Reuse ML load prepared statement (#16240)

Reuse ML load prepared statement and release resources on each batch load
Fix parameter to ML model load to be in seconds not usec

4 files changed, 21 insertions, 9 deletions

diff --git a/database/sqlite/sqlite_metadata.c b/database/sqlite/sqlite_metadata.c
index 54f9e3bedc..f0c102d97a 100644
--- a/database/sqlite/sqlite_metadata.c
+++ b/database/sqlite/sqlite_metadata.c
@@ -1539,13 +1539,20 @@ static void start_ml_model_load(uv_work_t *req __maybe_unused)
     RRDDIM *rd;
     RRDDIM_ACQUIRED *rda;
     internal_error(true, "Batch ML load loader, %zu items", ml_data->count);
+
+    sqlite3_stmt *ml_load_stmt = NULL;
     while((PValue = JudyLFirstThenNext(ml_data->JudyL, &Index, &first))) {
         UNUSED(PValue);
         rda = (RRDDIM_ACQUIRED *) Index;
         rd = rrddim_acquired_to_rrddim(rda);
-        ml_dimension_load_models(rd);
+        ml_dimension_load_models(rd, &ml_load_stmt);
         rrddim_acquired_release(rda);
     }
+
+    if (ml_load_stmt) {
+        sqlite3_finalize(ml_load_stmt);
+        ml_load_stmt = NULL;
+    }
     worker_is_idle();
 }
 
diff --git a/ml/ml-dummy.c b/ml/ml-dummy.c
index 2ad6cc7266..7058e21cdb 100644
--- a/ml/ml-dummy.c
+++ b/ml/ml-dummy.c
@@ -100,7 +100,7 @@ bool ml_dimension_is_anomalous(RRDDIM *rd, time_t curr_time, double value, bool
     return false;
 }
 
-int ml_dimension_load_models(RRDDIM *rd) {
+int ml_dimension_load_models(RRDDIM *rd, sqlite3_stmt **stmp) {
     UNUSED(rd);
     return 0;
 }
diff --git a/ml/ml.cc b/ml/ml.cc
index 0bba2060d7..5f8f5033e6 100644
--- a/ml/ml.cc
+++ b/ml/ml.cc
@@ -621,7 +621,7 @@ bind_fail:
     return rc;
 }
 
-int ml_dimension_load_models(RRDDIM *rd) {
+int ml_dimension_load_models(RRDDIM *rd, sqlite3_stmt **active_stmt) {
     ml_dimension_t *dim = (ml_dimension_t *) rd->ml_dimension;
     if (!dim)
         return 0;
@@ -635,7 +635,7 @@ int ml_dimension_load_models(RRDDIM *rd) {
 
     std::vector<ml_kmeans_t> V;
 
-    static __thread sqlite3_stmt *res = NULL;
+    sqlite3_stmt *res = active_stmt ? *active_stmt : NULL;
     int rc = 0;
     int param = 0;
 
@@ -645,18 +645,20 @@ int ml_dimension_load_models(RRDDIM *rd) {
     }
 
     if (unlikely(!res)) {
-        rc = prepare_statement(db, db_models_load, &res);
+        rc = sqlite3_prepare_v2(db, db_models_load, -1, &res, NULL);
         if (unlikely(rc != SQLITE_OK)) {
             error_report("Failed to prepare statement to load models, rc = %d", rc);
             return 1;
         }
+        if (active_stmt)
+            *active_stmt = res;
     }
 
     rc = sqlite3_bind_blob(res, ++param, &dim->rd->metric_uuid, sizeof(dim->rd->metric_uuid), SQLITE_STATIC);
     if (unlikely(rc != SQLITE_OK))
         goto bind_fail;
 
-    rc = sqlite3_bind_int(res, ++param, now_realtime_usec() - (Cfg.num_models_to_use * Cfg.max_train_samples));
+    rc = sqlite3_bind_int64(res, ++param, now_realtime_sec() - (Cfg.num_models_to_use * Cfg.max_train_samples));
     if (unlikely(rc != SQLITE_OK))
         goto bind_fail;
 
@@ -702,9 +704,12 @@ int ml_dimension_load_models(RRDDIM *rd) {
     if (unlikely(rc != SQLITE_DONE))
         error_report("Failed to load models, rc = %d", rc);
 
-    rc = sqlite3_reset(res);
+    if (active_stmt)
+        rc = sqlite3_reset(res);
+    else
+        rc = sqlite3_finalize(res);
     if (unlikely(rc != SQLITE_OK))
-        error_report("Failed to reset statement when loading models, rc = %d", rc);
+        error_report("Failed to %s statement when loading models, rc = %d", active_stmt ? "reset" : "finalize", rc);
 
     return 0;
 
diff --git a/ml/ml.h b/ml/ml.h
index 76e366fcf9..f6e7a54364 100644
--- a/ml/ml.h
+++ b/ml/ml.h
@@ -40,7 +40,7 @@ void ml_dimension_new(RRDDIM *rd);
 void ml_dimension_delete(RRDDIM *rd);
 bool ml_dimension_is_anomalous(RRDDIM *rd, time_t curr_time, double value, bool exists);
 
-int ml_dimension_load_models(RRDDIM *rd);
+int ml_dimension_load_models(RRDDIM *rd, sqlite3_stmt **stmt);
 
 void ml_update_global_statistics_charts(uint64_t models_consulted);