Add a thread to asynchronously process metadata updates (#13783)

* Remove old metalog text fle processing

* Add metadata event loop

* Move functions from sqlite_functions.c to sqlite_metadata.c
Queue updates to the metadata event loop
Migration to remove unused tables
Cleanup unused functions

* Queue chart labels to metadata

* Store chart labels to metadata

* During shutdown, run full speed

* Add shutdown prepare
Handle SHUTDOWN in the cmd queue function
Add worker thread to handle host/chart/dimension metadata doing dictionary traversals

* Remove unused RRDIM_FLAG_ACLK
Add flags to trigger host/chart/dimension metadata processing

* Incremental processing of chart metadata writes

* Store host labels

* Remove redundant return statements

* Change unit tests / cleanup

* Fix rescheduling

* Schedule chart labels update by setting the RRDSET_FLAG_METADATA_UPDATE flag

* Queue commands to update metadata for dimension and host labels

* Make sure we do a final scan to store metadata during shutdown (if needed)

* Remove unused structures
Adjust queue size since we do batch processing of updates without queueing individual messages
Remove pragma mmap for now
Fix memory leak during sqlite unittest (minor)

* Dont update if we are in archive mode

* Cleanup

* Build entire message payload and store

* Initialize worker completion properly

* Properly skip host check for pending metadata updates

* Report bind param failures
Add worker request inside the data payload
Initialize variables to silence warnings
Rebase on master

* Report the chart id (not the dimension) and the dimension id when storing a dimension

* Compilation warnings in 32bit

* Add DEFINE for the queries

* Remove commented out code

* * Remove items parameter from unitest
* Remove commented out code
* sqlite_metadata.h contains only public items
* Use sleep_usec instead of usleep
* Rename metadata_database_init_cmd_queue to metadata_init_cmd_queue
* Rename metadata_database_enq_cmd_noblock to metadata_enq_cmd_noblock

4 files changed, 9 insertions, 1 deletions

diff --git a/daemon/global_statistics.c b/daemon/global_statistics.c
index 62997cb785..32b885738c 100644
--- a/daemon/global_statistics.c
+++ b/daemon/global_statistics.c
@@ -1832,6 +1832,7 @@ static struct worker_utilization all_workers_utilization[] = {
     { .name = "WEB",         .family = "workers web server",              .priority = 1000000 },
     { .name = "ACLKQUERY",   .family = "workers aclk query",              .priority = 1000000 },
     { .name = "ACLKSYNC",    .family = "workers aclk host sync",          .priority = 1000000 },
+    { .name = "METASYNC",    .family = "workers metadata sync",           .priority = 1000000 },
     { .name = "PLUGINSD",    .family = "workers plugins.d",               .priority = 1000000 },
     { .name = "STATSD",      .family = "workers plugin statsd",           .priority = 1000000 },
     { .name = "STATSDFLUSH", .family = "workers plugin statsd flush",     .priority = 1000000 },
diff --git a/daemon/main.c b/daemon/main.c
index df93bfa25b..2bd8be8a48 100644
--- a/daemon/main.c
+++ b/daemon/main.c
@@ -60,7 +60,9 @@ void netdata_cleanup_and_exit(int ret) {
                 rrdeng_prepare_exit(multidb_ctx[tier]);
         }
 #endif
+        metadata_sync_shutdown_prepare();
         rrdhost_free_all();
+        metadata_sync_shutdown();
 #ifdef ENABLE_DBENGINE
         if(dbengine_enabled) {
             for (int tier = 0; tier < storage_tiers; tier++)
@@ -1039,6 +1041,9 @@ int main(int argc, char **argv) {
                         else if(strcmp(optarg, "rrdlabelstest") == 0) {
                             return rrdlabels_unittest();
                         }
+                        else if(strcmp(optarg, "metatest") == 0) {
+                            return metadata_unittest();
+                        }
                         else if(strncmp(optarg, createdataset_string, strlen(createdataset_string)) == 0) {
                             optarg += strlen(createdataset_string);
                             unsigned history_seconds = strtoul(optarg, NULL, 0);
diff --git a/daemon/service.c b/daemon/service.c
index 3a267402d1..a45019813a 100644
--- a/daemon/service.c
+++ b/daemon/service.c
@@ -60,7 +60,7 @@ static void svc_rrddim_obsolete_to_archive(RRDDIM *rd) {
 
         if (tiers_available == tiers_said_yes && tiers_said_yes) {
             /* This metric has no data and no references */
-            delete_dimension_uuid(&rd->metric_uuid);
+            metaqueue_delete_dimension_uuid(&rd->metric_uuid);
         }
         else {
             /* Do not delete this dimension */
diff --git a/daemon/unit_test.c b/daemon/unit_test.c
index 4d61c18984..32ebb2996c 100644
--- a/daemon/unit_test.c
+++ b/daemon/unit_test.c
@@ -1564,8 +1564,10 @@ int test_sqlite(void) {
 
     buffer_free(sql);
     fprintf(stderr,"SQLite is OK\n");
+    rc = sqlite3_close_v2(db_meta);
     return 0;
 error:
+    rc = sqlite3_close_v2(db_meta);
     fprintf(stderr,"SQLite statement failed: %s\n", buffer_tostring(sql));
     buffer_free(sql);
     fprintf(stderr,"SQLite tests failed\n");