[receiver/mysql]: add scraping io_waits metrics

receiver/mysqlreceiver/client.go

@@ -26,6 +26,8 @@ type client interface {
 	Connect() error
 	getGlobalStats() (map[string]string, error)
 	getInnodbStats() (map[string]string, error)
+	getTableIoWaitsStats() ([]TableIoWaitsStats, error)
+	getIndexIoWaitsStats() ([]IndexIoWaitsStats, error)
 	Close() error
 }
 
@@ -34,6 +36,28 @@ type mySQLClient struct {
 	client  *sql.DB
 }
 
+type IoWaitsStats struct {
+	schema      string
+	name        string
+	countDelete int64
+	countFetch  int64
+	countInsert int64
+	countUpdate int64
+	timeDelete  int64
+	timeFetch   int64
+	timeInsert  int64
+	timeUpdate  int64
+}
+
+type TableIoWaitsStats struct {
+	IoWaitsStats
+}
+
+type IndexIoWaitsStats struct {
+	IoWaitsStats
+	index string
+}
+
 var _ client = (*mySQLClient)(nil)
 
 func newMySQLClient(conf *Config) client {
@@ -73,6 +97,61 @@ func (c *mySQLClient) getInnodbStats() (map[string]string, error) {
 	return Query(*c, query)
 }
 
+// getTableIoWaitsStats queries the db for table_io_waits metrics.
+func (c *mySQLClient) getTableIoWaitsStats() ([]TableIoWaitsStats, error) {
+	query := "SELECT OBJECT_SCHEMA, OBJECT_NAME, " +
+		"COUNT_DELETE, COUNT_FETCH, COUNT_INSERT, COUNT_UPDATE," +
+		"SUM_TIMER_DELETE, SUM_TIMER_FETCH, SUM_TIMER_INSERT, SUM_TIMER_UPDATE" +
+		"FROM performance_schema.table_io_waits_summary_by_table" +
+		"WHERE OBJECT_SCHEMA NOT IN ('mysql', 'performance_schema');"
+	rows, err := c.client.Query(query)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var stats []TableIoWaitsStats
+	for rows.Next() {
+		var s TableIoWaitsStats
+		err := rows.Scan(&s.schema, &s.name,
+			&s.countDelete, &s.countFetch, &s.countInsert, &s.countUpdate,
+			&s.timeDelete, &s.timeFetch, &s.timeInsert, &s.timeUpdate)
+		if err != nil {
+			return nil, err
+		}
+		stats = append(stats, s)
+	}
+
+	return stats, nil
+}
+
+// getIndexIoWaitsStats queries the db for index_io_waits metrics.
+func (c *mySQLClient) getIndexIoWaitsStats() ([]IndexIoWaitsStats, error) {
+	query := "SELECT OBJECT_SCHEMA, OBJECT_NAME, ifnull(INDEX_NAME, 'NONE') as INDEX_NAME," +
+		"COUNT_FETCH, COUNT_INSERT, COUNT_UPDATE, COUNT_DELETE," +
+		"SUM_TIMER_FETCH, SUM_TIMER_INSERT, SUM_TIMER_UPDATE, SUM_TIMER_DELETE" +
+		"FROM performance_schema.table_io_waits_summary_by_index_usage" +
+		"WHERE OBJECT_SCHEMA NOT IN ('mysql', 'performance_schema');"
+
+	rows, err := c.client.Query(query)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var stats []IndexIoWaitsStats
+	for rows.Next() {
+		var s IndexIoWaitsStats
+		err := rows.Scan(&s.schema, &s.name, &s.index,
+			&s.countDelete, &s.countFetch, &s.countInsert, &s.countUpdate,
+			&s.timeDelete, &s.timeFetch, &s.timeInsert, &s.timeUpdate)
+		if err != nil {
+			return nil, err
+		}
+		stats = append(stats, s)
+	}
+
+	return stats, nil
+}
+
 func Query(c mySQLClient, query string) (map[string]string, error) {
 	rows, err := c.client.Query(query)
 	if err != nil {

receiver/mysqlreceiver/documentation.md

@@ -17,13 +17,17 @@ These are the metrics available for this scraper.
 | **mysql.commands** | The number of times each type of command has been executed. | 1 | Sum(Int) | <ul> <li>command</li> </ul> |
 | **mysql.double_writes** | The number of writes to the InnoDB doublewrite buffer. | 1 | Sum(Int) | <ul> <li>double_writes</li> </ul> |
 | **mysql.handlers** | The number of requests to various MySQL handlers. | 1 | Sum(Int) | <ul> <li>handler</li> </ul> |
+| **mysql.index.io.wait.count** | The total count of I/O wait events for an index. | 1 | Sum(Int) | <ul> <li>io_waits_operations</li> <li>table_name</li> <li>schema</li> <li>index_name</li> </ul> |
+| **mysql.index.io.wait.time** | The total time of I/O wait events for an index. | ns | Sum(Int) | <ul> <li>io_waits_operations</li> <li>table_name</li> <li>schema</li> <li>index_name</li> </ul> |
 | **mysql.locks** | The number of MySQL locks. | 1 | Sum(Int) | <ul> <li>locks</li> </ul> |
 | **mysql.log_operations** | The number of InnoDB log operations. | 1 | Sum(Int) | <ul> <li>log_operations</li> </ul> |
 | **mysql.operations** | The number of InnoDB operations. | 1 | Sum(Int) | <ul> <li>operations</li> </ul> |
 | **mysql.page_operations** | The number of InnoDB page operations. | 1 | Sum(Int) | <ul> <li>page_operations</li> </ul> |
 | **mysql.row_locks** | The number of InnoDB row locks. | 1 | Sum(Int) | <ul> <li>row_locks</li> </ul> |
 | **mysql.row_operations** | The number of InnoDB row operations. | 1 | Sum(Int) | <ul> <li>row_operations</li> </ul> |
 | **mysql.sorts** | The number of MySQL sorts. | 1 | Sum(Int) | <ul> <li>sorts</li> </ul> |
+| **mysql.table.io.wait.count** | The total count of I/O wait events for a table. | 1 | Sum(Int) | <ul> <li>io_waits_operations</li> <li>table_name</li> <li>schema</li> </ul> |
+| **mysql.table.io.wait.time** | The total time of I/O wait events for a table. | ns | Sum(Int) | <ul> <li>io_waits_operations</li> <li>table_name</li> <li>schema</li> </ul> |
 | **mysql.threads** | The state of MySQL threads. | 1 | Sum(Int) | <ul> <li>threads</li> </ul> |
 
 **Highlighted metrics** are emitted by default. Other metrics are optional and not emitted by default.
@@ -51,11 +55,15 @@ metrics:
 | command (command) | The command types. | execute, close, fetch, prepare, reset, send_long_data |
 | double_writes (kind) | The doublewrite types. | pages_written, writes |
 | handler (kind) | The handler types. | commit, delete, discover, external_lock, mrr_init, prepare, read_first, read_key, read_last, read_next, read_prev, read_rnd, read_rnd_next, rollback, savepoint, savepoint_rollback, update, write |
+| index_name (index) | The name of the index. |  |
+| io_waits_operations (operation) | The io_waits operation type. | delete, fetch, insert, update |
 | locks (kind) | The table locks type. | immediate, waited |
 | log_operations (operation) | The log operation types. | waits, write_requests, writes |
 | operations (operation) | The operation types. | fsyncs, reads, writes |
 | page_operations (operation) | The page operation types. | created, read, written |
 | row_locks (kind) | The row lock type. | waits, time |
 | row_operations (operation) | The row operation type. | deleted, inserted, read, updated |
+| schema (schema) | The schema of the object. |  |
 | sorts (kind) | The sort count type. | merge_passes, range, rows, scan |
+| table_name (table) | Table name for event or process. |  |
 | threads (kind) | The thread count type. | cached, connected, created, running |