Databend Query Metrics

A databend-query server records metrics in table system.metrics.

The metric_api_address to listen on that can be scraped by Prometheus and will return a prometheus format of metrics.

Note: Default metric_api_address value is : 127.0.0.1:7070 , Prometheus can access this uri: http://127.0.0.1:7070/metrics

MySQL> DESC system.metrics;
+--------+---------+------+---------+-------+
| Field  | Type    | Null | Default | Extra |
+--------+---------+------+---------+-------+
| metric | VARCHAR | NO   |         |       |
| kind   | VARCHAR | NO   |         |       |
| labels | VARCHAR | NO   |         |       |
| value  | VARCHAR | NO   |         |       |
+--------+---------+------+---------+-------+

Metrics has four attributes: metric, kind, labels, value.

metric indicate the name of the metric contained in the databend-query.

kind records the kind of metric. Available kinds:

counter
gauge
summary
untyped is part of summary

labels records the label of metric.

value records the value of metric.

Metrics

信息

Databend uses summary metrics to keep track of the total time spent handling various requests. Value quantile contains: [0.0, 0.5, 0.9, 0.99, 0.999].

metric	kind	description	labels
cluster_discovered_node_gauge	gauge	The number of nodes discovered in the current cluster.	tenant_id, cluster_id, flight_address and local_id(a inner cluster unique id)
interpreter_usedtime	summary	Sql interpreter used time.
meta_grpc_client_request_duration_ms	summary	The time used for requesting the remote meta service.	endpoint, request
meta_grpc_client_request_inflight	gauge	The currently on going request to remote meta service.
meta_grpc_client_request_success	counter	The total amount for successful request to remote meta service.
mysql_process_request_duration	summary	MySQL interactive process request used.
opendal_bytes_total	counter	The total data size opendal handled in byte.	operation, service
opendal_errors_total	counter	The total error count of opendal operations.	operation, service
opendal_failures_total	counter	The total failure count of opendal operations.	operation, service
opendal_requests_duration_seconds	summary	The time used by opendal to request remote storage backend.	operation, service
opendal_requests_total	counter	The total count of opendal operations.	operation, service
query_duration_ms	summary	The time used by each single query.	tenant, cluster, handler, kind
query_result_bytes	counter	The total returned data size of query result in byte.	tenant, cluster, handler, kind
query_result_rows	counter	The total returned data rows of query result.	tenant, cluster, handler, kind
query_scan_bytes	counter	The total scanned data size by query in byte.	tenant, cluster, handler, kind
query_scan_io_bytes	counter	The total scanned transferred data size by query in byte.	tenant, cluster, handler, kind
query_scan_partitions	counter	The total scanned partitions by query.	tenant, cluster, handler, kind
query_scan_rows	counter	The total scanned data rows by query.	tenant, cluster, handler, kind
query_start	counter	The total count of query started.	tenant, cluster, handler, kind
query_success	counter	The total count of query succeeded.	tenant, cluster, handler, kind
query_total_partitions	counter	The total partitions for query.	tenant, cluster, handler, kind
query_write_bytes	counter	The total data size written by query in byte.	tenant, cluster, handler, kind
query_write_io_bytes	counter	The total data size written and transferred by query in byte.	tenant, cluster, handler, kind
query_write_rows	counter	The total data rows written by query.	tenant, cluster, handler, kind
session_close_numbers	counter	The number of sessions have been disconnected since the server was started.	tenant, cluster_name
session_connect_numbers	counter	The number of sessions have been connected since the server was started.	tenant, cluster_name

Metrics​

Metrics