Boost dbengine (#14832)

* configure extent cache size

* workers can now execute up to 10 jobs in a run, boosting query prep and extent reads

* fix dispatched and executing counters

* boost to the max

* increase libuv worker threads

* query prep always get more prio than extent reads; stop processing in batch when dbengine is queue is critical

* fix accounting of query prep

* inlining of time-grouping functions, to speed up queries with billions of points

* make switching based on a local const variable

* print one pending contexts loading message per iteration

* inlined store engine query API

* inlined storage engine data collection api

* inlined all storage engine query ops

* eliminate and inline data collection ops

* simplified query group-by

* more error handling

* optimized partial trimming of group-by queries

* preparative work to support multiple passes of group-by

* more preparative work to support multiple passes of group-by (accepts multiple group-by params)

* unified query timings

* unified query timings - weights endpoint

* query target is no longer a static thread variable - there is a list of cached query targets, each of which of freed every 1000 queries

* fix query memory accounting

* added summary.dimension[].pri and sorted summary.dimensions based on priority and then name

* limit max ACLK WEB response size to 30MB

* the response type should be text/plain

* more preparative work for multiple group-by passes

* create functions for generating group by keys, ids and names

* multiple group-by passes are now supported

* parse group-by options array also with an index

* implemented percentage-of-instance group by function

* family is now merged in multi-node contexts

* prevent uninitialized use

1 files changed, 18 insertions, 6 deletions

diff --git a/web/api/queries/query.h b/web/api/queries/query.h
index a545d3d39a..e6fdcfbe4f 100644
--- a/web/api/queries/query.h
+++ b/web/api/queries/query.h
@@ -17,7 +17,7 @@ typedef enum rrdr_time_grouping {
     RRDR_GROUPING_TRIMMED_MEAN1,
     RRDR_GROUPING_TRIMMED_MEAN2,
     RRDR_GROUPING_TRIMMED_MEAN3,
-    RRDR_GROUPING_TRIMMED_MEAN5,
+    RRDR_GROUPING_TRIMMED_MEAN,
     RRDR_GROUPING_TRIMMED_MEAN10,
     RRDR_GROUPING_TRIMMED_MEAN15,
     RRDR_GROUPING_TRIMMED_MEAN20,
@@ -36,7 +36,7 @@ typedef enum rrdr_time_grouping {
     RRDR_GROUPING_PERCENTILE75,
     RRDR_GROUPING_PERCENTILE80,
     RRDR_GROUPING_PERCENTILE90,
-    RRDR_GROUPING_PERCENTILE95,
+    RRDR_GROUPING_PERCENTILE,
     RRDR_GROUPING_PERCENTILE97,
     RRDR_GROUPING_PERCENTILE98,
     RRDR_GROUPING_PERCENTILE99,
@@ -56,20 +56,32 @@ typedef enum rrdr_group_by {
     RRDR_GROUP_BY_NONE      = 0,
     RRDR_GROUP_BY_SELECTED  = (1 << 0),
     RRDR_GROUP_BY_DIMENSION = (1 << 1),
-    RRDR_GROUP_BY_NODE      = (1 << 2),
-    RRDR_GROUP_BY_INSTANCE  = (1 << 3),
-    RRDR_GROUP_BY_LABEL     = (1 << 4),
+    RRDR_GROUP_BY_INSTANCE  = (1 << 2),
+    RRDR_GROUP_BY_LABEL     = (1 << 3),
+    RRDR_GROUP_BY_NODE      = (1 << 4),
     RRDR_GROUP_BY_CONTEXT   = (1 << 5),
     RRDR_GROUP_BY_UNITS     = (1 << 6),
+    RRDR_GROUP_BY_PERCENTAGE_OF_INSTANCE  = (1 << 7),
 } RRDR_GROUP_BY;
 
+#define SUPPORTED_GROUP_BY_METHODS (\
+    RRDR_GROUP_BY_SELECTED  |\
+    RRDR_GROUP_BY_DIMENSION |\
+    RRDR_GROUP_BY_INSTANCE  |\
+    RRDR_GROUP_BY_LABEL     |\
+    RRDR_GROUP_BY_NODE      |\
+    RRDR_GROUP_BY_CONTEXT   |\
+    RRDR_GROUP_BY_UNITS     |\
+    RRDR_GROUP_BY_PERCENTAGE_OF_INSTANCE \
+)
+
 struct web_buffer;
 
 RRDR_GROUP_BY group_by_parse(char *s);
 void buffer_json_group_by_to_array(struct web_buffer *wb, RRDR_GROUP_BY group_by);
 
 typedef enum rrdr_group_by_function {
-    RRDR_GROUP_BY_FUNCTION_AVERAGE,
+    RRDR_GROUP_BY_FUNCTION_AVERAGE = 0,
     RRDR_GROUP_BY_FUNCTION_MIN,
     RRDR_GROUP_BY_FUNCTION_MAX,
     RRDR_GROUP_BY_FUNCTION_SUM,