1 files changed, 87 insertions, 0 deletions
diff --git a/src/go/collectors/go.d.plugin/modules/mysql/collect_process_list.go b/src/go/collectors/go.d.plugin/modules/mysql/collect_process_list.go
new file mode 100644
index 000000000..08c08c6d5
--- /dev/null
+++ b/src/go/collectors/go.d.plugin/modules/mysql/collect_process_list.go
@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package mysql
+
+import (
+	"github.com/blang/semver/v4"
+)
+
+// Table Schema:
+// (MariaDB) https://mariadb.com/kb/en/information-schema-processlist-table/
+// (MySql) https://dev.mysql.com/doc/refman/5.7/en/information-schema-processlist-table.html
+const (
+	queryShowProcessList = `
+SELECT 
+  time, 
+  user 
+FROM 
+  information_schema.processlist 
+WHERE 
+  info IS NOT NULL 
+  AND info NOT LIKE '%PROCESSLIST%' 
+ORDER BY 
+  time;`
+)
+
+// Performance Schema
+// (MySQL) https://dev.mysql.com/doc/refman/8.0/en/performance-schema-processlist-table.html
+const (
+	queryShowProcessListPS = `
+SELECT 
+  time, 
+  user 
+FROM 
+  performance_schema.processlist 
+WHERE 
+  info IS NOT NULL 
+  AND info NOT LIKE '%PROCESSLIST%' 
+ORDER BY 
+  time;`
+)
+
+func (m *MySQL) collectProcessListStatistics(mx map[string]int64) error {
+	var q string
+	mysqlMinVer := semver.Version{Major: 8, Minor: 0, Patch: 22}
+	if !m.isMariaDB && m.version.GTE(mysqlMinVer) && m.varPerformanceSchema == "ON" {
+		q = queryShowProcessListPS
+	} else {
+		q = queryShowProcessList
+	}
+	m.Debugf("executing query: '%s'", q)
+
+	var maxTime int64 // slowest query milliseconds in process list
+
+	duration, err := m.collectQuery(q, func(column, value string, _ bool) {
+		switch column {
+		case "time":
+			maxTime = parseInt(value)
+		case "user":
+			// system user refers to non-client threads
+			// event_scheduler is the thread used to monitor scheduled events
+			// system user and event_scheduler threads are grouped as system/database threads
+			// authenticated and unauthenticated user are grouped as users
+			// please see USER section in
+			// https://dev.mysql.com/doc/refman/8.0/en/information-schema-processlist-table.html
+			switch value {
+			case "system user", "event_scheduler":
+				mx["process_list_queries_count_system"] += 1
+			default:
+				mx["process_list_queries_count_user"] += 1
+			}
+		}
+	})
+	if err != nil {
+		return err
+	}
+
+	if _, ok := mx["process_list_queries_count_system"]; !ok {
+		mx["process_list_queries_count_system"] = 0
+	}
+	if _, ok := mx["process_list_queries_count_user"]; !ok {
+		mx["process_list_queries_count_user"] = 0
+	}
+	mx["process_list_fetch_query_duration"] = duration
+	mx["process_list_longest_query_duration"] = maxTime
+
+	return nil
+}