From d5b2092702c21a957679c237837d34734479bcd0 Mon Sep 17 00:00:00 2001
From: macneale4 <46170177+macneale4@users.noreply.github.com>
Date: Tue, 25 Mar 2025 03:19:27 +0000
Subject: [PATCH 01/16] [ga-bump-dep] Bump dependency in Dolt by macneale4

---
 go/go.mod | 4 ++--
 go/go.sum | 8 ++++----
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/go/go.mod b/go/go.mod
index d853d3f1e67..ea9de6ce73f 100644
--- a/go/go.mod
+++ b/go/go.mod
@@ -14,7 +14,7 @@ require (
 	github.com/dolthub/fslock v0.0.3
 	github.com/dolthub/ishell v0.0.0-20240701202509-2b217167d718
 	github.com/dolthub/sqllogictest/go v0.0.0-20201107003712-816f3ae12d81
-	github.com/dolthub/vitess v0.0.0-20250320231804-0e77d549294c
+	github.com/dolthub/vitess v0.0.0-20250325024605-8131be3ca6d3
 	github.com/dustin/go-humanize v1.0.1
 	github.com/fatih/color v1.13.0
 	github.com/flynn-archive/go-shlex v0.0.0-20150515145356-3f9db97f8568
@@ -60,7 +60,7 @@ require (
 	github.com/creasty/defaults v1.6.0
 	github.com/dolthub/aws-sdk-go-ini-parser v0.0.0-20250305001723-2821c37f6c12
 	github.com/dolthub/flatbuffers/v23 v23.3.3-dh.2
-	github.com/dolthub/go-mysql-server v0.19.1-0.20250321183729-47285a54773c
+	github.com/dolthub/go-mysql-server v0.19.1-0.20250325031739-45c4c4ce0449
 	github.com/dolthub/gozstd v0.0.0-20240423170813-23a2903bca63
 	github.com/esote/minmaxheap v1.0.0
 	github.com/goccy/go-json v0.10.2
diff --git a/go/go.sum b/go/go.sum
index e84c69f9eb9..ea48af52a5a 100644
--- a/go/go.sum
+++ b/go/go.sum
@@ -221,8 +221,8 @@ github.com/dolthub/fslock v0.0.3 h1:iLMpUIvJKMKm92+N1fmHVdxJP5NdyDK5bK7z7Ba2s2U=
 github.com/dolthub/fslock v0.0.3/go.mod h1:QWql+P17oAAMLnL4HGB5tiovtDuAjdDTPbuqx7bYfa0=
 github.com/dolthub/go-icu-regex v0.0.0-20250319212010-451ea8d003fa h1:NFbzJ4wjWRz32nz2EimbrHpRx1Xt6k+IaR8N+j4x62k=
 github.com/dolthub/go-icu-regex v0.0.0-20250319212010-451ea8d003fa/go.mod h1:ylU4XjUpsMcvl/BKeRRMXSH7e7WBrPXdSLvnRJYrxEA=
-github.com/dolthub/go-mysql-server v0.19.1-0.20250321183729-47285a54773c h1:bCPelFSgt6aOPUqvrKV3OY8S9tjcBxQTgFNGARsrcSU=
-github.com/dolthub/go-mysql-server v0.19.1-0.20250321183729-47285a54773c/go.mod h1:WyimbJzsrNiYsQ7nfnXYLIoFAfNX0I7rHH1WaDt7faM=
+github.com/dolthub/go-mysql-server v0.19.1-0.20250325031739-45c4c4ce0449 h1:pW0XNR2cdUTGmLXyvFux5hZQRFJlHK12fWeC5vdmWNo=
+github.com/dolthub/go-mysql-server v0.19.1-0.20250325031739-45c4c4ce0449/go.mod h1:vKBT9NZQDwG0Db6CT4D92Mw6kaJpWbIDy1hBX7XWUCA=
 github.com/dolthub/gozstd v0.0.0-20240423170813-23a2903bca63 h1:OAsXLAPL4du6tfbBgK0xXHZkOlos63RdKYS3Sgw/dfI=
 github.com/dolthub/gozstd v0.0.0-20240423170813-23a2903bca63/go.mod h1:lV7lUeuDhH5thVGDCKXbatwKy2KW80L4rMT46n+Y2/Q=
 github.com/dolthub/ishell v0.0.0-20240701202509-2b217167d718 h1:lT7hE5k+0nkBdj/1UOSFwjWpNxf+LCApbRHgnCA17XE=
@@ -231,8 +231,8 @@ github.com/dolthub/jsonpath v0.0.2-0.20240227200619-19675ab05c71 h1:bMGS25NWAGTE
 github.com/dolthub/jsonpath v0.0.2-0.20240227200619-19675ab05c71/go.mod h1:2/2zjLQ/JOOSbbSboojeg+cAwcRV0fDLzIiWch/lhqI=
 github.com/dolthub/sqllogictest/go v0.0.0-20201107003712-816f3ae12d81 h1:7/v8q9XGFa6q5Ap4Z/OhNkAMBaK5YeuEzwJt+NZdhiE=
 github.com/dolthub/sqllogictest/go v0.0.0-20201107003712-816f3ae12d81/go.mod h1:siLfyv2c92W1eN/R4QqG/+RjjX5W2+gCTRjZxBjI3TY=
-github.com/dolthub/vitess v0.0.0-20250320231804-0e77d549294c h1:Dv2DfEGb8WRBi8I5KF5Sy39TuZi/FI692mpobKWcv4g=
-github.com/dolthub/vitess v0.0.0-20250320231804-0e77d549294c/go.mod h1:1gQZs/byeHLMSul3Lvl3MzioMtOW1je79QYGyi2fd70=
+github.com/dolthub/vitess v0.0.0-20250325024605-8131be3ca6d3 h1:euU+adNAYw46Zcp1HnoaSDWhqjfaL8s/1SPU+i16gYM=
+github.com/dolthub/vitess v0.0.0-20250325024605-8131be3ca6d3/go.mod h1:1gQZs/byeHLMSul3Lvl3MzioMtOW1je79QYGyi2fd70=
 github.com/dustin/go-humanize v0.0.0-20171111073723-bb3d318650d4/go.mod h1:HtrtbFcZ19U5GC7JDqmcUSB87Iq5E25KnS6fMYU6eOk=
 github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=
 github.com/dustin/go-humanize v1.0.1/go.mod h1:Mu1zIs6XwVuF/gI1OepvI0qD18qycQx+mFykh5fBlto=

From 115aec82d77281854a19c0322badac759f639560 Mon Sep 17 00:00:00 2001
From: Neil Macneale IV <neil@dolthub.com>
Date: Wed, 19 Mar 2025 15:40:36 -0700
Subject: [PATCH 02/16] Add support for back_log option to server config and
 flags.

No tests. No SQL support
---
 .../dolt/commands/sqlserver/command_line_config.go   | 12 ++++++++++++
 go/cmd/dolt/commands/sqlserver/server.go             |  1 +
 go/cmd/dolt/commands/sqlserver/sqlserver.go          |  4 ++++
 go/libraries/doltcore/servercfg/serverconfig.go      |  5 +++++
 go/libraries/doltcore/servercfg/yaml_config.go       | 12 ++++++++++++
 5 files changed, 34 insertions(+)

diff --git a/go/cmd/dolt/commands/sqlserver/command_line_config.go b/go/cmd/dolt/commands/sqlserver/command_line_config.go
index b90b1e1adb1..6c7de3887c7 100755
--- a/go/cmd/dolt/commands/sqlserver/command_line_config.go
+++ b/go/cmd/dolt/commands/sqlserver/command_line_config.go
@@ -42,6 +42,7 @@ type commandLineServerConfig struct {
 	autoCommit              bool
 	doltTransactionCommit   bool
 	maxConnections          uint64
+	maxWaitConnections      uint32
 	tlsKey                  string
 	tlsCert                 string
 	requireSecureTransport  bool
@@ -72,6 +73,7 @@ func DefaultCommandLineServerConfig() *commandLineServerConfig {
 		logFormat:               servercfg.DefaultLogFormat,
 		autoCommit:              servercfg.DefaultAutoCommit,
 		maxConnections:          servercfg.DefaultMaxConnections,
+		maxWaitConnections:      servercfg.DefaultMaxWaitConnections,
 		dataDir:                 servercfg.DefaultDataDir,
 		cfgDir:                  filepath.Join(servercfg.DefaultDataDir, servercfg.DefaultCfgDir),
 		privilegeFilePath:       filepath.Join(servercfg.DefaultDataDir, servercfg.DefaultCfgDir, servercfg.DefaultPrivilegeFilePath),
@@ -169,6 +171,10 @@ func NewCommandLineConfig(creds *cli.UserPassword, apr *argparser.ArgParseResult
 		config.withMaxConnections(uint64(maxConnections))
 	}
 
+	if maxWaitConnections, ok := apr.GetInt(maxWaitConnectionsFlag); ok {
+		config.maxWaitConnections = uint32(maxWaitConnections)
+	}
+
 	config.autoCommit = !apr.Contains(noAutoCommitFlag)
 	if apr.Contains(noAutoCommitFlag) {
 		config.valuesSet[servercfg.AutoCommitKey] = struct{}{}
@@ -258,6 +264,12 @@ func (cfg *commandLineServerConfig) MaxConnections() uint64 {
 	return cfg.maxConnections
 }
 
+// MaxWaitConnections returns the maximum number of simultaneous connections that the server will allow to block waiting
+// for a connection before new connections result in immediate rejection.
+func (cfg *commandLineServerConfig) MaxWaitConnections() uint32 {
+	return cfg.maxWaitConnections
+}
+
 // TLSKey returns a path to the servers PEM-encoded private TLS key. "" if there is none.
 func (cfg *commandLineServerConfig) TLSKey() string {
 	return cfg.tlsKey
diff --git a/go/cmd/dolt/commands/sqlserver/server.go b/go/cmd/dolt/commands/sqlserver/server.go
index 0f8087a9561..366c4af12c3 100644
--- a/go/cmd/dolt/commands/sqlserver/server.go
+++ b/go/cmd/dolt/commands/sqlserver/server.go
@@ -1092,6 +1092,7 @@ func getConfigFromServerConfig(serverConfig servercfg.ServerConfig, plf server.P
 	serverConf.ConnReadTimeout = readTimeout
 	serverConf.ConnWriteTimeout = writeTimeout
 	serverConf.MaxConnections = serverConfig.MaxConnections()
+	serverConf.MaxWaitConnections = serverConfig.MaxWaitConnections()
 	serverConf.TLSConfig = tlsConfig
 	serverConf.RequireSecureTransport = serverConfig.RequireSecureTransport()
 	serverConf.MaxLoggedQueryLen = serverConfig.MaxLoggedQueryLen()
diff --git a/go/cmd/dolt/commands/sqlserver/sqlserver.go b/go/cmd/dolt/commands/sqlserver/sqlserver.go
index 48f2df51538..402e698e667 100644
--- a/go/cmd/dolt/commands/sqlserver/sqlserver.go
+++ b/go/cmd/dolt/commands/sqlserver/sqlserver.go
@@ -48,6 +48,7 @@ const (
 	configFileFlag              = "config"
 	queryParallelismFlag        = "query-parallelism"
 	maxConnectionsFlag          = "max-connections"
+	maxWaitConnectionsFlag      = "back-log"
 	allowCleartextPasswordsFlag = "allow-cleartext-passwords"
 	socketFlag                  = "socket"
 	remotesapiPortFlag          = "remotesapi-port"
@@ -107,6 +108,8 @@ SUPPORTED CONFIG FILE FIELDS:
 
 {{.EmphasisLeft}}listener.max_connections{{.EmphasisRight}}: The number of simultaneous connections that the server will accept
 
+{{.EmphasisLeft}}listener.back_log{{.EmphasisRight}}: The number of simultaneous connections that the server will allow to block waiting for a connection before new connections result in immediate rejection. Default 50.
+
 {{.EmphasisLeft}}listener.read_timeout_millis{{.EmphasisRight}}: The number of milliseconds that the server will wait for a read operation
 
 {{.EmphasisLeft}}listener.write_timeout_millis{{.EmphasisRight}}: The number of milliseconds that the server will wait for a write operation
@@ -179,6 +182,7 @@ func (cmd SqlServerCmd) ArgParserWithName(name string) *argparser.ArgParser {
 	ap.SupportsFlag(noAutoCommitFlag, "", "Set @@autocommit = off for the server.")
 	ap.SupportsInt(queryParallelismFlag, "", "num-go-routines", "Deprecated, no effect in current versions of Dolt")
 	ap.SupportsInt(maxConnectionsFlag, "", "max-connections", fmt.Sprintf("Set the number of connections handled by the server. Defaults to `%d`.", serverConfig.MaxConnections()))
+	ap.SupportsInt(maxWaitConnectionsFlag, "", "back-log", fmt.Sprintf("Set the number of connections that can block waiting for a connection before new connections are rejected. Defaults to `%d`.", serverConfig.MaxWaitConnections()))
 	ap.SupportsString(commands.PrivsFilePathFlag, "", "privilege file", "Path to a file to load and store users and grants. Defaults to `$doltcfg-dir/privileges.db`. Will be created as needed.")
 	ap.SupportsString(commands.BranchCtrlPathFlag, "", "branch control file", "Path to a file to load and store branch control permissions. Defaults to `$doltcfg-dir/branch_control.db`. Will be created as needed.")
 	ap.SupportsString(allowCleartextPasswordsFlag, "", "allow-cleartext-passwords", "Allows use of cleartext passwords. Defaults to false.")
diff --git a/go/libraries/doltcore/servercfg/serverconfig.go b/go/libraries/doltcore/servercfg/serverconfig.go
index 2b48640387e..51c83d97ef4 100644
--- a/go/libraries/doltcore/servercfg/serverconfig.go
+++ b/go/libraries/doltcore/servercfg/serverconfig.go
@@ -59,6 +59,7 @@ const (
 	DefaultAutoGCBehaviorEnable    = false
 	DefaultDoltTransactionCommit   = false
 	DefaultMaxConnections          = 1000
+	DefaultMaxWaitConnections      = 50
 	DefaultDataDir                 = "."
 	DefaultCfgDir                  = ".doltcfg"
 	DefaultPrivilegeFilePath       = "privileges.db"
@@ -159,6 +160,9 @@ type ServerConfig interface {
 	CfgDir() string
 	// MaxConnections returns the maximum number of simultaneous connections the server will allow.  The default is 1
 	MaxConnections() uint64
+	// MaxWaitConnections returns the maximum number of simultaneous connections that the server will allow to block waiting
+	// for a connection before new connections result in immediate rejection
+	MaxWaitConnections() uint32
 	// TLSKey returns a path to the servers PEM-encoded private TLS key. "" if there is none.
 	TLSKey() string
 	// TLSCert returns a path to the servers PEM-encoded TLS certificate chain. "" if there is none.
@@ -240,6 +244,7 @@ func defaultServerConfigYAML() *YAMLConfig {
 			HostStr:                 ptr(DefaultHost),
 			PortNumber:              ptr(DefaultPort),
 			MaxConnections:          ptr(uint64(DefaultMaxConnections)),
+			BackLog:                 ptr(uint32(DefaultMaxWaitConnections)),
 			ReadTimeoutMillis:       ptr(uint64(DefaultTimeout)),
 			WriteTimeoutMillis:      ptr(uint64(DefaultTimeout)),
 			AllowCleartextPasswords: ptr(DefaultAllowCleartextPasswords),
diff --git a/go/libraries/doltcore/servercfg/yaml_config.go b/go/libraries/doltcore/servercfg/yaml_config.go
index c5bfe483033..21afacf29a7 100644
--- a/go/libraries/doltcore/servercfg/yaml_config.go
+++ b/go/libraries/doltcore/servercfg/yaml_config.go
@@ -80,6 +80,7 @@ type ListenerYAMLConfig struct {
 	HostStr            *string `yaml:"host,omitempty"`
 	PortNumber         *int    `yaml:"port,omitempty"`
 	MaxConnections     *uint64 `yaml:"max_connections,omitempty"`
+	BackLog            *uint32 `yaml:"back_log,omitempty"`
 	ReadTimeoutMillis  *uint64 `yaml:"read_timeout_millis,omitempty"`
 	WriteTimeoutMillis *uint64 `yaml:"write_timeout_millis,omitempty"`
 	// TLSKey is a file system path to an unencrypted private TLS key in PEM format.
@@ -487,6 +488,9 @@ func (cfg YAMLConfig) withDefaultsFilledIn() YAMLConfig {
 	if withDefaults.ListenerConfig.MaxConnections == nil {
 		withDefaults.ListenerConfig.MaxConnections = defaults.ListenerConfig.MaxConnections
 	}
+	if withDefaults.ListenerConfig.BackLog == nil {
+		withDefaults.ListenerConfig.BackLog = defaults.ListenerConfig.BackLog
+	}
 	if withDefaults.ListenerConfig.ReadTimeoutMillis == nil {
 		withDefaults.ListenerConfig.ReadTimeoutMillis = defaults.ListenerConfig.ReadTimeoutMillis
 	}
@@ -659,6 +663,14 @@ func (cfg YAMLConfig) MaxConnections() uint64 {
 	return *cfg.ListenerConfig.MaxConnections
 }
 
+func (cfg YAMLConfig) MaxWaitConnections() uint32 {
+	if cfg.ListenerConfig.BackLog == nil {
+		return DefaultMaxWaitConnections
+	}
+
+	return *cfg.ListenerConfig.BackLog
+}
+
 // DisableClientMultiStatements returns true if the server should run in a mode
 // where the CLIENT_MULTI_STATEMENTS option are ignored and every incoming
 // ComQuery packet is assumed to be a standalone query.

From 309ba1d3d44926aa5cd20b97b826d497af938cf0 Mon Sep 17 00:00:00 2001
From: Neil Macneale IV <neil@dolthub.com>
Date: Wed, 19 Mar 2025 16:26:56 -0700
Subject: [PATCH 03/16] Test the --back-log value gets written to config.yaml

---
 go/cmd/dolt/commands/sqlserver/command_line_config.go     | 8 +++++++-
 go/libraries/doltcore/servercfg/serverconfig.go           | 1 +
 go/libraries/doltcore/servercfg/yaml_config.go            | 4 ++++
 .../bats/sql-server-config-file-generation.bats           | 2 ++
 4 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/go/cmd/dolt/commands/sqlserver/command_line_config.go b/go/cmd/dolt/commands/sqlserver/command_line_config.go
index 6c7de3887c7..05eff0cf7f6 100755
--- a/go/cmd/dolt/commands/sqlserver/command_line_config.go
+++ b/go/cmd/dolt/commands/sqlserver/command_line_config.go
@@ -172,7 +172,7 @@ func NewCommandLineConfig(creds *cli.UserPassword, apr *argparser.ArgParseResult
 	}
 
 	if maxWaitConnections, ok := apr.GetInt(maxWaitConnectionsFlag); ok {
-		config.maxWaitConnections = uint32(maxWaitConnections)
+		config.withMaxWaitConnections(uint32(maxWaitConnections))
 	}
 
 	config.autoCommit = !apr.Contains(noAutoCommitFlag)
@@ -437,6 +437,12 @@ func (cfg *commandLineServerConfig) withMaxConnections(maxConnections uint64) *c
 	return cfg
 }
 
+func (cfg *commandLineServerConfig) withMaxWaitConnections(maxWaitConnections uint32) *commandLineServerConfig {
+	cfg.maxWaitConnections = maxWaitConnections
+	cfg.valuesSet[servercfg.MaxWaitConnectionsKey] = struct{}{}
+	return cfg
+}
+
 // withDataDir updates the path to a directory to use as the data dir.
 func (cfg *commandLineServerConfig) withDataDir(dataDir string) *commandLineServerConfig {
 	cfg.dataDir = dataDir
diff --git a/go/libraries/doltcore/servercfg/serverconfig.go b/go/libraries/doltcore/servercfg/serverconfig.go
index 51c83d97ef4..d12fc16a7c0 100644
--- a/go/libraries/doltcore/servercfg/serverconfig.go
+++ b/go/libraries/doltcore/servercfg/serverconfig.go
@@ -311,6 +311,7 @@ const (
 	DataDirKey                      = "data_dir"
 	CfgDirKey                       = "cfg_dir"
 	MaxConnectionsKey               = "max_connections"
+	MaxWaitConnectionsKey           = "back_log"
 	TLSKeyKey                       = "tls_key"
 	TLSCertKey                      = "tls_cert"
 	RequireSecureTransportKey       = "require_secure_transport"
diff --git a/go/libraries/doltcore/servercfg/yaml_config.go b/go/libraries/doltcore/servercfg/yaml_config.go
index 21afacf29a7..664d68e04a4 100644
--- a/go/libraries/doltcore/servercfg/yaml_config.go
+++ b/go/libraries/doltcore/servercfg/yaml_config.go
@@ -198,6 +198,7 @@ func ServerConfigAsYAMLConfig(cfg ServerConfig) *YAMLConfig {
 			HostStr:                 ptr(cfg.Host()),
 			PortNumber:              ptr(cfg.Port()),
 			MaxConnections:          ptr(cfg.MaxConnections()),
+			BackLog:                 ptr(cfg.MaxWaitConnections()),
 			ReadTimeoutMillis:       ptr(cfg.ReadTimeout()),
 			WriteTimeoutMillis:      ptr(cfg.WriteTimeout()),
 			TLSKey:                  nillableStrPtr(cfg.TLSKey()),
@@ -268,6 +269,7 @@ func ServerConfigSetValuesAsYAMLConfig(cfg ServerConfig) *YAMLConfig {
 			HostStr:                 zeroIf(ptr(cfg.Host()), !cfg.ValueSet(HostKey)),
 			PortNumber:              zeroIf(ptr(cfg.Port()), !cfg.ValueSet(PortKey)),
 			MaxConnections:          zeroIf(ptr(cfg.MaxConnections()), !cfg.ValueSet(MaxConnectionsKey)),
+			BackLog:                 zeroIf(ptr(cfg.MaxWaitConnections()), !cfg.ValueSet(MaxWaitConnectionsKey)),
 			ReadTimeoutMillis:       zeroIf(ptr(cfg.ReadTimeout()), !cfg.ValueSet(ReadTimeoutKey)),
 			WriteTimeoutMillis:      zeroIf(ptr(cfg.WriteTimeout()), !cfg.ValueSet(WriteTimeoutKey)),
 			TLSKey:                  zeroIf(ptr(cfg.TLSKey()), !cfg.ValueSet(TLSKeyKey)),
@@ -958,6 +960,8 @@ func (cfg YAMLConfig) ValueSet(value string) bool {
 		return cfg.ListenerConfig.WriteTimeoutMillis != nil
 	case MaxConnectionsKey:
 		return cfg.ListenerConfig.MaxConnections != nil
+	case MaxWaitConnectionsKey:
+		return cfg.ListenerConfig.BackLog != nil
 	case EventSchedulerKey:
 		return cfg.BehaviorConfig.EventSchedulerStatus != nil
 	}
diff --git a/integration-tests/bats/sql-server-config-file-generation.bats b/integration-tests/bats/sql-server-config-file-generation.bats
index 924a16541ed..ee3fa60235c 100644
--- a/integration-tests/bats/sql-server-config-file-generation.bats
+++ b/integration-tests/bats/sql-server-config-file-generation.bats
@@ -98,6 +98,7 @@ EOF
         --max-connections 77 \
         --timeout 7777777 \
         --allow-cleartext-passwords true \
+        --back-log 767 \
         --host 0.0.0.0
 
     run cat "$CONFIG_FILE_NAME"
@@ -108,6 +109,7 @@ EOF
     [[ "$output" =~ "read_timeout_millis: 7777777" ]] || false
     [[ "$output" =~ "write_timeout_millis: 7777777" ]] || false
     [[ "$output" =~ "allow_cleartext_passwords: true" ]] || false
+    [[ "$output" =~ "back_log: 767" ]] || false
 }
 
 @test "sql-server-config-file-generation: generated config file uses default values as placeholders for unset fields" {

From 66180b5623edc29761ed2e06f0ab0d276e82fb4e Mon Sep 17 00:00:00 2001
From: Neil Macneale IV <neil@dolthub.com>
Date: Thu, 20 Mar 2025 13:13:11 -0700
Subject: [PATCH 04/16] Reliable first test for max-conns and back-log

---
 integration-tests/bats/sql-server.bats | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/integration-tests/bats/sql-server.bats b/integration-tests/bats/sql-server.bats
index db48a231994..8f0e856fc3b 100644
--- a/integration-tests/bats/sql-server.bats
+++ b/integration-tests/bats/sql-server.bats
@@ -2115,3 +2115,29 @@ EOF
     [[ "$output" =~ "br3  | true" ]] || false
     [[ "$output" =~ "main | false" ]] || false
 }
+
+@test "sql-server: test --max-connections and --back-log flags" {
+    cd repo1
+    # 3 connections allowed, everything else immediate failure.
+    start_sql_server_with_args --max-connections 3 --back-log 0
+
+    # Start 3 long running connections.
+    set +e # errors expected.
+    pids=()
+    for i in {1..3}; do
+      dolt sql &
+      pids+=($!)
+    done
+
+    # Give the first 3 connections time to start/connect
+    sleep 5
+
+    run dolt sql -q "select(1);"
+    [ $status -ne 0 ]
+    [[ "$output" =~ "bad connection" ]] || false
+
+    # Kill all the running shells
+    for pid in "${pids[@]}"; do
+      kill -9 "$pid"
+    done
+}

From 11dcccd1cc4e3b9068d931bed4bc037160154274 Mon Sep 17 00:00:00 2001
From: Neil Macneale IV <neil@dolthub.com>
Date: Thu, 20 Mar 2025 13:53:44 -0700
Subject: [PATCH 05/16] Add more tests for max cons and back log

---
 integration-tests/bats/sql-server.bats | 93 ++++++++++++++++++++++++++
 1 file changed, 93 insertions(+)

diff --git a/integration-tests/bats/sql-server.bats b/integration-tests/bats/sql-server.bats
index 8f0e856fc3b..98dda65fa3e 100644
--- a/integration-tests/bats/sql-server.bats
+++ b/integration-tests/bats/sql-server.bats
@@ -2141,3 +2141,96 @@ EOF
       kill -9 "$pid"
     done
 }
+
+@test "sql-server: test --max-connections 3 flag" {
+    cd repo1
+
+    dolt sql -q "CREATE TABLE test_table (
+        id INT AUTO_INCREMENT PRIMARY KEY,
+        str VARCHAR(20)
+    );"
+    dolt commit -A -m "create test_table"
+
+    # 3 connections allowed, default back-log (50).
+    start_sql_server_with_args --max-connections 3
+
+    set +e # errors expected.
+
+    # Start 3 long running connections.
+    pids=()
+    for i in {1..3}; do
+      dolt sql &
+      pids+=($!)
+    done
+
+    sleep 1 # give all connections a chance to start
+
+    # These jobs will wait until there is a connection available. verify
+    # by ensuring the inserts complete.
+    dolt sql -q "insert into test_table (str) values ('test4223');" &
+    second_to_last_pid=$!
+    dolt sql -q "insert into test_table (str) values ('test9119');" &
+    last_pid=$!
+
+    sleep 1
+
+    # Now have two jobs waiting for a connection.
+
+    # Kill all the running shells
+    for pid in "${pids[@]}"; do
+      kill -9 "$pid"
+    done
+
+    wait "$second_to_last_pid"
+    wait "$last_pid"
+
+    run dolt sql -q "select * from test_table;"
+    [ $status -eq 0 ]
+    [[ "$output" =~ "test4223" ]] || false
+    [[ "$output" =~ "test9119" ]] || false
+}
+
+@test "sql-server: test --max-connections 3 and --back-log 1 flags" {
+    cd repo1
+
+    dolt sql -q "CREATE TABLE test_table (
+        id INT AUTO_INCREMENT PRIMARY KEY,
+        str VARCHAR(20)
+    );"
+    dolt commit -A -m "create test_table"
+
+    # 3 connections allowed, 1 connection in back-log.
+    start_sql_server_with_args --max-connections 3 --back-log 1
+
+    set +e # errors expected.
+    # Start 3 long running connections.
+    pids=()
+    for i in {1..3}; do
+      dolt sql &
+      pids+=($!)
+    done
+
+    # This job will wait until there is a connection available. verify
+    # by ensuring the insert completes.
+    dolt sql -q "insert into test_table (str) values ('test4223');" &
+    last_pid=$!
+
+    sleep 1 # give all connections a chance to start
+
+    # This operation should fail immediately.
+    run dolt sql -q "insert into test_table (str) values ('testxxxx');"
+    [ "$status" -ne 0 ]
+    [[ "$stderr" =~ "bad connection" ]] || false
+
+    # Kill all the running shells
+    for pid in "${pids[@]}"; do
+      kill -9 "$pid"
+    done
+
+    wait "$last_pid"
+
+    run dolt sql -q "select * from test_table;"
+    [ $status -eq 0 ]
+    [[ "$output" =~ "test4223" ]] || false
+    [[ ! "$output" =~ "testxxxx" ]] || false
+}

From 27ff3beaac71a98a3c794b25a2bc14f26b570685 Mon Sep 17 00:00:00 2001
From: Neil Macneale IV <neil@dolthub.com>
Date: Fri, 21 Mar 2025 11:21:10 -0700
Subject: [PATCH 06/16] Add max connections timeout

---
 .../commands/sqlserver/command_line_config.go | 22 ++++++++
 go/cmd/dolt/commands/sqlserver/server.go      |  1 +
 go/cmd/dolt/commands/sqlserver/sqlserver.go   |  4 ++
 .../doltcore/servercfg/serverconfig.go        | 52 +++++++++++--------
 .../doltcore/servercfg/yaml_config.go         | 29 ++++++++---
 .../sql-server-config-file-generation.bats    |  7 +++
 6 files changed, 86 insertions(+), 29 deletions(-)

diff --git a/go/cmd/dolt/commands/sqlserver/command_line_config.go b/go/cmd/dolt/commands/sqlserver/command_line_config.go
index 05eff0cf7f6..6716c20b37a 100755
--- a/go/cmd/dolt/commands/sqlserver/command_line_config.go
+++ b/go/cmd/dolt/commands/sqlserver/command_line_config.go
@@ -19,6 +19,7 @@ import (
 	"path/filepath"
 	"strconv"
 	"strings"
+	"time"
 
 	"github.com/dolthub/dolt/go/libraries/doltcore/servercfg"
 	"github.com/dolthub/dolt/go/libraries/utils/filesys"
@@ -43,6 +44,7 @@ type commandLineServerConfig struct {
 	doltTransactionCommit   bool
 	maxConnections          uint64
 	maxWaitConnections      uint32
+	maxWaitConnsTimeout     time.Duration
 	tlsKey                  string
 	tlsCert                 string
 	requireSecureTransport  bool
@@ -74,6 +76,7 @@ func DefaultCommandLineServerConfig() *commandLineServerConfig {
 		autoCommit:              servercfg.DefaultAutoCommit,
 		maxConnections:          servercfg.DefaultMaxConnections,
 		maxWaitConnections:      servercfg.DefaultMaxWaitConnections,
+		maxWaitConnsTimeout:     servercfg.DefaultMaxWaitConnectionsTimeout,
 		dataDir:                 servercfg.DefaultDataDir,
 		cfgDir:                  filepath.Join(servercfg.DefaultDataDir, servercfg.DefaultCfgDir),
 		privilegeFilePath:       filepath.Join(servercfg.DefaultDataDir, servercfg.DefaultCfgDir, servercfg.DefaultPrivilegeFilePath),
@@ -175,6 +178,14 @@ func NewCommandLineConfig(creds *cli.UserPassword, apr *argparser.ArgParseResult
 		config.withMaxWaitConnections(uint32(maxWaitConnections))
 	}
 
+	if maxWaitConnsTimeoutStr, ok := apr.GetValue(maxWaitConsTimeoutFlag); ok {
+		maxWaitConnsTimeout, err := time.ParseDuration(maxWaitConnsTimeoutStr)
+		if err != nil {
+			return nil, fmt.Errorf("invalid value for --max-wait-connections-timeout '%s'", maxWaitConnsTimeoutStr)
+		}
+		config.maxWaitConnsTimeout = maxWaitConnsTimeout
+	}
+
 	config.autoCommit = !apr.Contains(noAutoCommitFlag)
 	if apr.Contains(noAutoCommitFlag) {
 		config.valuesSet[servercfg.AutoCommitKey] = struct{}{}
@@ -270,6 +281,10 @@ func (cfg *commandLineServerConfig) MaxWaitConnections() uint32 {
 	return cfg.maxWaitConnections
 }
 
+func (cfg *commandLineServerConfig) MaxWaitConnectionsTimeout() time.Duration {
+	return cfg.maxWaitConnsTimeout
+}
+
 // TLSKey returns a path to the servers PEM-encoded private TLS key. "" if there is none.
 func (cfg *commandLineServerConfig) TLSKey() string {
 	return cfg.tlsKey
@@ -437,12 +452,19 @@ func (cfg *commandLineServerConfig) withMaxConnections(maxConnections uint64) *c
 	return cfg
 }
 
+// NM4 - I think we can drop this. Or take a str?
 func (cfg *commandLineServerConfig) withMaxWaitConnections(maxWaitConnections uint32) *commandLineServerConfig {
 	cfg.maxWaitConnections = maxWaitConnections
 	cfg.valuesSet[servercfg.MaxWaitConnectionsKey] = struct{}{}
 	return cfg
 }
 
+func (cfg *commandLineServerConfig) withMaxWaitConnectionsTimeout(maxWaitConnsTimeout time.Duration) *commandLineServerConfig {
+	cfg.maxWaitConnsTimeout = maxWaitConnsTimeout
+	cfg.valuesSet[servercfg.MaxWaitConnectionsTimeoutKey] = struct{}{}
+	return cfg
+}
+
 // withDataDir updates the path to a directory to use as the data dir.
 func (cfg *commandLineServerConfig) withDataDir(dataDir string) *commandLineServerConfig {
 	cfg.dataDir = dataDir
diff --git a/go/cmd/dolt/commands/sqlserver/server.go b/go/cmd/dolt/commands/sqlserver/server.go
index 366c4af12c3..05443d84dd3 100644
--- a/go/cmd/dolt/commands/sqlserver/server.go
+++ b/go/cmd/dolt/commands/sqlserver/server.go
@@ -1093,6 +1093,7 @@ func getConfigFromServerConfig(serverConfig servercfg.ServerConfig, plf server.P
 	serverConf.ConnWriteTimeout = writeTimeout
 	serverConf.MaxConnections = serverConfig.MaxConnections()
 	serverConf.MaxWaitConnections = serverConfig.MaxWaitConnections()
+	serverConf.MaxWaitConnectionsTimeout = serverConfig.MaxWaitConnectionsTimeout()
 	serverConf.TLSConfig = tlsConfig
 	serverConf.RequireSecureTransport = serverConfig.RequireSecureTransport()
 	serverConf.MaxLoggedQueryLen = serverConfig.MaxLoggedQueryLen()
diff --git a/go/cmd/dolt/commands/sqlserver/sqlserver.go b/go/cmd/dolt/commands/sqlserver/sqlserver.go
index 402e698e667..d1ddbcb6075 100644
--- a/go/cmd/dolt/commands/sqlserver/sqlserver.go
+++ b/go/cmd/dolt/commands/sqlserver/sqlserver.go
@@ -49,6 +49,7 @@ const (
 	queryParallelismFlag        = "query-parallelism"
 	maxConnectionsFlag          = "max-connections"
 	maxWaitConnectionsFlag      = "back-log"
+	maxWaitConsTimeoutFlag      = "max-connections-timeout"
 	allowCleartextPasswordsFlag = "allow-cleartext-passwords"
 	socketFlag                  = "socket"
 	remotesapiPortFlag          = "remotesapi-port"
@@ -110,6 +111,8 @@ SUPPORTED CONFIG FILE FIELDS:
 
 {{.EmphasisLeft}}listener.back_log{{.EmphasisRight}}: The number of simultaneous connections that the server will allow to block waiting for a connection before new connections result in immediate rejection. Default 50.
 
+{{.EmphasisLeft}}listener.max_wait_connections_timeout{{.EmphasisRight}}: The maximum amount of time that a connection will block waiting for a connection before being rejected.
+
 {{.EmphasisLeft}}listener.read_timeout_millis{{.EmphasisRight}}: The number of milliseconds that the server will wait for a read operation
 
 {{.EmphasisLeft}}listener.write_timeout_millis{{.EmphasisRight}}: The number of milliseconds that the server will wait for a write operation
@@ -183,6 +186,7 @@ func (cmd SqlServerCmd) ArgParserWithName(name string) *argparser.ArgParser {
 	ap.SupportsInt(queryParallelismFlag, "", "num-go-routines", "Deprecated, no effect in current versions of Dolt")
 	ap.SupportsInt(maxConnectionsFlag, "", "max-connections", fmt.Sprintf("Set the number of connections handled by the server. Defaults to `%d`.", serverConfig.MaxConnections()))
 	ap.SupportsInt(maxWaitConnectionsFlag, "", "back-log", fmt.Sprintf("Set the number of connections that can block waiting for a connection before new connections are rejected. Defaults to `%d`.", serverConfig.MaxWaitConnections()))
+	ap.SupportsString(maxWaitConsTimeoutFlag, "", "max-connections-timeout", fmt.Sprintf("Set the maximum duration that a connection will block waiting for a connection before being rejected. Defaults to `%v`.", serverConfig.MaxWaitConnectionsTimeout()))
 	ap.SupportsString(commands.PrivsFilePathFlag, "", "privilege file", "Path to a file to load and store users and grants. Defaults to `$doltcfg-dir/privileges.db`. Will be created as needed.")
 	ap.SupportsString(commands.BranchCtrlPathFlag, "", "branch control file", "Path to a file to load and store branch control permissions. Defaults to `$doltcfg-dir/branch_control.db`. Will be created as needed.")
 	ap.SupportsString(allowCleartextPasswordsFlag, "", "allow-cleartext-passwords", "Allows use of cleartext passwords. Defaults to false.")
diff --git a/go/libraries/doltcore/servercfg/serverconfig.go b/go/libraries/doltcore/servercfg/serverconfig.go
index d12fc16a7c0..02a67231ad8 100644
--- a/go/libraries/doltcore/servercfg/serverconfig.go
+++ b/go/libraries/doltcore/servercfg/serverconfig.go
@@ -22,6 +22,7 @@ import (
 	"path/filepath"
 	"runtime"
 	"strings"
+	"time"
 )
 
 var DefaultUnixSocketFilePath = DefaultMySQLUnixSocketFilePath
@@ -47,29 +48,30 @@ const (
 )
 
 const (
-	DefaultHost                    = "localhost"
-	DefaultPort                    = 3306
-	DefaultUser                    = "root"
-	DefaultPass                    = ""
-	DefaultTimeout                 = 8 * 60 * 60 * 1000 // 8 hours, same as MySQL
-	DefaultReadOnly                = false
-	DefaultLogLevel                = LogLevel_Info
-	DefaultLogFormat               = LogFormat_Text
-	DefaultAutoCommit              = true
-	DefaultAutoGCBehaviorEnable    = false
-	DefaultDoltTransactionCommit   = false
-	DefaultMaxConnections          = 1000
-	DefaultMaxWaitConnections      = 50
-	DefaultDataDir                 = "."
-	DefaultCfgDir                  = ".doltcfg"
-	DefaultPrivilegeFilePath       = "privileges.db"
-	DefaultBranchControlFilePath   = "branch_control.db"
-	DefaultMetricsHost             = ""
-	DefaultMetricsPort             = -1
-	DefaultAllowCleartextPasswords = false
-	DefaultMySQLUnixSocketFilePath = "/tmp/mysql.sock"
-	DefaultMaxLoggedQueryLen       = 0
-	DefaultEncodeLoggedQuery       = false
+	DefaultHost                      = "localhost"
+	DefaultPort                      = 3306
+	DefaultUser                      = "root"
+	DefaultPass                      = ""
+	DefaultTimeout                   = 8 * 60 * 60 * 1000 // 8 hours, same as MySQL
+	DefaultReadOnly                  = false
+	DefaultLogLevel                  = LogLevel_Info
+	DefaultLogFormat                 = LogFormat_Text
+	DefaultAutoCommit                = true
+	DefaultAutoGCBehaviorEnable      = false
+	DefaultDoltTransactionCommit     = false
+	DefaultMaxConnections            = 1000
+	DefaultMaxWaitConnections        = 50
+	DefaultMaxWaitConnectionsTimeout = 60 * time.Second
+	DefaultDataDir                   = "."
+	DefaultCfgDir                    = ".doltcfg"
+	DefaultPrivilegeFilePath         = "privileges.db"
+	DefaultBranchControlFilePath     = "branch_control.db"
+	DefaultMetricsHost               = ""
+	DefaultMetricsPort               = -1
+	DefaultAllowCleartextPasswords   = false
+	DefaultMySQLUnixSocketFilePath   = "/tmp/mysql.sock"
+	DefaultMaxLoggedQueryLen         = 0
+	DefaultEncodeLoggedQuery         = false
 )
 
 func ptr[T any](t T) *T {
@@ -163,6 +165,8 @@ type ServerConfig interface {
 	// MaxWaitConnections returns the maximum number of simultaneous connections that the server will allow to block waiting
 	// for a connection before new connections result in immediate rejection
 	MaxWaitConnections() uint32
+	// MaxWaitConnectionsTimeout returns the maximum amount of time that a connection will block waiting for a connection
+	MaxWaitConnectionsTimeout() time.Duration
 	// TLSKey returns a path to the servers PEM-encoded private TLS key. "" if there is none.
 	TLSKey() string
 	// TLSCert returns a path to the servers PEM-encoded TLS certificate chain. "" if there is none.
@@ -245,6 +249,7 @@ func defaultServerConfigYAML() *YAMLConfig {
 			PortNumber:              ptr(DefaultPort),
 			MaxConnections:          ptr(uint64(DefaultMaxConnections)),
 			BackLog:                 ptr(uint32(DefaultMaxWaitConnections)),
+			MaxConnectionsTimeoutMs: ptr(uint64(DefaultMaxWaitConnectionsTimeout.Milliseconds())),
 			ReadTimeoutMillis:       ptr(uint64(DefaultTimeout)),
 			WriteTimeoutMillis:      ptr(uint64(DefaultTimeout)),
 			AllowCleartextPasswords: ptr(DefaultAllowCleartextPasswords),
@@ -312,6 +317,7 @@ const (
 	CfgDirKey                       = "cfg_dir"
 	MaxConnectionsKey               = "max_connections"
 	MaxWaitConnectionsKey           = "back_log"
+	MaxWaitConnectionsTimeoutKey    = "max_connections_timeout"
 	TLSKeyKey                       = "tls_key"
 	TLSCertKey                      = "tls_cert"
 	RequireSecureTransportKey       = "require_secure_transport"
diff --git a/go/libraries/doltcore/servercfg/yaml_config.go b/go/libraries/doltcore/servercfg/yaml_config.go
index 664d68e04a4..2c537e59e4c 100644
--- a/go/libraries/doltcore/servercfg/yaml_config.go
+++ b/go/libraries/doltcore/servercfg/yaml_config.go
@@ -18,6 +18,7 @@ import (
 	"fmt"
 	"path/filepath"
 	"strings"
+	"time"
 	"unicode"
 	"unicode/utf8"
 
@@ -77,12 +78,13 @@ type UserYAMLConfig struct {
 
 // ListenerYAMLConfig contains information on the network connection that the server will open
 type ListenerYAMLConfig struct {
-	HostStr            *string `yaml:"host,omitempty"`
-	PortNumber         *int    `yaml:"port,omitempty"`
-	MaxConnections     *uint64 `yaml:"max_connections,omitempty"`
-	BackLog            *uint32 `yaml:"back_log,omitempty"`
-	ReadTimeoutMillis  *uint64 `yaml:"read_timeout_millis,omitempty"`
-	WriteTimeoutMillis *uint64 `yaml:"write_timeout_millis,omitempty"`
+	HostStr                 *string `yaml:"host,omitempty"`
+	PortNumber              *int    `yaml:"port,omitempty"`
+	MaxConnections          *uint64 `yaml:"max_connections,omitempty"`
+	BackLog                 *uint32 `yaml:"back_log,omitempty"`
+	MaxConnectionsTimeoutMs *uint64 `yaml:"max_connections_timeout_millis,omitempty"`
+	ReadTimeoutMillis       *uint64 `yaml:"read_timeout_millis,omitempty"`
+	WriteTimeoutMillis      *uint64 `yaml:"write_timeout_millis,omitempty"`
 	// TLSKey is a file system path to an unencrypted private TLS key in PEM format.
 	TLSKey *string `yaml:"tls_key,omitempty"`
 	// TLSCert is a file system path to a TLS certificate chain in PEM format.
@@ -199,6 +201,7 @@ func ServerConfigAsYAMLConfig(cfg ServerConfig) *YAMLConfig {
 			PortNumber:              ptr(cfg.Port()),
 			MaxConnections:          ptr(cfg.MaxConnections()),
 			BackLog:                 ptr(cfg.MaxWaitConnections()),
+			MaxConnectionsTimeoutMs: ptr(uint64(cfg.MaxWaitConnectionsTimeout().Milliseconds())),
 			ReadTimeoutMillis:       ptr(cfg.ReadTimeout()),
 			WriteTimeoutMillis:      ptr(cfg.WriteTimeout()),
 			TLSKey:                  nillableStrPtr(cfg.TLSKey()),
@@ -270,6 +273,7 @@ func ServerConfigSetValuesAsYAMLConfig(cfg ServerConfig) *YAMLConfig {
 			PortNumber:              zeroIf(ptr(cfg.Port()), !cfg.ValueSet(PortKey)),
 			MaxConnections:          zeroIf(ptr(cfg.MaxConnections()), !cfg.ValueSet(MaxConnectionsKey)),
 			BackLog:                 zeroIf(ptr(cfg.MaxWaitConnections()), !cfg.ValueSet(MaxWaitConnectionsKey)),
+			MaxConnectionsTimeoutMs: zeroIf(ptr(uint64(cfg.MaxWaitConnectionsTimeout().Milliseconds())), !cfg.ValueSet(MaxWaitConnectionsTimeoutKey)),
 			ReadTimeoutMillis:       zeroIf(ptr(cfg.ReadTimeout()), !cfg.ValueSet(ReadTimeoutKey)),
 			WriteTimeoutMillis:      zeroIf(ptr(cfg.WriteTimeout()), !cfg.ValueSet(WriteTimeoutKey)),
 			TLSKey:                  zeroIf(ptr(cfg.TLSKey()), !cfg.ValueSet(TLSKeyKey)),
@@ -493,6 +497,9 @@ func (cfg YAMLConfig) withDefaultsFilledIn() YAMLConfig {
 	if withDefaults.ListenerConfig.BackLog == nil {
 		withDefaults.ListenerConfig.BackLog = defaults.ListenerConfig.BackLog
 	}
+	if withDefaults.ListenerConfig.MaxConnectionsTimeoutMs == nil {
+		withDefaults.ListenerConfig.MaxConnectionsTimeoutMs = defaults.ListenerConfig.MaxConnectionsTimeoutMs
+	}
 	if withDefaults.ListenerConfig.ReadTimeoutMillis == nil {
 		withDefaults.ListenerConfig.ReadTimeoutMillis = defaults.ListenerConfig.ReadTimeoutMillis
 	}
@@ -673,6 +680,14 @@ func (cfg YAMLConfig) MaxWaitConnections() uint32 {
 	return *cfg.ListenerConfig.BackLog
 }
 
+func (cfg YAMLConfig) MaxWaitConnectionsTimeout() time.Duration {
+	if cfg.ListenerConfig.MaxConnectionsTimeoutMs == nil {
+		return DefaultMaxWaitConnectionsTimeout
+	}
+
+	return time.Duration(*cfg.ListenerConfig.MaxConnectionsTimeoutMs) * time.Millisecond
+}
+
 // DisableClientMultiStatements returns true if the server should run in a mode
 // where the CLIENT_MULTI_STATEMENTS option are ignored and every incoming
 // ComQuery packet is assumed to be a standalone query.
@@ -962,6 +977,8 @@ func (cfg YAMLConfig) ValueSet(value string) bool {
 		return cfg.ListenerConfig.MaxConnections != nil
 	case MaxWaitConnectionsKey:
 		return cfg.ListenerConfig.BackLog != nil
+	case MaxWaitConnectionsTimeoutKey:
+		return cfg.ListenerConfig.MaxConnectionsTimeoutMs != nil
 	case EventSchedulerKey:
 		return cfg.BehaviorConfig.EventSchedulerStatus != nil
 	}
diff --git a/integration-tests/bats/sql-server-config-file-generation.bats b/integration-tests/bats/sql-server-config-file-generation.bats
index ee3fa60235c..f5b908fed59 100644
--- a/integration-tests/bats/sql-server-config-file-generation.bats
+++ b/integration-tests/bats/sql-server-config-file-generation.bats
@@ -99,6 +99,7 @@ EOF
         --timeout 7777777 \
         --allow-cleartext-passwords true \
         --back-log 767 \
+        --max-connections-timeout 13s \
         --host 0.0.0.0
 
     run cat "$CONFIG_FILE_NAME"
@@ -110,6 +111,12 @@ EOF
     [[ "$output" =~ "write_timeout_millis: 7777777" ]] || false
     [[ "$output" =~ "allow_cleartext_passwords: true" ]] || false
     [[ "$output" =~ "back_log: 767" ]] || false
+
+    echo "--------------------------"
+    echo "$output"
+    echo "--------------------------"
+
+    [[ "$output" =~ "max_connections_timeout: 676" ]] || false
 }
 
 @test "sql-server-config-file-generation: generated config file uses default values as placeholders for unset fields" {

From ae18118f31273789ff9339235c4d59f24a673c18 Mon Sep 17 00:00:00 2001
From: Neil Macneale IV <neil@dolthub.com>
Date: Fri, 21 Mar 2025 13:19:12 -0700
Subject: [PATCH 07/16] Get max timeout for waiting connections all the way
 through

---
 go/cmd/dolt/commands/sqlserver/command_line_config.go    | 4 ++--
 .../bats/sql-server-config-file-generation.bats          | 9 ++-------
 2 files changed, 4 insertions(+), 9 deletions(-)

diff --git a/go/cmd/dolt/commands/sqlserver/command_line_config.go b/go/cmd/dolt/commands/sqlserver/command_line_config.go
index 6716c20b37a..458c451ea7b 100755
--- a/go/cmd/dolt/commands/sqlserver/command_line_config.go
+++ b/go/cmd/dolt/commands/sqlserver/command_line_config.go
@@ -181,9 +181,9 @@ func NewCommandLineConfig(creds *cli.UserPassword, apr *argparser.ArgParseResult
 	if maxWaitConnsTimeoutStr, ok := apr.GetValue(maxWaitConsTimeoutFlag); ok {
 		maxWaitConnsTimeout, err := time.ParseDuration(maxWaitConnsTimeoutStr)
 		if err != nil {
-			return nil, fmt.Errorf("invalid value for --max-wait-connections-timeout '%s'", maxWaitConnsTimeoutStr)
+			return nil, fmt.Errorf("invalid duration value for --max-wait-connections-timeout '%s'", maxWaitConnsTimeoutStr)
 		}
-		config.maxWaitConnsTimeout = maxWaitConnsTimeout
+		config.withMaxWaitConnectionsTimeout(maxWaitConnsTimeout)
 	}
 
 	config.autoCommit = !apr.Contains(noAutoCommitFlag)
diff --git a/integration-tests/bats/sql-server-config-file-generation.bats b/integration-tests/bats/sql-server-config-file-generation.bats
index f5b908fed59..f4e1837acd3 100644
--- a/integration-tests/bats/sql-server-config-file-generation.bats
+++ b/integration-tests/bats/sql-server-config-file-generation.bats
@@ -99,7 +99,7 @@ EOF
         --timeout 7777777 \
         --allow-cleartext-passwords true \
         --back-log 767 \
-        --max-connections-timeout 13s \
+        --max-connections-timeout 6m13s \
         --host 0.0.0.0
 
     run cat "$CONFIG_FILE_NAME"
@@ -111,12 +111,7 @@ EOF
     [[ "$output" =~ "write_timeout_millis: 7777777" ]] || false
     [[ "$output" =~ "allow_cleartext_passwords: true" ]] || false
     [[ "$output" =~ "back_log: 767" ]] || false
-
-    echo "--------------------------"
-    echo "$output"
-    echo "--------------------------"
-
-    [[ "$output" =~ "max_connections_timeout: 676" ]] || false
+    [[ "$output" =~ "max_connections_timeout_millis: 373000" ]] || false
 }
 
 @test "sql-server-config-file-generation: generated config file uses default values as placeholders for unset fields" {

From aacde670b0983b72f83e54deb8ba3088ebfd3b48 Mon Sep 17 00:00:00 2001
From: Neil Macneale IV <neil@dolthub.com>
Date: Mon, 24 Mar 2025 10:20:58 -0700
Subject: [PATCH 08/16] Test the --max-connections-timeout has an effect

---
 integration-tests/bats/sql-server.bats | 30 ++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/integration-tests/bats/sql-server.bats b/integration-tests/bats/sql-server.bats
index 98dda65fa3e..35a248502ea 100644
--- a/integration-tests/bats/sql-server.bats
+++ b/integration-tests/bats/sql-server.bats
@@ -2234,3 +2234,33 @@ EOF
     [[ "$output" =~ "test4223" ]] || false
     [[ ! "$output" =~ "testxxxx" ]] || false
 }
+
+# bats test_tags=no_lambda
+@test "sql-server: test --max-connections-timeout 15s and --max-connections 3 flags" {
+    cd repo1
+
+    # Default is 60s, but I don't want to extend the test time for this.
+    start_sql_server_with_args --max-connections-timeout=15s --max-connections=3
+
+    pids=()
+    for i in {1..3}; do
+      dolt sql &
+      pids+=($!)
+    done
+
+    # Attempt to connect with a fourth connection using mysql client because dolt sql has
+    # 9 retries which we don't have the patience to wait for.
+    start_time=$(date +%s)
+    run mysql -h 127.0.0.1 -P 3306 -u root -e "SELECT 1;"
+    end_time=$(date +%s)
+
+    elapsed_time=$((end_time - start_time))
+    [[ $elapsed_time -lt 17 ]] || false
+    [[ $elapsed_time -gt 13 ]] || false
+    [ $status -ne 0 ]
+    [[ "$output" =~ "Lost connection to MySQL server at 'reading initial communication packet'" ]] || false
+
+    for pid in "${pids[@]}"; do
+      kill -9 "$pid"
+    done
+}

From 44313be0d86d4060eb1cffa6453f867b66e79613 Mon Sep 17 00:00:00 2001
From: Neil Macneale IV <neil@dolthub.com>
Date: Mon, 24 Mar 2025 10:53:09 -0700
Subject: [PATCH 09/16] Cleanup

---
 go/cmd/dolt/commands/sqlserver/command_line_config.go | 1 -
 1 file changed, 1 deletion(-)

diff --git a/go/cmd/dolt/commands/sqlserver/command_line_config.go b/go/cmd/dolt/commands/sqlserver/command_line_config.go
index 458c451ea7b..9ad8cf86f27 100755
--- a/go/cmd/dolt/commands/sqlserver/command_line_config.go
+++ b/go/cmd/dolt/commands/sqlserver/command_line_config.go
@@ -452,7 +452,6 @@ func (cfg *commandLineServerConfig) withMaxConnections(maxConnections uint64) *c
 	return cfg
 }
 
-// NM4 - I think we can drop this. Or take a str?
 func (cfg *commandLineServerConfig) withMaxWaitConnections(maxWaitConnections uint32) *commandLineServerConfig {
 	cfg.maxWaitConnections = maxWaitConnections
 	cfg.valuesSet[servercfg.MaxWaitConnectionsKey] = struct{}{}

From cd407bcbc8db774195035e4bd10fe203a2986698 Mon Sep 17 00:00:00 2001
From: Neil Macneale IV <neil@dolthub.com>
Date: Mon, 24 Mar 2025 15:25:28 -0700
Subject: [PATCH 10/16] Update missed go test

---
 go/cmd/dolt/commands/sqlserver/server_test.go | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/go/cmd/dolt/commands/sqlserver/server_test.go b/go/cmd/dolt/commands/sqlserver/server_test.go
index 9a1d7ce9216..1d532a92d15 100644
--- a/go/cmd/dolt/commands/sqlserver/server_test.go
+++ b/go/cmd/dolt/commands/sqlserver/server_test.go
@@ -595,6 +595,8 @@ listener:
   # host: localhost
   # port: 3306
   # max_connections: 1000
+  # back_log: 50
+  # max_connections_timeout_millis: 60000
   read_timeout_millis: 11000
   write_timeout_millis: 11000
   # tls_key: key.pem

From ff8320fce5099121331b95c19cf7cefd355bae69 Mon Sep 17 00:00:00 2001
From: Neil Macneale IV <neil@dolthub.com>
Date: Mon, 24 Mar 2025 15:39:33 -0700
Subject: [PATCH 11/16] More test goodness

---
 .../doltcore/servercfg/testdata/minver_validation.txt         | 4 +++-
 go/libraries/doltcore/servercfg/yaml_config_test.go           | 2 ++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/go/libraries/doltcore/servercfg/testdata/minver_validation.txt b/go/libraries/doltcore/servercfg/testdata/minver_validation.txt
index cbb390420a9..aac26ffbf93 100644
--- a/go/libraries/doltcore/servercfg/testdata/minver_validation.txt
+++ b/go/libraries/doltcore/servercfg/testdata/minver_validation.txt
@@ -21,6 +21,8 @@ ListenerConfig servercfg.ListenerYAMLConfig 0.0.0 listener,omitempty
 -HostStr *string 0.0.0 host,omitempty
 -PortNumber *int 0.0.0 port,omitempty
 -MaxConnections *uint64 0.0.0 max_connections,omitempty
+-BackLog *uint32 0.0.0 back_log,omitempty
+-MaxConnectionsTimeoutMs *uint64 0.0.0 max_connections_timeout_millis,omitempty
 -ReadTimeoutMillis *uint64 0.0.0 read_timeout_millis,omitempty
 -WriteTimeoutMillis *uint64 0.0.0 write_timeout_millis,omitempty
 -TLSKey *string 0.0.0 tls_key,omitempty
@@ -64,4 +66,4 @@ ClusterCfg *servercfg.ClusterYAMLConfig 0.0.0 cluster,omitempty
 --TLSCert_ string 0.0.0 tls_cert
 --TLSCA_ string 0.0.0 tls_ca
 --URLMatches []string 0.0.0 server_name_urls
---DNSMatches []string 0.0.0 server_name_dns
\ No newline at end of file
+--DNSMatches []string 0.0.0 server_name_dns
diff --git a/go/libraries/doltcore/servercfg/yaml_config_test.go b/go/libraries/doltcore/servercfg/yaml_config_test.go
index 8214e8f230d..bd218de95ec 100644
--- a/go/libraries/doltcore/servercfg/yaml_config_test.go
+++ b/go/libraries/doltcore/servercfg/yaml_config_test.go
@@ -41,6 +41,8 @@ listener:
     host: localhost
     port: 3306
     max_connections: 1000
+    back_log: 50
+    max_connections_timeout_millis: 60000
     read_timeout_millis: 28800000
     write_timeout_millis: 28800000
     

From 24c4e7ca204653e313c32912965607654cae7a9d Mon Sep 17 00:00:00 2001
From: Neil Macneale IV <neil@dolthub.com>
Date: Mon, 24 Mar 2025 17:47:22 -0700
Subject: [PATCH 12/16] Make the last timeout test more reliable

---
 integration-tests/bats/sql-server.bats | 33 +++++++++++++++++++-------
 1 file changed, 24 insertions(+), 9 deletions(-)

diff --git a/integration-tests/bats/sql-server.bats b/integration-tests/bats/sql-server.bats
index 35a248502ea..61aec0fdd20 100644
--- a/integration-tests/bats/sql-server.bats
+++ b/integration-tests/bats/sql-server.bats
@@ -2237,30 +2237,45 @@ EOF
 
 # bats test_tags=no_lambda
 @test "sql-server: test --max-connections-timeout 15s and --max-connections 3 flags" {
+    skiponwindows "mysql client required"
+
     cd repo1
 
+    export PORT=$( definePORT )
+
     # Default is 60s, but I don't want to extend the test time for this.
-    start_sql_server_with_args --max-connections-timeout=15s --max-connections=3
+    start_sql_server_with_args_no_port --max-connections-timeout=10s --max-connections=3 --back-log=10 --port=$PORT
 
+    # For this test we use the mysql client, which doesn't retry connections, but also seems to exit early
+    # if we don't give it a query. So we use a sleep to hang the three connections. These will be killed, so
+    # they won't run the full 30s.
     pids=()
     for i in {1..3}; do
-      dolt sql &
+      mysql -h 127.0.0.1 -P $PORT -u root -D repo1 -e "select sleep(30)" &
       pids+=($!)
     done
 
-    # Attempt to connect with a fourth connection using mysql client because dolt sql has
-    # 9 retries which we don't have the patience to wait for.
+    sleep 3
+
+    # Attempt to connect with a fourth connection - should fail after 10s. `run` caused a lot of variance in the test
+    # time, so we avoid using it here.
     start_time=$(date +%s)
-    run mysql -h 127.0.0.1 -P 3306 -u root -e "SELECT 1;"
+    set +e
+    mysql -h 127.0.0.1 -P $PORT -u root > $BATS_TMPDIR/mysql.out
+    status=$?
     end_time=$(date +%s)
+    [ $status -ne 0 ]
 
+    # There is a high amount of variance in the time it takes to fail, so we just check that it is within a range
+    # with a pretty high upper bound.
     elapsed_time=$((end_time - start_time))
-    [[ $elapsed_time -lt 17 ]] || false
-    [[ $elapsed_time -gt 13 ]] || false
-    [ $status -ne 0 ]
+    [[ $elapsed_time -lt 15 ]] || false
+    [[ $elapsed_time -gt 9 ]] || false
+
+    run cat $BATS_TMPDIR/mysql.out
     [[ "$output" =~ "Lost connection to MySQL server at 'reading initial communication packet'" ]] || false
 
     for pid in "${pids[@]}"; do
-      kill -9 "$pid"
+      kill "$pid" 2>/dev/null
     done
 }

From 9b35e9b879ad9834057898b22d4bf67a1464f194 Mon Sep 17 00:00:00 2001
From: Aaron Son <aaron@dolthub.com>
Date: Tue, 25 Mar 2025 15:02:16 -0700
Subject: [PATCH 13/16] go: binlogreplication: binlog_primary_test.go: Fix up
 for timestamp rounding instead of truncation.

---
 .../doltcore/sqle/binlogreplication/binlog_primary_test.go  | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/go/libraries/doltcore/sqle/binlogreplication/binlog_primary_test.go b/go/libraries/doltcore/sqle/binlogreplication/binlog_primary_test.go
index 799c7bff41f..313decd34f0 100644
--- a/go/libraries/doltcore/sqle/binlogreplication/binlog_primary_test.go
+++ b/go/libraries/doltcore/sqle/binlogreplication/binlog_primary_test.go
@@ -171,9 +171,9 @@ func TestBinlogPrimary(t *testing.T) {
 		{"1", "42", nil, nil, "123", "123", "123", "123", "200", "200", "200", "200", "200",
 			float32(1.0101), float64(2.02030405060708),
 			"1981", "1981-02-16", "-123:45:30.123456",
-			"1981-02-16 06:01:02", "1981-02-16 06:01:02.2", "1981-02-16 06:01:02.23", "1981-02-16 06:01:02.234",
-			"1981-02-16 06:01:02.2345", "1981-02-16 06:01:02.23456", "1981-02-16 06:01:02.234567",
-			"2024-04-08 10:30:42", "2024-04-08 10:30:42.8", "2024-04-08 10:30:42.87", "2024-04-08 10:30:42.876",
+			"1981-02-16 06:01:02", "1981-02-16 06:01:02.2", "1981-02-16 06:01:02.23", "1981-02-16 06:01:02.235",
+			"1981-02-16 06:01:02.2346", "1981-02-16 06:01:02.23457", "1981-02-16 06:01:02.234567",
+			"2024-04-08 10:30:43", "2024-04-08 10:30:42.9", "2024-04-08 10:30:42.88", "2024-04-08 10:30:42.877",
 			"2024-04-08 10:30:42.8765", "2024-04-08 10:30:42.87654", "2024-04-08 10:30:42.876543",
 			"\x01\x03",
 			"green", "pants,tie,belt",

From 9f47fa929730dff5d8e1e1f86a2b18ffa48d184c Mon Sep 17 00:00:00 2001
From: Aaron Son <aaron@dolthub.com>
Date: Tue, 25 Mar 2025 15:24:26 -0700
Subject: [PATCH 14/16] go/store/datas/commit_meta.go: Round the CommitMeta
 Timestamp when we format it for presentation. Better matches the behavior of
 these timestamps on the wire.

---
 go/store/datas/commit_meta.go | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/go/store/datas/commit_meta.go b/go/store/datas/commit_meta.go
index d0839dd8f08..7928929e335 100644
--- a/go/store/datas/commit_meta.go
+++ b/go/store/datas/commit_meta.go
@@ -205,8 +205,10 @@ func (cm *CommitMeta) Time() time.Time {
 
 // FormatTS takes the internal timestamp and turns it into a human readable string in the time.RubyDate format
 // which looks like: "Mon Jan 02 15:04:05 -0700 2006"
+//
+// We round this to the nearest second, which is what MySQL timestamp does by default.
 func (cm *CommitMeta) FormatTS() string {
-	return cm.Time().In(CommitLoc).Format(time.RubyDate)
+	return cm.Time().In(CommitLoc).Round(time.Second).Format(time.RubyDate)
 }
 
 // String returns the human readable string representation of the commit data

From 9e0e0a2f3f2d0861214d4eab5287b4e2225b9e54 Mon Sep 17 00:00:00 2001
From: Neil Macneale IV <neil@dolthub.com>
Date: Tue, 25 Mar 2025 15:33:42 -0700
Subject: [PATCH 15/16] PR Feedback

---
 go/libraries/doltcore/servercfg/yaml_config.go | 4 ++--
 integration-tests/bats/sql-server.bats         | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/go/libraries/doltcore/servercfg/yaml_config.go b/go/libraries/doltcore/servercfg/yaml_config.go
index 2c537e59e4c..3a8bf1d36f1 100644
--- a/go/libraries/doltcore/servercfg/yaml_config.go
+++ b/go/libraries/doltcore/servercfg/yaml_config.go
@@ -81,8 +81,8 @@ type ListenerYAMLConfig struct {
 	HostStr                 *string `yaml:"host,omitempty"`
 	PortNumber              *int    `yaml:"port,omitempty"`
 	MaxConnections          *uint64 `yaml:"max_connections,omitempty"`
-	BackLog                 *uint32 `yaml:"back_log,omitempty"`
-	MaxConnectionsTimeoutMs *uint64 `yaml:"max_connections_timeout_millis,omitempty"`
+	BackLog                 *uint32 `yaml:"back_log,omitempty" minver:"1.50.10"`
+	MaxConnectionsTimeoutMs *uint64 `yaml:"max_connections_timeout_millis,omitempty" minver:"1.50.10"`
 	ReadTimeoutMillis       *uint64 `yaml:"read_timeout_millis,omitempty"`
 	WriteTimeoutMillis      *uint64 `yaml:"write_timeout_millis,omitempty"`
 	// TLSKey is a file system path to an unencrypted private TLS key in PEM format.
diff --git a/integration-tests/bats/sql-server.bats b/integration-tests/bats/sql-server.bats
index 61aec0fdd20..59a8da0c267 100644
--- a/integration-tests/bats/sql-server.bats
+++ b/integration-tests/bats/sql-server.bats
@@ -2236,7 +2236,7 @@ EOF
 }
 
 # bats test_tags=no_lambda
-@test "sql-server: test --max-connections-timeout 15s and --max-connections 3 flags" {
+@test "sql-server: test --max-connections-timeout 10s and --max-connections 3 flags" {
     skiponwindows "mysql client required"
 
     cd repo1
@@ -2244,7 +2244,7 @@ EOF
     export PORT=$( definePORT )
 
     # Default is 60s, but I don't want to extend the test time for this.
-    start_sql_server_with_args_no_port --max-connections-timeout=10s --max-connections=3 --back-log=10 --port=$PORT
+    start_sql_server_with_args_no_port --max-connections-timeout=10s --max-connections=3 --port=$PORT
 
     # For this test we use the mysql client, which doesn't retry connections, but also seems to exit early
     # if we don't give it a query. So we use a sleep to hang the three connections. These will be killed, so

From 8a73e44231debe2b99af505abbef9078e81078f9 Mon Sep 17 00:00:00 2001
From: Neil Macneale IV <neil@dolthub.com>
Date: Tue, 25 Mar 2025 15:42:37 -0700
Subject: [PATCH 16/16] More test fixes

---
 .../doltcore/servercfg/testdata/minver_validation.txt         | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/go/libraries/doltcore/servercfg/testdata/minver_validation.txt b/go/libraries/doltcore/servercfg/testdata/minver_validation.txt
index aac26ffbf93..8bd6035586e 100644
--- a/go/libraries/doltcore/servercfg/testdata/minver_validation.txt
+++ b/go/libraries/doltcore/servercfg/testdata/minver_validation.txt
@@ -21,8 +21,8 @@ ListenerConfig servercfg.ListenerYAMLConfig 0.0.0 listener,omitempty
 -HostStr *string 0.0.0 host,omitempty
 -PortNumber *int 0.0.0 port,omitempty
 -MaxConnections *uint64 0.0.0 max_connections,omitempty
--BackLog *uint32 0.0.0 back_log,omitempty
--MaxConnectionsTimeoutMs *uint64 0.0.0 max_connections_timeout_millis,omitempty
+-BackLog *uint32 1.50.10 back_log,omitempty
+-MaxConnectionsTimeoutMs *uint64 1.50.10 max_connections_timeout_millis,omitempty
 -ReadTimeoutMillis *uint64 0.0.0 read_timeout_millis,omitempty
 -WriteTimeoutMillis *uint64 0.0.0 write_timeout_millis,omitempty
 -TLSKey *string 0.0.0 tls_key,omitempty