Skip ML initialization when it's been disabled in netdata.conf (#14920)

* Apply ML changes again.

The ML changes in 003df5f2 wheere reverted with
556bdad9 because we were partially initializing
ML even when it was explicitly disabled in
netdata.conf, causing the agent to crash on
startup.

* Do not start/stop ML threads when ML is disabled.

* Restore default config settings.

3 files changed, 19 insertions, 47 deletions

diff --git a/daemon/global_statistics.c b/daemon/global_statistics.c
index 0dc3ee6452..ee68bebd15 100644
--- a/daemon/global_statistics.c
+++ b/daemon/global_statistics.c
@@ -827,33 +827,7 @@ static void global_statistics_charts(void) {
         rrdset_done(st_points_stored);
     }
 
-    {
-        static RRDSET *st = NULL;
-        static RRDDIM *rd = NULL;
-
-        if (unlikely(!st)) {
-            st = rrdset_create_localhost(
-                    "netdata" // type
-                    , "ml_models_consulted" // id
-                    , NULL // name
-                    , NETDATA_ML_CHART_FAMILY // family
-                    , NULL // context
-                    , "KMeans models used for prediction" // title
-                    , "models" // units
-                    , NETDATA_ML_PLUGIN // plugin
-                    , NETDATA_ML_MODULE_DETECTION // module
-                    , NETDATA_ML_CHART_PRIO_MACHINE_LEARNING_STATUS // priority
-                    , localhost->rrd_update_every // update_every
-                    , RRDSET_TYPE_AREA // chart_type
-            );
-
-            rd = rrddim_add(st, "num_models_consulted", NULL, 1, 1, RRD_ALGORITHM_INCREMENTAL);
-        }
-
-        rrddim_set_by_pointer(st, rd, (collected_number) gs.ml_models_consulted);
-
-        rrdset_done(st);
-    }
+    ml_update_global_statistics_charts(gs.ml_models_consulted);
 }
 
 // ----------------------------------------------------------------------------
diff --git a/daemon/main.c b/daemon/main.c
index 682106b78e..478b5d002c 100644
--- a/daemon/main.c
+++ b/daemon/main.c
@@ -148,10 +148,6 @@ static void service_to_buffer(BUFFER *wb, SERVICE_TYPE service) {
         buffer_strcat(wb, "MAINTENANCE ");
     if(service & SERVICE_COLLECTORS)
         buffer_strcat(wb, "COLLECTORS ");
-    if(service & SERVICE_ML_TRAINING)
-        buffer_strcat(wb, "ML_TRAINING ");
-    if(service & SERVICE_ML_PREDICTION)
-        buffer_strcat(wb, "ML_PREDICTION ");
     if(service & SERVICE_REPLICATION)
         buffer_strcat(wb, "REPLICATION ");
     if(service & ABILITY_DATA_QUERIES)
@@ -340,6 +336,11 @@ void netdata_cleanup_and_exit(int ret) {
     }
 #endif
 
+    delta_shutdown_time("disable ML detection and training threads");
+
+    ml_stop_threads();
+    ml_fini();
+
     delta_shutdown_time("disable maintenance, new queries, new web requests, new streaming connections and aclk");
 
     service_signal_exit(
@@ -351,12 +352,11 @@ void netdata_cleanup_and_exit(int ret) {
             | SERVICE_ACLKSYNC
             );
 
-    delta_shutdown_time("stop replication, exporters, ML training, health and web servers threads");
+    delta_shutdown_time("stop replication, exporters, health and web servers threads");
 
     timeout = !service_wait_exit(
             SERVICE_REPLICATION
             | SERVICE_EXPORTERS
-            | SERVICE_ML_TRAINING
             | SERVICE_HEALTH
             | SERVICE_WEB_SERVER
             , 3 * USEC_PER_SEC);
@@ -368,11 +368,10 @@ void netdata_cleanup_and_exit(int ret) {
             | SERVICE_STREAMING
             , 3 * USEC_PER_SEC);
 
-    delta_shutdown_time("stop ML prediction and context threads");
+    delta_shutdown_time("stop context thread");
 
     timeout = !service_wait_exit(
-            SERVICE_ML_PREDICTION
-            | SERVICE_CONTEXT
+            SERVICE_CONTEXT
             , 3 * USEC_PER_SEC);
 
     delta_shutdown_time("stop maintenance thread");
@@ -2085,6 +2084,7 @@ int main(int argc, char **argv) {
         }
         else debug(D_SYSTEM, "Not starting thread %s.", st->name);
     }
+    ml_start_threads();
 
     // ------------------------------------------------------------------------
     // Initialize netdata agent command serving from cli and signals
diff --git a/daemon/main.h b/daemon/main.h
index 7e659e939a..3e32c5ad6d 100644
--- a/daemon/main.h
+++ b/daemon/main.h
@@ -33,17 +33,15 @@ typedef enum {
     ABILITY_STREAMING_CONNECTIONS = (1 << 2),
     SERVICE_MAINTENANCE           = (1 << 3),
     SERVICE_COLLECTORS            = (1 << 4),
-    SERVICE_ML_TRAINING           = (1 << 5),
-    SERVICE_ML_PREDICTION         = (1 << 6),
-    SERVICE_REPLICATION           = (1 << 7),
-    SERVICE_WEB_SERVER            = (1 << 8),
-    SERVICE_ACLK                  = (1 << 9),
-    SERVICE_HEALTH                = (1 << 10),
-    SERVICE_STREAMING             = (1 << 11),
-    SERVICE_CONTEXT               = (1 << 12),
-    SERVICE_ANALYTICS             = (1 << 13),
-    SERVICE_EXPORTERS             = (1 << 14),
-    SERVICE_ACLKSYNC              = (1 << 15)
+    SERVICE_REPLICATION           = (1 << 5),
+    SERVICE_WEB_SERVER            = (1 << 6),
+    SERVICE_ACLK                  = (1 << 7),
+    SERVICE_HEALTH                = (1 << 8),
+    SERVICE_STREAMING             = (1 << 9),
+    SERVICE_CONTEXT               = (1 << 10),
+    SERVICE_ANALYTICS             = (1 << 11),
+    SERVICE_EXPORTERS             = (1 << 12),
+    SERVICE_ACLKSYNC              = (1 << 13)
 } SERVICE_TYPE;
 
 typedef enum {