task;
             task.id = llama.queue_tasks.get_new_id();
-            task.type = TASK_TYPE_SLOTS_DATA;
+            task.type = TASK_TYPE_METRICS;
             task.target_id = -1;
 
             llama.queue_results.add_waiting_task_id(task.id);
@@ -2683,6 +2863,87 @@ int main(int argc, char **argv)
         });
     }
 
+    if (sparams.metrics_endpoint) {
+        svr.Get("/metrics", [&](const httplib::Request&, httplib::Response& res) {
+            // request slots data using task queue
+            task_server task;
+            task.id = llama.queue_tasks.get_new_id();
+            task.type = TASK_TYPE_METRICS;
+            task.target_id = -1;
+
+            llama.queue_results.add_waiting_task_id(task.id);
+            llama.queue_tasks.post(task);
+
+            // get the result
+            task_result result = llama.queue_results.recv(task.id);
+            llama.queue_results.remove_waiting_task_id(task.id);
+
+            json data = result.result_json;
+
+            uint64_t n_prompt_tokens_processed = data["n_prompt_tokens_processed"];
+            uint64_t t_prompt_processing       = data["t_prompt_processing"];
+
+            uint64_t n_tokens_predicted       = data["n_tokens_predicted"];
+            uint64_t t_tokens_generation      = data["t_tokens_generation"];
+
+            int32_t kv_cache_used_cells = data["kv_cache_used_cells"];
+
+            // metrics definition: https://prometheus.io/docs/practices/naming/#metric-names
+            json all_metrics_def = json {
+                    {"counter", {{
+                            {"name",  "prompt_tokens_total"},
+                            {"help",  "Number of prompt tokens processed."},
+                            {"value",  data["n_prompt_tokens_processed_total"]}
+                    }, {
+                            {"name",  "tokens_predicted_total"},
+                            {"help",  "Number of generation tokens processed."},
+                            {"value",  data["n_tokens_predicted_total"]}
+                    }}},
+                    {"gauge", {{
+                            {"name",  "prompt_tokens_seconds"},
+                            {"help",  "Average prompt throughput in tokens/s."},
+                            {"value",  n_prompt_tokens_processed ? 1e3 / t_prompt_processing * n_prompt_tokens_processed : 0}
+                    },{
+                            {"name",  "predicted_tokens_seconds"},
+                            {"help",  "Average generation throughput in tokens/s."},
+                            {"value",  n_tokens_predicted ? 1e3 / t_tokens_generation * n_tokens_predicted : 0}
+                     },{
+                            {"name",  "kv_cache_usage_ratio"},
+                            {"help",  "KV-cache usage. 1 means 100 percent usage."},
+                            {"value",  1. * kv_cache_used_cells / params.n_ctx}
+                     },{
+                            {"name",  "kv_cache_tokens"},
+                            {"help",  "KV-cache tokens."},
+                            {"value",  data["kv_cache_tokens_count"]}
+                    },{
+                            {"name",  "requests_processing"},
+                            {"help",  "Number of request processing."},
+                            {"value",  data["processing"]}
+                  },{
+                            {"name",  "requests_deferred"},
+                            {"help",  "Number of request deferred."},
+                            {"value",  data["deferred"]}
+                  }}}
+            };
+
+            std::stringstream prometheus;
+            for (const auto& el : all_metrics_def.items()) {
+                const auto& type = el.key();
+                const auto& metrics_def = el.value();
+                for (const auto& metric_def : metrics_def) {
+                    std::string name = metric_def["name"];
+                    std::string help = metric_def["help"];
+                    prometheus << "# HELP llamacpp:" << name << " " << help                << "\n"
+                               << "# TYPE llamacpp:" << name << " " << type                << "\n"
+                               << "llamacpp:"        << name << " " << metric_def["value"] << "\n";
+                }
+            }
+
+            res.set_content(prometheus.str(), "text/plain; version=0.0.4");
+            res.status = 200; // HTTP OK
+        });
+    }
+
     svr.set_logger(log_server_request);
 
     svr.set_exception_handler([](const httplib::Request &, httplib::Response &res, std::exception_ptr ep)
@@ -2735,9 +2996,6 @@ int main(int argc, char **argv)
     // Set the base directory for serving static files
     svr.set_base_dir(sparams.public_path);
 
-    // to make it ctrl+clickable:
-    LOG_TEE("\nllama server listening at http://%s:%d\n\n", sparams.hostname.c_str(), sparams.port);
-
     std::unordered_map<std::string, std::string> log_data;
     log_data["hostname"] = sparams.hostname;
     log_data["port"] = std::to_string(sparams.port);

examples/server/tests/README.md

@@ -32,6 +32,7 @@ It's possible to override some scenario steps values with environment variables:
  - `PORT` -> `context.server_port` to set the listening port of the server during scenario, default: `8080`
  - `LLAMA_SERVER_BIN_PATH` -> to change the server binary path, default: `../../../build/bin/server`
  - `DEBUG` -> "ON" to enable steps and server verbose mode `--verbose`
+ - `SERVER_LOG_FORMAT_JSON` -> if set switch server logs to json format
 
 ### Run @bug, @wip or @wrong_usage annotated scenario
 

examples/server/tests/features/environment.py

@@ -16,6 +16,8 @@ def before_scenario(context, scenario):
 
 
 def after_scenario(context, scenario):
+    if context.server_process is None:
+        return
     if scenario.status == "failed":
         if 'GITHUB_ACTIONS' in os.environ:
             print(f"\x1b[33;101mSCENARIO FAILED: {scenario.name} server logs:\x1b[0m\n\n")

examples/server/tests/features/server.feature

@@ -13,6 +13,7 @@ Feature: llama.cpp server
     And   1 slots
     And   embeddings extraction
     And   32 server max tokens to predict
+    And   prometheus compatible metrics exposed
     Then  the server is starting
     Then  the server is healthy
 
@@ -25,11 +26,12 @@ Feature: llama.cpp server
     And   <n_predict> max tokens to predict
     And   a completion request with no api error
     Then  <n_predicted> tokens are predicted matching <re_content>
+    And   prometheus metrics are exposed
 
     Examples: Prompts
-      | prompt                           | n_predict | re_content                   | n_predicted |
+      | prompt                           | n_predict | re_content                             | n_predicted |
-      | I believe the meaning of life is | 8         | read                         | 8           |
+      | I believe the meaning of life is | 8         | (read<or>going)+                       | 8           |
-      | Write a joke about AI            | 64        | (park<or>friends<or>scared)+ | 32          |
+      | Write a joke about AI            | 64        | (park<or>friends<or>scared<or>always)+ | 32          |
 
   Scenario Outline: OAI Compatibility
     Given a model <model>

examples/server/tests/features/steps/steps.py

@@ -13,6 +13,7 @@ import aiohttp
 import openai
 from behave import step
 from behave.api.async_step import async_run_until_complete
+from prometheus_client import parser
 
 
 @step(u"a server listening on {server_fqdn}:{server_port}")
@@ -34,6 +35,8 @@ def step_server_config(context, server_fqdn, server_port):
     context.server_api_key = None
     context.server_continuous_batching = False
     context.server_embeddings = False
+    context.server_metrics = False
+    context.server_process = None
     context.server_seed = None
     context.user_api_key = None
 
@@ -82,6 +85,11 @@ def step_server_embeddings(context):
     context.server_embeddings = True
 
 
+@step(u'prometheus compatible metrics exposed')
+def step_server_metrics(context):
+    context.server_metrics = True
+
+
 @step(u"the server is starting")
 def step_start_server(context):
     start_server_background(context)
@@ -424,6 +432,23 @@ def step_check_options_header_value(context, cors_header, cors_header_value):
     assert context.options_response.headers[cors_header] == cors_header_value
 
 
+@step(u'prometheus metrics are exposed')
+@async_run_until_complete
+async def step_prometheus_metrics_exported(context):
+    async with aiohttp.ClientSession() as session:
+        async with await session.get(f'{context.base_url}/metrics') as metrics_response:
+            assert metrics_response.status == 200
+            assert metrics_response.headers['Content-Type'] == "text/plain; version=0.0.4"
+            metrics_raw = await metrics_response.text()
+            metric_exported = False
+            for metric in parser.text_string_to_metric_families(metrics_raw):
+                match metric.name:
+                    case "llamacpp:kv_cache_usage_ratio":
+                        assert len(metric.samples) > 0
+                        metric_exported = True
+            assert metric_exported, "No metrics exported"
+
+
 async def concurrent_requests(context, f_completion, *args, **kwargs):
     n_prompts = len(context.prompts)
     if context.debug:
@@ -753,6 +778,8 @@ def start_server_background(context):
         server_args.append('--cont-batching')
     if context.server_embeddings:
         server_args.append('--embedding')
+    if context.server_metrics:
+        server_args.append('--metrics')
     if context.model_alias is not None:
         server_args.extend(['--alias', context.model_alias])
     if context.n_ctx is not None:
@@ -765,6 +792,8 @@ def start_server_background(context):
         server_args.extend(['--api-key', context.server_api_key])
     if context.debug:
         server_args.append('--verbose')
+    if 'SERVER_LOG_FORMAT_JSON' not in os.environ:
+        server_args.extend(['--log-format', "text"])
     print(f"starting server with: {context.server_path}", *server_args)
     context.server_process = subprocess.Popen(
         [str(arg) for arg in [context.server_path, *server_args]],

examples/server/tests/requirements.txt

@@ -1,3 +1,4 @@
 aiohttp~=3.9.3
 behave~=1.2.6
 openai~=0.25.0
+prometheus-client~=0.20.0

examples/server/utils.hpp

@@ -14,6 +14,7 @@
 using json = nlohmann::json;
 
 extern bool server_verbose;
+extern bool server_log_json;
 
 #ifndef SERVER_VERBOSE
 #define SERVER_VERBOSE 1
@@ -27,14 +28,14 @@ extern bool server_verbose;
     {                                                                    \
         if (server_verbose)                                              \
         {                                                                \
-            server_log("VERBOSE", __func__, __LINE__, MSG, __VA_ARGS__); \
+            server_log("VERB", __func__, __LINE__, MSG, __VA_ARGS__); \
         }                                                                \
     } while (0)
 #endif
 
-#define LOG_ERROR(  MSG, ...) server_log("ERROR",   __func__, __LINE__, MSG, __VA_ARGS__)
+#define LOG_ERROR(  MSG, ...) server_log("ERR",  __func__, __LINE__, MSG, __VA_ARGS__)
-#define LOG_WARNING(MSG, ...) server_log("WARNING", __func__, __LINE__, MSG, __VA_ARGS__)
+#define LOG_WARNING(MSG, ...) server_log("WARN", __func__, __LINE__, MSG, __VA_ARGS__)
-#define LOG_INFO(   MSG, ...) server_log("INFO",    __func__, __LINE__, MSG, __VA_ARGS__)
+#define LOG_INFO(   MSG, ...) server_log("INFO", __func__, __LINE__, MSG, __VA_ARGS__)
 
 //
 // parallel
@@ -50,7 +51,7 @@ enum task_type {
     TASK_TYPE_COMPLETION,
     TASK_TYPE_CANCEL,
     TASK_TYPE_NEXT_RESPONSE,
-    TASK_TYPE_SLOTS_DATA
+    TASK_TYPE_METRICS
 };
 
 struct task_server {
@@ -133,26 +134,48 @@ struct completion_token_output
     std::string text_to_send;
 };
 
-static inline void server_log(const char *level, const char *function, int line,
+static inline void server_log(const char *level, const char *function, int line, const char *message, const nlohmann::ordered_json &extra)
-                       const char *message, const nlohmann::ordered_json &extra)
 {
-    nlohmann::ordered_json log
+    std::stringstream ss_tid;
-    {
+    ss_tid << std::this_thread::get_id();
+    json log = nlohmann::ordered_json{
+        {"tid", ss_tid.str()},
         {"timestamp", time(nullptr)},
-        {"level",     level},
-        {"function",  function},
-        {"line",      line},
-        {"message",   message},
     };
 
-    if (!extra.empty())
+    if (server_log_json) {
-    {
+        log.merge_patch(
-        log.merge_patch(extra);
+                {
-    }
+                        {"level",     level},
+                        {"function",  function},
+                        {"line",      line},
+                        {"msg",       message},
+                });
+        if (!extra.empty()) {
+            log.merge_patch(extra);
+        }
 
-    const std::string str = log.dump(-1, ' ', false, json::error_handler_t::replace);
+        std::cout << log.dump(-1, ' ', false, json::error_handler_t::replace) << "\n" << std::flush;
-    printf("%.*s\n", (int)str.size(), str.data());
+    } else {
-    fflush(stdout);
+        char buf[1024];
+        snprintf(buf, 1024, "%4s [%24s] %s", level, function, message);
+
+        if (!extra.empty()) {
+            log.merge_patch(extra);
+        }
+        std::stringstream ss;
+        ss << buf << " |";
+        for (const auto& el : log.items())
+        {
+            const std::string value = el.value().dump(-1, ' ', false, json::error_handler_t::replace);
+            snprintf(buf, 1024, " %s=%s", el.key().c_str(), value.c_str());
+            ss << buf;
+        }
+
+        const std::string str = ss.str();
+        printf("%.*s\n", (int)str.size(), str.data());
+        fflush(stdout);
+    }
 }
 
 //
@@ -234,6 +257,7 @@ struct llama_server_queue {
         std::unique_lock<std::mutex> lock(mutex_tasks);
         if (task.id == -1) {
             task.id = id++;
+            LOG_VERBOSE("new task id", {{"new_id", task.id}});
         }
         queue_tasks.push_back(std::move(task));
         condition_tasks.notify_one();
@@ -249,7 +273,9 @@ struct llama_server_queue {
     // Get the next id for creating anew task
     int get_new_id() {
         std::unique_lock<std::mutex> lock(mutex_tasks);
-        return id++;
+        int new_id = id++;
+        LOG_VERBOSE("new task id", {{"new_id", new_id}});
+        return new_id;
     }
 
     // Register function to process a new task
@@ -290,8 +316,7 @@ struct llama_server_queue {
     void start_loop() {
         running = true;
         while (true) {
-            // new task arrived
+            LOG_VERBOSE("new task may arrive", {});
-            LOG_VERBOSE("have new task", {});
             {
                 while (true)
                 {
@@ -303,7 +328,7 @@ struct llama_server_queue {
                     task_server task = queue_tasks.front();
                     queue_tasks.erase(queue_tasks.begin());
                     lock.unlock();
-                    LOG_VERBOSE("callback_new_task", {});
+                    LOG_VERBOSE("callback_new_task", {{"task_id", task.id}});
                     callback_new_task(task);
                 }
                 LOG_VERBOSE("callback_all_task_finished", {});
@@ -384,11 +409,13 @@ struct llama_server_response {
     std::condition_variable condition_results;
 
     void add_waiting_task_id(int task_id) {
+        LOG_VERBOSE("waiting for task id", {{"task_id", task_id}});
         std::unique_lock<std::mutex> lock(mutex_results);
         waiting_task_ids.insert(task_id);
     }
 
     void remove_waiting_task_id(int task_id) {
+        LOG_VERBOSE("remove waiting for task id", {{"task_id", task_id}});
         std::unique_lock<std::mutex> lock(mutex_results);
         waiting_task_ids.erase(task_id);
     }
@@ -401,7 +428,6 @@ struct llama_server_response {
             condition_results.wait(lock, [&]{
                 return !queue_results.empty();
             });
-            LOG_VERBOSE("condition_results unblock", {});
 
             for (int i = 0; i < (int) queue_results.size(); i++)
             {
@@ -426,22 +452,22 @@ struct llama_server_response {
     // Send a new result to a waiting task_id
     void send(task_result result) {
         std::unique_lock<std::mutex> lock(mutex_results);
-        LOG_VERBOSE("send new result", {});
+        LOG_VERBOSE("send new result", {{"task_id", result.id}});
         for (auto& task_id : waiting_task_ids) {
             // LOG_TEE("waiting task id %i \n", task_id);
             // for now, tasks that have associated parent multitasks just get erased once multitask picks up the result
             if (result.multitask_id == task_id)
             {
-                LOG_VERBOSE("callback_update_multitask", {});
+                LOG_VERBOSE("callback_update_multitask", {{"task_id", task_id}});
                 callback_update_multitask(task_id, result.id, result);
                 continue;
             }
 
             if (result.id == task_id)
             {
-                LOG_VERBOSE("queue_results.push_back", {});
+                LOG_VERBOSE("queue_results.push_back", {{"task_id", task_id}});
                 queue_results.push_back(result);
-                condition_results.notify_one();
+                condition_results.notify_all();
                 return;
             }
         }