SQL Datasources: Update Max Connection and Max Idle Connection Defaults to 100 and add auto mode (#65834)

* Update connection configuration for SQL datasources

* Working auto state for connection numbers

* Add migration

* Use defaults from constants file

* Remove dead code

* Add tests and restructure useMigrateDatabaseField

* Update function names

* Update docs

* Make sure we don't continually issue updates

* Update docs

* Use onOptionsChnage in ConnectionLimits

* Update docs

* Clean up docs

* Update migration

* Fix default values in docs

* Fix spacing issue

* Fix test

* Update default values for SQL connections

* Include consts

* Allow override for default SQL datasource connection parameters

* Fix linter errors

* Remove extra @ts-ignore

* Centralize logic for default values

* Remove debugging

* Remove unecessary function

* Update configuration docs

* minor suggested change

* Fix comment misspelling

* Remove unecessary default setting code

* Update docs to indicate that code was included for backport version

* Remove dead code

---------

Co-authored-by: lwandz13 <larissa.wandzura@grafana.com>

pkg/setting/setting.go

@@ -369,6 +369,11 @@ type Cfg struct {
 	// Data sources
 	DataSourceLimit int
 
+	// SQL Data sources
+	SqlDatasourceMaxOpenConnsDefault    int
+	SqlDatasourceMaxIdleConnsDefault    int
+	SqlDatasourceMaxConnLifetimeDefault int
+
 	// Snapshots
 	SnapshotEnabled       bool
 	ExternalSnapshotUrl   string
@@ -1116,6 +1121,7 @@ func (cfg *Cfg) Load(args CommandLineArgs) error {
 	}
 
 	cfg.readDataSourcesSettings()
+	cfg.readSqlDataSourceSettings()
 
 	cfg.Storage = readStorageSettings(iniFile)
 	cfg.Search = readSearchSettings(iniFile)
@@ -1848,6 +1854,13 @@ func (cfg *Cfg) readDataSourcesSettings() {
 	cfg.DataSourceLimit = datasources.Key("datasource_limit").MustInt(5000)
 }
 
+func (cfg *Cfg) readSqlDataSourceSettings() {
+	sqlDatasources := cfg.Raw.Section("sql_datasources")
+	cfg.SqlDatasourceMaxOpenConnsDefault = sqlDatasources.Key("max_open_conns_default").MustInt(100)
+	cfg.SqlDatasourceMaxIdleConnsDefault = sqlDatasources.Key("max_idle_conns_default").MustInt(100)
+	cfg.SqlDatasourceMaxConnLifetimeDefault = sqlDatasources.Key("max_conn_lifetime_default").MustInt(14400)
+}
+
 func GetAllowedOriginGlobs(originPatterns []string) ([]glob.Glob, error) {
 	allowedOrigins := originPatterns
 	originGlobs := make([]glob.Glob, 0, len(allowedOrigins))

pkg/tsdb/mssql/mssql.go

@@ -56,9 +56,9 @@ func (s *Service) QueryData(ctx context.Context, req *backend.QueryDataRequest)
 func newInstanceSettings(cfg *setting.Cfg) datasource.InstanceFactoryFunc {
 	return func(settings backend.DataSourceInstanceSettings) (instancemgmt.Instance, error) {
 		jsonData := sqleng.JsonData{
-			MaxOpenConns:      0,
-			MaxIdleConns:      2,
-			ConnMaxLifetime:   14400,
+			MaxOpenConns:      cfg.SqlDatasourceMaxOpenConnsDefault,
+			MaxIdleConns:      cfg.SqlDatasourceMaxIdleConnsDefault,
+			ConnMaxLifetime:   cfg.SqlDatasourceMaxConnLifetimeDefault,
 			Encrypt:           "false",
 			ConnectionTimeout: 0,
 			SecureDSProxy:     false,

pkg/tsdb/mysql/mysql.go

@@ -52,9 +52,9 @@ func ProvideService(cfg *setting.Cfg, httpClientProvider httpclient.Provider) *S
 func newInstanceSettings(cfg *setting.Cfg, httpClientProvider httpclient.Provider) datasource.InstanceFactoryFunc {
 	return func(settings backend.DataSourceInstanceSettings) (instancemgmt.Instance, error) {
 		jsonData := sqleng.JsonData{
-			MaxOpenConns:    0,
-			MaxIdleConns:    2,
-			ConnMaxLifetime: 14400,
+			MaxOpenConns:    cfg.SqlDatasourceMaxOpenConnsDefault,
+			MaxIdleConns:    cfg.SqlDatasourceMaxIdleConnsDefault,
+			ConnMaxLifetime: cfg.SqlDatasourceMaxConnLifetimeDefault,
 			SecureDSProxy:   false,
 		}
 

pkg/tsdb/postgres/postgres.go

@@ -56,9 +56,9 @@ func (s *Service) newInstanceSettings(cfg *setting.Cfg) datasource.InstanceFacto
 	return func(settings backend.DataSourceInstanceSettings) (instancemgmt.Instance, error) {
 		logger.Debug("Creating Postgres query endpoint")
 		jsonData := sqleng.JsonData{
-			MaxOpenConns:        0,
-			MaxIdleConns:        2,
-			ConnMaxLifetime:     14400,
+			MaxOpenConns:        cfg.SqlDatasourceMaxOpenConnsDefault,
+			MaxIdleConns:        cfg.SqlDatasourceMaxIdleConnsDefault,
+			ConnMaxLifetime:     cfg.SqlDatasourceMaxConnLifetimeDefault,
 			Timescaledb:         false,
 			ConfigurationMethod: "file-path",
 			SecureDSProxy:       false,

pkg/tsdb/sqleng/sql_engine.go

@@ -84,6 +84,13 @@ type DataSourceInfo struct {
 	DecryptedSecureJSONData map[string]string
 }
 
+// Defaults for the xorm connection pool
+type DefaultConnectionInfo struct {
+	MaxOpenConns    int
+	MaxIdleConns    int
+	ConnMaxLifetime int
+}
+
 type DataPluginConfiguration struct {
 	DriverName        string
 	DSInfo            DataSourceInfo