From 3f43400e3ab5fd58eb94f64dc433e670f1a5c3ef Mon Sep 17 00:00:00 2001
From: wangzihuacool <wangzihuacool@163.com>
Date: Thu, 20 Oct 2022 13:34:31 +0000
Subject: [PATCH 01/28] add-rocksdb-as-transactional-engine

---
 go/base/context.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/go/base/context.go b/go/base/context.go
index f3fe712..bdfe156 100644
--- a/go/base/context.go
+++ b/go/base/context.go
@@ -427,6 +427,10 @@ func (this *MigrationContext) IsTransactionalTable() bool {
 		{
 			return true
 		}
+	case "rocksdb":
+		{
+			return true
+		}
 	}
 	return false
 }

From 2793e2b6b317465e06a9e9a99f4af52ebd64a304 Mon Sep 17 00:00:00 2001
From: Hasan Mshawrab <63023909+hasanMshawrab@users.noreply.github.com>
Date: Wed, 26 Oct 2022 10:28:27 +0300
Subject: [PATCH 02/28] Fix: Change table name

table name is 'tbl' not 'tble'
---
 doc/shared-key.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/shared-key.md b/doc/shared-key.md
index c7f24cc..3dfa39b 100644
--- a/doc/shared-key.md
+++ b/doc/shared-key.md
@@ -29,7 +29,7 @@ CREATE TABLE tbl (
 
 (This is also the definition of the _ghost_ table, except that that table would be called `_tbl_gho`). 
 
-In this migration, the _before_ and _after_ versions contain the same unique not-null key (the PRIMARY KEY). To run this migration, `gh-ost` would iterate through the `tbl` table using the primary key, copy rows from `tbl` to the _ghost_ table `_tbl_gho` in primary key order, while also applying the binlog event writes from `tble` onto `_tbl_gho`.
+In this migration, the _before_ and _after_ versions contain the same unique not-null key (the PRIMARY KEY). To run this migration, `gh-ost` would iterate through the `tbl` table using the primary key, copy rows from `tbl` to the _ghost_ table `_tbl_gho` in primary key order, while also applying the binlog event writes from `tbl` onto `_tbl_gho`.
 
 The applying of the binlog events is what requires the shared unique key. For example, an `UPDATE` statement to `tbl` translates to a `REPLACE` statement which `gh-ost` applies to `_tbl_gho`. A `REPLACE` statement expects to insert or replace an existing row based on its row's values and the table's unique key constraints. In particular, if inserting that row would result in a unique key violation (e.g., a row with that primary key already exists), it would _replace_ that existing row with the new values.
 

From 515aa72d3d9b756e454b0168b4e57bc599b45e36 Mon Sep 17 00:00:00 2001
From: Nicholas Calugar <nicholas.calugar@gusto.com>
Date: Thu, 27 Oct 2022 11:42:12 -0700
Subject: [PATCH 03/28] Print status to migration context logger

---
 go/logic/migrator.go | 1 +
 1 file changed, 1 insertion(+)

diff --git a/go/logic/migrator.go b/go/logic/migrator.go
index b443d69..22b7c9f 100644
--- a/go/logic/migrator.go
+++ b/go/logic/migrator.go
@@ -1036,6 +1036,7 @@ func (this *Migrator) printStatus(rule PrintStatusRule, writers ...io.Writer) {
 	)
 	w := io.MultiWriter(writers...)
 	fmt.Fprintln(w, status)
+	this.migrationContext.Log.Infof(status)
 
 	hooksStatusIntervalSec := this.migrationContext.HooksStatusIntervalSec
 	if hooksStatusIntervalSec > 0 && elapsedSeconds%hooksStatusIntervalSec == 0 {

From 1be6a4c0823d3ed22f58ff1ff77bc34eff7797a0 Mon Sep 17 00:00:00 2001
From: Morgan Tocker <mtocker@squareup.com>
Date: Wed, 9 Nov 2022 20:11:49 -0700
Subject: [PATCH 04/28] Attempt instant DDL if supported

---
 go/base/context.go    |  1 +
 go/cmd/gh-ost/main.go |  2 ++
 go/logic/applier.go   | 48 +++++++++++++++++++++++++++++++++++++++++++
 go/logic/migrator.go  | 25 ++++++++++++++++++++++
 4 files changed, 76 insertions(+)

diff --git a/go/base/context.go b/go/base/context.go
index 270b7a0..6032a93 100644
--- a/go/base/context.go
+++ b/go/base/context.go
@@ -101,6 +101,7 @@ type MigrationContext struct {
 	AliyunRDS                bool
 	GoogleCloudPlatform      bool
 	AzureMySQL               bool
+	AttemptInstantDDL        bool
 
 	config            ContextConfig
 	configMutex       *sync.Mutex
diff --git a/go/cmd/gh-ost/main.go b/go/cmd/gh-ost/main.go
index b99e70b..660c492 100644
--- a/go/cmd/gh-ost/main.go
+++ b/go/cmd/gh-ost/main.go
@@ -67,6 +67,8 @@ func main() {
 	flag.StringVar(&migrationContext.DatabaseName, "database", "", "database name (mandatory)")
 	flag.StringVar(&migrationContext.OriginalTableName, "table", "", "table name (mandatory)")
 	flag.StringVar(&migrationContext.AlterStatement, "alter", "", "alter statement (mandatory)")
+	flag.BoolVar(&migrationContext.AttemptInstantDDL, "attempt-instant-ddl", true, "Attempt to use instant DDL for this migration first.")
+
 	flag.BoolVar(&migrationContext.CountTableRows, "exact-rowcount", false, "actually count table rows as opposed to estimate them (results in more accurate progress estimation)")
 	flag.BoolVar(&migrationContext.ConcurrentCountTableRows, "concurrent-rowcount", true, "(with --exact-rowcount), when true (default): count rows after row-copy begins, concurrently, and adjust row estimate later on; when false: first count rows, then start row copy")
 	flag.BoolVar(&migrationContext.AllowedRunningOnMaster, "allow-on-master", false, "allow this migration to run directly on master. Preferably it would run on a replica")
diff --git a/go/logic/applier.go b/go/logic/applier.go
index 50fd9bd..b9313a3 100644
--- a/go/logic/applier.go
+++ b/go/logic/applier.go
@@ -188,6 +188,54 @@ func (this *Applier) ValidateOrDropExistingTables() error {
 	return nil
 }
 
+// AttemptInstantDDL attempts to use instant DDL (from MySQL 8.0, and earlier in Aurora and some others.)
+// to apply the ALTER statement immediately. If it errors, the original
+// gh-ost algorithm can be used. However, if it's successful -- a lot
+// of time can potentially be saved. Instant operations include:
+// - Adding a column
+// - Dropping a column
+// - Dropping an index
+// - Extending a varchar column
+// It is safer to attempt the change than try and parse the DDL, since
+// there might be specifics about the table which make it not possible to apply instantly.
+func (this *Applier) AttemptInstantDDL() error {
+
+	query := fmt.Sprintf(`ALTER /* gh-ost */ TABLE %s.%s %s, ALGORITHM=INSTANT`,
+		sql.EscapeName(this.migrationContext.DatabaseName),
+		sql.EscapeName(this.migrationContext.OriginalTableName),
+		this.migrationContext.AlterStatementOptions,
+	)
+	this.migrationContext.Log.Infof("INSTANT DDL Query is: %s", query)
+
+	err := func() error {
+		tx, err := this.db.Begin()
+		if err != nil {
+			return err
+		}
+		defer tx.Rollback()
+
+		sessionQuery := fmt.Sprintf(`SET SESSION time_zone = '%s'`, this.migrationContext.ApplierTimeZone)
+		sessionQuery = fmt.Sprintf("%s, %s", sessionQuery, this.generateSqlModeQuery())
+
+		if _, err := tx.Exec(sessionQuery); err != nil {
+			return err
+		}
+		if _, err := tx.Exec(query); err != nil {
+			this.migrationContext.Log.Infof("INSTANT DDL failed: %s", err)
+			return err
+		}
+		if err := tx.Commit(); err != nil {
+			// Neither SET SESSION nor ALTER are really transactional, so strictly speaking
+			// there's no need to commit; but let's do this the legit way anyway.
+			return err
+		}
+		return nil
+	}()
+
+	return err
+
+}
+
 // CreateGhostTable creates the ghost table on the applier host
 func (this *Applier) CreateGhostTable() error {
 	query := fmt.Sprintf(`create /* gh-ost */ table %s.%s like %s.%s`,
diff --git a/go/logic/migrator.go b/go/logic/migrator.go
index b443d69..40415d0 100644
--- a/go/logic/migrator.go
+++ b/go/logic/migrator.go
@@ -351,12 +351,26 @@ func (this *Migrator) Migrate() (err error) {
 	if err := this.initiateInspector(); err != nil {
 		return err
 	}
+	// In MySQL 8.0 (and possibly earlier) some DDL statements can be applied instantly.
+	// As just a metadata change. We can't detect this unless we attempt the statement
+	// (i.e. there is no explain for DDL).
+	if this.migrationContext.AttemptInstantDDL {
+		this.migrationContext.Log.Infof("Attempting to execute ALTER TABLE as INSTANT DDL")
+		if err := this.attemptInstantDDL(); err == nil {
+			this.migrationContext.Log.Infof("Success! Table %s.%s migrated instantly", sql.EscapeName(this.migrationContext.DatabaseName), sql.EscapeName(this.migrationContext.OriginalTableName))
+			return nil
+		} else {
+			this.migrationContext.Log.Infof("INSTANT DDL failed, will proceed with original algorithm: %s", err)
+		}
+	}
+
 	if err := this.initiateStreaming(); err != nil {
 		return err
 	}
 	if err := this.initiateApplier(); err != nil {
 		return err
 	}
+
 	if err := this.createFlagFiles(); err != nil {
 		return err
 	}
@@ -734,6 +748,17 @@ func (this *Migrator) initiateServer() (err error) {
 	return nil
 }
 
+// attemptInstantDDL tries to apply the DDL statement directly to the table
+// using a ALGORITHM=INSTANT assertion. If this fails, it will return an error,
+// in which case the original algorithm should be used.
+func (this *Migrator) attemptInstantDDL() (err error) {
+	this.applier = NewApplier(this.migrationContext)
+	if err := this.applier.InitDBConnections(); err != nil {
+		return err
+	}
+	return this.applier.AttemptInstantDDL()
+}
+
 // initiateInspector connects, validates and inspects the "inspector" server.
 // The "inspector" server is typically a replica; it is where we issue some
 // queries such as:

From 05f32ebf297456ee759ced15aaa124acb6e7d207 Mon Sep 17 00:00:00 2001
From: Morgan Tocker <mtocker@squareup.com>
Date: Thu, 10 Nov 2022 09:30:13 -0700
Subject: [PATCH 05/28] minor cleanup

---
 go/logic/applier.go  | 32 +++-----------------------------
 go/logic/migrator.go |  1 -
 2 files changed, 3 insertions(+), 30 deletions(-)

diff --git a/go/logic/applier.go b/go/logic/applier.go
index b9313a3..abda2b0 100644
--- a/go/logic/applier.go
+++ b/go/logic/applier.go
@@ -199,41 +199,15 @@ func (this *Applier) ValidateOrDropExistingTables() error {
 // It is safer to attempt the change than try and parse the DDL, since
 // there might be specifics about the table which make it not possible to apply instantly.
 func (this *Applier) AttemptInstantDDL() error {
-
 	query := fmt.Sprintf(`ALTER /* gh-ost */ TABLE %s.%s %s, ALGORITHM=INSTANT`,
 		sql.EscapeName(this.migrationContext.DatabaseName),
 		sql.EscapeName(this.migrationContext.OriginalTableName),
 		this.migrationContext.AlterStatementOptions,
 	)
-	this.migrationContext.Log.Infof("INSTANT DDL Query is: %s", query)
-
-	err := func() error {
-		tx, err := this.db.Begin()
-		if err != nil {
-			return err
-		}
-		defer tx.Rollback()
-
-		sessionQuery := fmt.Sprintf(`SET SESSION time_zone = '%s'`, this.migrationContext.ApplierTimeZone)
-		sessionQuery = fmt.Sprintf("%s, %s", sessionQuery, this.generateSqlModeQuery())
-
-		if _, err := tx.Exec(sessionQuery); err != nil {
-			return err
-		}
-		if _, err := tx.Exec(query); err != nil {
-			this.migrationContext.Log.Infof("INSTANT DDL failed: %s", err)
-			return err
-		}
-		if err := tx.Commit(); err != nil {
-			// Neither SET SESSION nor ALTER are really transactional, so strictly speaking
-			// there's no need to commit; but let's do this the legit way anyway.
-			return err
-		}
-		return nil
-	}()
-
+	this.migrationContext.Log.Infof("INSTANT DDL query is: %s", query)
+	// We don't need a trx, because for instant DDL the SQL mode doesn't matter.
+	_, err := this.db.Exec(query)
 	return err
-
 }
 
 // CreateGhostTable creates the ghost table on the applier host
diff --git a/go/logic/migrator.go b/go/logic/migrator.go
index 40415d0..25989f8 100644
--- a/go/logic/migrator.go
+++ b/go/logic/migrator.go
@@ -370,7 +370,6 @@ func (this *Migrator) Migrate() (err error) {
 	if err := this.initiateApplier(); err != nil {
 		return err
 	}
-
 	if err := this.createFlagFiles(); err != nil {
 		return err
 	}

From 9cbb42b92492757639c704e5c601ec5cac602909 Mon Sep 17 00:00:00 2001
From: dm-2 <45519614+dm-2@users.noreply.github.com>
Date: Mon, 14 Nov 2022 15:00:50 +0000
Subject: [PATCH 06/28] fix CI tests to ubuntu-20.04 because ubuntu-22.04
 (current -latest) doesn't support MySQL 5.7

---
 .github/workflows/ci.yml            | 2 +-
 .github/workflows/replica-tests.yml | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 8d5a07b..0b83bd7 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -5,7 +5,7 @@ on: [pull_request]
 jobs:
   build:
 
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
 
     steps:
     - uses: actions/checkout@v2
diff --git a/.github/workflows/replica-tests.yml b/.github/workflows/replica-tests.yml
index e28c2bc..0a82f00 100644
--- a/.github/workflows/replica-tests.yml
+++ b/.github/workflows/replica-tests.yml
@@ -5,7 +5,7 @@ on: [pull_request]
 jobs:
   build:
 
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     strategy:
       matrix:
         version: [mysql-5.7.25,mysql-8.0.16]

From 75a346be93a7ab3b9097fe05ef2451adeadccbdd Mon Sep 17 00:00:00 2001
From: Morgan Tocker <mtocker@squareup.com>
Date: Mon, 14 Nov 2022 11:29:26 -0700
Subject: [PATCH 07/28] Add tests, incorporate feedback

---
 doc/command-line-flags.md                 | 16 +++++++++++
 go/cmd/gh-ost/main.go                     |  2 +-
 go/logic/applier.go                       | 33 ++++++++++++++---------
 go/logic/applier_test.go                  | 14 ++++++++++
 go/logic/migrator.go                      |  9 +++----
 localtests/attempt-instant-ddl/create.sql | 13 +++++++++
 localtests/attempt-instant-ddl/extra_args |  1 +
 7 files changed, 70 insertions(+), 18 deletions(-)
 create mode 100644 localtests/attempt-instant-ddl/create.sql
 create mode 100644 localtests/attempt-instant-ddl/extra_args

diff --git a/doc/command-line-flags.md b/doc/command-line-flags.md
index dc481d0..b496b04 100644
--- a/doc/command-line-flags.md
+++ b/doc/command-line-flags.md
@@ -45,6 +45,22 @@ If you happen to _know_ your servers use RBR (Row Based Replication, i.e. `binlo
 Skipping this step means `gh-ost` would not need the `SUPER` privilege in order to operate.
 You may want to use this on Amazon RDS.
 
+### attempt-instant-ddl
+
+MySQL 8.0 support "instant DDL" for some operations. If an alter statement can be completed with instant DDL, only a metadata change is required internally, so MySQL will return _instantly_ (only requiring a metadata lock to complete). Instant operations include:
+
+- Adding a column
+- Dropping a column
+- Dropping an index
+- Extending a varchar column
+- Adding a virtual generated column
+
+It is not reliable to parse the `ALTER` statement to determine if it is instant or not. This is because the table might be in an older row format, or have some other incompatibility that is difficult to identify.
+
+The risks of attempting to instant DDL are relatively minor: Gh-ost may need to acquire a metadata lock at the start of the operation. This is not a problem for most scenarios, but it could be a problem for users that start the DDL during a period with long running transactions.
+
+gh-ost will automatically fallback to the normal DDL process if the attempt to use instant DDL is unsuccessful.
+
 ### conf
 
 `--conf=/path/to/my.cnf`: file where credentials are specified. Should be in (or contain) the following format:
diff --git a/go/cmd/gh-ost/main.go b/go/cmd/gh-ost/main.go
index 660c492..c00b206 100644
--- a/go/cmd/gh-ost/main.go
+++ b/go/cmd/gh-ost/main.go
@@ -67,7 +67,7 @@ func main() {
 	flag.StringVar(&migrationContext.DatabaseName, "database", "", "database name (mandatory)")
 	flag.StringVar(&migrationContext.OriginalTableName, "table", "", "table name (mandatory)")
 	flag.StringVar(&migrationContext.AlterStatement, "alter", "", "alter statement (mandatory)")
-	flag.BoolVar(&migrationContext.AttemptInstantDDL, "attempt-instant-ddl", true, "Attempt to use instant DDL for this migration first.")
+	flag.BoolVar(&migrationContext.AttemptInstantDDL, "attempt-instant-ddl", false, "Attempt to use instant DDL for this migration first")
 
 	flag.BoolVar(&migrationContext.CountTableRows, "exact-rowcount", false, "actually count table rows as opposed to estimate them (results in more accurate progress estimation)")
 	flag.BoolVar(&migrationContext.ConcurrentCountTableRows, "concurrent-rowcount", true, "(with --exact-rowcount), when true (default): count rows after row-copy begins, concurrently, and adjust row estimate later on; when false: first count rows, then start row copy")
diff --git a/go/logic/applier.go b/go/logic/applier.go
index abda2b0..ad6368e 100644
--- a/go/logic/applier.go
+++ b/go/logic/applier.go
@@ -135,6 +135,16 @@ func (this *Applier) generateSqlModeQuery() string {
 	return fmt.Sprintf("sql_mode = %s", sqlModeQuery)
 }
 
+// generateInstantDDLQuery returns the SQL for this ALTER operation
+// with an INSTANT assertion (requires MySQL 8.0+)
+func (this *Applier) generateInstantDDLQuery() string {
+	return fmt.Sprintf(`ALTER /* gh-ost */ TABLE %s.%s %s, ALGORITHM=INSTANT`,
+		sql.EscapeName(this.migrationContext.DatabaseName),
+		sql.EscapeName(this.migrationContext.OriginalTableName),
+		this.migrationContext.AlterStatementOptions,
+	)
+}
+
 // readTableColumns reads table columns on applier
 func (this *Applier) readTableColumns() (err error) {
 	this.migrationContext.Log.Infof("Examining table structure on applier")
@@ -188,22 +198,21 @@ func (this *Applier) ValidateOrDropExistingTables() error {
 	return nil
 }
 
-// AttemptInstantDDL attempts to use instant DDL (from MySQL 8.0, and earlier in Aurora and some others.)
-// to apply the ALTER statement immediately. If it errors, the original
-// gh-ost algorithm can be used. However, if it's successful -- a lot
-// of time can potentially be saved. Instant operations include:
+// AttemptInstantDDL attempts to use instant DDL (from MySQL 8.0, and earlier in Aurora and some others).
+// If successful, the operation is only a meta-data change so a lot of time is saved!
+// The risk of attempting to instant DDL when not supported is that a metadata lock may be acquired.
+// This is minor, since gh-ost will eventually require a metadata lock anyway, but at the cut-over stage.
+// Instant operations include:
 // - Adding a column
 // - Dropping a column
 // - Dropping an index
-// - Extending a varchar column
-// It is safer to attempt the change than try and parse the DDL, since
-// there might be specifics about the table which make it not possible to apply instantly.
+// - Extending a VARCHAR column
+// - Adding a virtual generated column
+// It is not reliable to parse the `alter` statement to determine if it is instant or not.
+// This is because the table might be in an older row format, or have some other incompatibility
+// that is difficult to identify.
 func (this *Applier) AttemptInstantDDL() error {
-	query := fmt.Sprintf(`ALTER /* gh-ost */ TABLE %s.%s %s, ALGORITHM=INSTANT`,
-		sql.EscapeName(this.migrationContext.DatabaseName),
-		sql.EscapeName(this.migrationContext.OriginalTableName),
-		this.migrationContext.AlterStatementOptions,
-	)
+	query := this.generateInstantDDLQuery()
 	this.migrationContext.Log.Infof("INSTANT DDL query is: %s", query)
 	// We don't need a trx, because for instant DDL the SQL mode doesn't matter.
 	_, err := this.db.Exec(query)
diff --git a/go/logic/applier_test.go b/go/logic/applier_test.go
index a2c1414..44d1fc7 100644
--- a/go/logic/applier_test.go
+++ b/go/logic/applier_test.go
@@ -170,3 +170,17 @@ func TestApplierBuildDMLEventQuery(t *testing.T) {
 		test.S(t).ExpectEquals(res[0].args[3], 42)
 	})
 }
+
+func TestApplierInstantDDL(t *testing.T) {
+	migrationContext := base.NewMigrationContext()
+	migrationContext.DatabaseName = "test"
+	migrationContext.OriginalTableName = "mytable"
+	migrationContext.AlterStatementOptions = "ADD INDEX (foo)"
+	applier := NewApplier(migrationContext)
+
+	t.Run("instantDDLstmt", func(t *testing.T) {
+		stmt := applier.generateInstantDDLQuery()
+		test.S(t).ExpectEquals(stmt, "ALTER /* gh-ost */ TABLE `test`.`mytable` ADD INDEX (foo), ALGORITHM=INSTANT")
+	})
+
+}
diff --git a/go/logic/migrator.go b/go/logic/migrator.go
index 25989f8..13cbdee 100644
--- a/go/logic/migrator.go
+++ b/go/logic/migrator.go
@@ -352,15 +352,14 @@ func (this *Migrator) Migrate() (err error) {
 		return err
 	}
 	// In MySQL 8.0 (and possibly earlier) some DDL statements can be applied instantly.
-	// As just a metadata change. We can't detect this unless we attempt the statement
-	// (i.e. there is no explain for DDL).
+	// Attempt to do this if AttemptInstantDDL is set.
 	if this.migrationContext.AttemptInstantDDL {
-		this.migrationContext.Log.Infof("Attempting to execute ALTER TABLE as INSTANT DDL")
+		this.migrationContext.Log.Infof("Attempting to execute alter with ALGORITHM=INSTANT")
 		if err := this.attemptInstantDDL(); err == nil {
-			this.migrationContext.Log.Infof("Success! Table %s.%s migrated instantly", sql.EscapeName(this.migrationContext.DatabaseName), sql.EscapeName(this.migrationContext.OriginalTableName))
+			this.migrationContext.Log.Infof("Success! table %s.%s migrated instantly", sql.EscapeName(this.migrationContext.DatabaseName), sql.EscapeName(this.migrationContext.OriginalTableName))
 			return nil
 		} else {
-			this.migrationContext.Log.Infof("INSTANT DDL failed, will proceed with original algorithm: %s", err)
+			this.migrationContext.Log.Infof("ALGORITHM=INSTANT failed, proceeding with original algorithm: %s", err)
 		}
 	}
 
diff --git a/localtests/attempt-instant-ddl/create.sql b/localtests/attempt-instant-ddl/create.sql
new file mode 100644
index 0000000..9371238
--- /dev/null
+++ b/localtests/attempt-instant-ddl/create.sql
@@ -0,0 +1,13 @@
+drop table if exists gh_ost_test;
+create table gh_ost_test (
+  id int auto_increment,
+  i int not null,
+  color varchar(32),
+  primary key(id)
+) auto_increment=1;
+
+drop event if exists gh_ost_test;
+
+insert into gh_ost_test values (null, 11, 'red');
+insert into gh_ost_test values (null, 13, 'green');
+insert into gh_ost_test values (null, 17, 'blue');
diff --git a/localtests/attempt-instant-ddl/extra_args b/localtests/attempt-instant-ddl/extra_args
new file mode 100644
index 0000000..70c8a52
--- /dev/null
+++ b/localtests/attempt-instant-ddl/extra_args
@@ -0,0 +1 @@
+--attempt-instant-ddl

From b06c1cd498b31f601abe857b0b3bd5a4737aa586 Mon Sep 17 00:00:00 2001
From: Morgan Tocker <mtocker@squareup.com>
Date: Mon, 14 Nov 2022 12:30:38 -0700
Subject: [PATCH 08/28] Improve docs

---
 doc/command-line-flags.md | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/doc/command-line-flags.md b/doc/command-line-flags.md
index b496b04..509fa67 100644
--- a/doc/command-line-flags.md
+++ b/doc/command-line-flags.md
@@ -47,7 +47,7 @@ You may want to use this on Amazon RDS.
 
 ### attempt-instant-ddl
 
-MySQL 8.0 support "instant DDL" for some operations. If an alter statement can be completed with instant DDL, only a metadata change is required internally, so MySQL will return _instantly_ (only requiring a metadata lock to complete). Instant operations include:
+MySQL 8.0 supports "instant DDL" for some operations. If an alter statement can be completed with instant DDL, only a metadata change is required internally. Instant operations include:
 
 - Adding a column
 - Dropping a column
@@ -57,9 +57,9 @@ MySQL 8.0 support "instant DDL" for some operations. If an alter statement can b
 
 It is not reliable to parse the `ALTER` statement to determine if it is instant or not. This is because the table might be in an older row format, or have some other incompatibility that is difficult to identify.
 
-The risks of attempting to instant DDL are relatively minor: Gh-ost may need to acquire a metadata lock at the start of the operation. This is not a problem for most scenarios, but it could be a problem for users that start the DDL during a period with long running transactions.
+The risks of attempting instant DDL are relatively minor: `gh-ost` may need to acquire a metadata lock at the start of the operation. This is not a problem for most scenarios, but it could be a problem for users that start the DDL during a period with long running transactions.
 
-gh-ost will automatically fallback to the normal DDL process if the attempt to use instant DDL is unsuccessful.
+`gh-ost` will automatically fallback to the normal DDL process if the attempt to use instant DDL is unsuccessful.
 
 ### conf
 

From 3f3a10a2133ae7318536f260bcdbd42ad700e2b0 Mon Sep 17 00:00:00 2001
From: Morgan Tocker <mtocker@squareup.com>
Date: Mon, 14 Nov 2022 14:47:00 -0700
Subject: [PATCH 09/28] Address PR feedback

---
 go/logic/applier_test.go |  1 -
 go/logic/migrator.go     | 23 +++++++++--------------
 2 files changed, 9 insertions(+), 15 deletions(-)

diff --git a/go/logic/applier_test.go b/go/logic/applier_test.go
index 44d1fc7..a356351 100644
--- a/go/logic/applier_test.go
+++ b/go/logic/applier_test.go
@@ -182,5 +182,4 @@ func TestApplierInstantDDL(t *testing.T) {
 		stmt := applier.generateInstantDDLQuery()
 		test.S(t).ExpectEquals(stmt, "ALTER /* gh-ost */ TABLE `test`.`mytable` ADD INDEX (foo), ALGORITHM=INSTANT")
 	})
-
 }
diff --git a/go/logic/migrator.go b/go/logic/migrator.go
index 0dcf53f..31e21cc 100644
--- a/go/logic/migrator.go
+++ b/go/logic/migrator.go
@@ -351,6 +351,15 @@ func (this *Migrator) Migrate() (err error) {
 	if err := this.initiateInspector(); err != nil {
 		return err
 	}
+	if err := this.initiateStreaming(); err != nil {
+		return err
+	}
+	if err := this.initiateApplier(); err != nil {
+		return err
+	}
+	if err := this.createFlagFiles(); err != nil {
+		return err
+	}
 	// In MySQL 8.0 (and possibly earlier) some DDL statements can be applied instantly.
 	// Attempt to do this if AttemptInstantDDL is set.
 	if this.migrationContext.AttemptInstantDDL {
@@ -363,16 +372,6 @@ func (this *Migrator) Migrate() (err error) {
 		}
 	}
 
-	if err := this.initiateStreaming(); err != nil {
-		return err
-	}
-	if err := this.initiateApplier(); err != nil {
-		return err
-	}
-	if err := this.createFlagFiles(); err != nil {
-		return err
-	}
-
 	initialLag, _ := this.inspector.getReplicationLag()
 	this.migrationContext.Log.Infof("Waiting for ghost table to be migrated. Current lag is %+v", initialLag)
 	<-this.ghostTableMigrated
@@ -750,10 +749,6 @@ func (this *Migrator) initiateServer() (err error) {
 // using a ALGORITHM=INSTANT assertion. If this fails, it will return an error,
 // in which case the original algorithm should be used.
 func (this *Migrator) attemptInstantDDL() (err error) {
-	this.applier = NewApplier(this.migrationContext)
-	if err := this.applier.InitDBConnections(); err != nil {
-		return err
-	}
 	return this.applier.AttemptInstantDDL()
 }
 

From 1b22f784e3858b21767c78c6f74547db23e90266 Mon Sep 17 00:00:00 2001
From: dm-2 <45519614+dm-2@users.noreply.github.com>
Date: Tue, 15 Nov 2022 15:06:19 +0000
Subject: [PATCH 10/28] temp commit to investigate datetime-with-zero test
 failure

---
 script/cibuild-gh-ost-replica-tests | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/script/cibuild-gh-ost-replica-tests b/script/cibuild-gh-ost-replica-tests
index c4dbfd2..bc8b788 100755
--- a/script/cibuild-gh-ost-replica-tests
+++ b/script/cibuild-gh-ost-replica-tests
@@ -61,7 +61,7 @@ test_mysql_version() {
   gh-ost-test-mysql-master -uroot -e "grant all on *.* to 'gh-ost'@'%'"
 
   echo "### Running gh-ost tests for $mysql_version"
-  ./localtests/test.sh -b bin/gh-ost
+  bash ./localtests/test.sh -b bin/gh-ost datetime-with-zero
 
   find sandboxes -name "stop_all" | bash
 }

From 512751968feb38cea5995c908540d9fe5f583766 Mon Sep 17 00:00:00 2001
From: dm-2 <45519614+dm-2@users.noreply.github.com>
Date: Tue, 15 Nov 2022 16:01:54 +0000
Subject: [PATCH 11/28] more testing

---
 script/cibuild-gh-ost-replica-tests | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/script/cibuild-gh-ost-replica-tests b/script/cibuild-gh-ost-replica-tests
index bc8b788..0c37b27 100755
--- a/script/cibuild-gh-ost-replica-tests
+++ b/script/cibuild-gh-ost-replica-tests
@@ -61,7 +61,7 @@ test_mysql_version() {
   gh-ost-test-mysql-master -uroot -e "grant all on *.* to 'gh-ost'@'%'"
 
   echo "### Running gh-ost tests for $mysql_version"
-  bash ./localtests/test.sh -b bin/gh-ost datetime-with-zero
+  bash -x ./localtests/test.sh -b bin/gh-ost
 
   find sandboxes -name "stop_all" | bash
 }

From 74fb8e80b2a0f848a265b34f04ca8dbfb265743f Mon Sep 17 00:00:00 2001
From: Morgan Tocker <tocker@gmail.com>
Date: Tue, 15 Nov 2022 12:05:27 -0700
Subject: [PATCH 12/28] Update go/logic/migrator.go

Co-authored-by: dm-2 <45519614+dm-2@users.noreply.github.com>
---
 go/logic/migrator.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/go/logic/migrator.go b/go/logic/migrator.go
index 31e21cc..0f4ebba 100644
--- a/go/logic/migrator.go
+++ b/go/logic/migrator.go
@@ -368,7 +368,7 @@ func (this *Migrator) Migrate() (err error) {
 			this.migrationContext.Log.Infof("Success! table %s.%s migrated instantly", sql.EscapeName(this.migrationContext.DatabaseName), sql.EscapeName(this.migrationContext.OriginalTableName))
 			return nil
 		} else {
-			this.migrationContext.Log.Infof("ALGORITHM=INSTANT failed, proceeding with original algorithm: %s", err)
+			this.migrationContext.Log.Infof("ALGORITHM=INSTANT not supported for this operation, proceeding with original algorithm: %s", err)
 		}
 	}
 

From 5283b46ec23c494b4b4256b2e5a43d0b9e4f8974 Mon Sep 17 00:00:00 2001
From: Morgan Tocker <mtocker@squareup.com>
Date: Tue, 15 Nov 2022 12:06:11 -0700
Subject: [PATCH 13/28] Make it clear in docs it is disabled by default but
 safe.

---
 doc/command-line-flags.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/command-line-flags.md b/doc/command-line-flags.md
index 509fa67..56bc642 100644
--- a/doc/command-line-flags.md
+++ b/doc/command-line-flags.md
@@ -57,7 +57,7 @@ MySQL 8.0 supports "instant DDL" for some operations. If an alter statement can
 
 It is not reliable to parse the `ALTER` statement to determine if it is instant or not. This is because the table might be in an older row format, or have some other incompatibility that is difficult to identify.
 
-The risks of attempting instant DDL are relatively minor: `gh-ost` may need to acquire a metadata lock at the start of the operation. This is not a problem for most scenarios, but it could be a problem for users that start the DDL during a period with long running transactions.
+`--attempt-instant-ddl` is disabled by default, but the risks of enabling it are relatively minor: `gh-ost` may need to acquire a metadata lock at the start of the operation. This is not a problem for most scenarios, but it could be a problem for users that start the DDL during a period with long running transactions.
 
 `gh-ost` will automatically fallback to the normal DDL process if the attempt to use instant DDL is unsuccessful.
 

From 59c1a24774482723f100f1213bb16b16497b40f6 Mon Sep 17 00:00:00 2001
From: Morgan Tocker <mtocker@squareup.com>
Date: Tue, 15 Nov 2022 15:40:21 -0700
Subject: [PATCH 14/28] remove useless func per review

---
 go/logic/migrator.go | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/go/logic/migrator.go b/go/logic/migrator.go
index 0f4ebba..a102188 100644
--- a/go/logic/migrator.go
+++ b/go/logic/migrator.go
@@ -364,7 +364,7 @@ func (this *Migrator) Migrate() (err error) {
 	// Attempt to do this if AttemptInstantDDL is set.
 	if this.migrationContext.AttemptInstantDDL {
 		this.migrationContext.Log.Infof("Attempting to execute alter with ALGORITHM=INSTANT")
-		if err := this.attemptInstantDDL(); err == nil {
+		if err := this.applier.AttemptInstantDDL(); err == nil {
 			this.migrationContext.Log.Infof("Success! table %s.%s migrated instantly", sql.EscapeName(this.migrationContext.DatabaseName), sql.EscapeName(this.migrationContext.OriginalTableName))
 			return nil
 		} else {
@@ -745,13 +745,6 @@ func (this *Migrator) initiateServer() (err error) {
 	return nil
 }
 
-// attemptInstantDDL tries to apply the DDL statement directly to the table
-// using a ALGORITHM=INSTANT assertion. If this fails, it will return an error,
-// in which case the original algorithm should be used.
-func (this *Migrator) attemptInstantDDL() (err error) {
-	return this.applier.AttemptInstantDDL()
-}
-
 // initiateInspector connects, validates and inspects the "inspector" server.
 // The "inspector" server is typically a replica; it is where we issue some
 // queries such as:

From cd65c7e9ada627e0fec413ff1ac6a8e7822ac88c Mon Sep 17 00:00:00 2001
From: dm-2 <45519614+dm-2@users.noreply.github.com>
Date: Fri, 18 Nov 2022 15:11:44 +0000
Subject: [PATCH 15/28] add extra debugging output

---
 localtests/test.sh | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/localtests/test.sh b/localtests/test.sh
index f66c813..a3c8fa4 100755
--- a/localtests/test.sh
+++ b/localtests/test.sh
@@ -116,7 +116,8 @@ test_single() {
     gh-ost-test-mysql-replica --default-character-set=utf8mb4 test -e "set @@global.sql_mode='$(cat $tests_path/$test_name/sql_mode)'"
   fi
 
-  gh-ost-test-mysql-master --default-character-set=utf8mb4 test < $tests_path/$test_name/create.sql
+  cat $tests_path/$test_name/create.sql
+  bash -x gh-ost-test-mysql-master --default-character-set=utf8mb4 test < $tests_path/$test_name/create.sql
 
   extra_args=""
   if [ -f $tests_path/$test_name/extra_args ] ; then

From 7cebc16c6fc56e168f9732a152afa54f9d71a6ae Mon Sep 17 00:00:00 2001
From: dm-2 <45519614+dm-2@users.noreply.github.com>
Date: Fri, 18 Nov 2022 15:32:34 +0000
Subject: [PATCH 16/28] debugging

---
 localtests/test.sh | 1 +
 1 file changed, 1 insertion(+)

diff --git a/localtests/test.sh b/localtests/test.sh
index a3c8fa4..b953861 100755
--- a/localtests/test.sh
+++ b/localtests/test.sh
@@ -118,6 +118,7 @@ test_single() {
 
   cat $tests_path/$test_name/create.sql
   bash -x gh-ost-test-mysql-master --default-character-set=utf8mb4 test < $tests_path/$test_name/create.sql
+  echo $?
 
   extra_args=""
   if [ -f $tests_path/$test_name/extra_args ] ; then

From 756f3d30e8d4252f30f5e7a8721a158e789355d6 Mon Sep 17 00:00:00 2001
From: dm-2 <45519614+dm-2@users.noreply.github.com>
Date: Fri, 18 Nov 2022 15:44:14 +0000
Subject: [PATCH 17/28] add error detection for test setup, sort tests to make
 it easier to track progress

---
 localtests/test.sh                  | 14 ++++++++++----
 script/cibuild-gh-ost-replica-tests |  2 +-
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/localtests/test.sh b/localtests/test.sh
index b953861..5ca06ad 100755
--- a/localtests/test.sh
+++ b/localtests/test.sh
@@ -116,9 +116,15 @@ test_single() {
     gh-ost-test-mysql-replica --default-character-set=utf8mb4 test -e "set @@global.sql_mode='$(cat $tests_path/$test_name/sql_mode)'"
   fi
 
-  cat $tests_path/$test_name/create.sql
-  bash -x gh-ost-test-mysql-master --default-character-set=utf8mb4 test < $tests_path/$test_name/create.sql
-  echo $?
+  gh-ost-test-mysql-master --default-character-set=utf8mb4 test < $tests_path/$test_name/create.sql
+  test_create_result=$?
+
+  if [ $test_create_result -ne 0 ] ; then
+    echo
+    echo "ERROR $test_name create failure. cat $tests_path/$test_name/create.sql:"
+    cat $tests_path/$test_name/create.sql
+    return 1
+  fi
 
   extra_args=""
   if [ -f $tests_path/$test_name/extra_args ] ; then
@@ -257,7 +263,7 @@ build_binary() {
 
 test_all() {
   build_binary
-  find $tests_path ! -path . -type d -mindepth 1 -maxdepth 1 | cut -d "/" -f 3 | egrep "$test_pattern" | while read test_name ; do
+  find $tests_path ! -path . -type d -mindepth 1 -maxdepth 1 | cut -d "/" -f 3 | egrep "$test_pattern" | sort | while read test_name ; do
     test_single "$test_name"
     if [ $? -ne 0 ] ; then
       create_statement=$(gh-ost-test-mysql-replica test -t -e "show create table _gh_ost_test_gho \G")
diff --git a/script/cibuild-gh-ost-replica-tests b/script/cibuild-gh-ost-replica-tests
index 0c37b27..c4dbfd2 100755
--- a/script/cibuild-gh-ost-replica-tests
+++ b/script/cibuild-gh-ost-replica-tests
@@ -61,7 +61,7 @@ test_mysql_version() {
   gh-ost-test-mysql-master -uroot -e "grant all on *.* to 'gh-ost'@'%'"
 
   echo "### Running gh-ost tests for $mysql_version"
-  bash -x ./localtests/test.sh -b bin/gh-ost
+  ./localtests/test.sh -b bin/gh-ost
 
   find sandboxes -name "stop_all" | bash
 }

From 8abd58482651750fc68f9541b76b07b6a16ae50d Mon Sep 17 00:00:00 2001
From: dm-2 <45519614+dm-2@users.noreply.github.com>
Date: Fri, 18 Nov 2022 15:49:04 +0000
Subject: [PATCH 18/28] fix broken test by removing invalid insert statement

---
 localtests/convert-utf8mb4/create.sql | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/localtests/convert-utf8mb4/create.sql b/localtests/convert-utf8mb4/create.sql
index 05f1a13..e35e688 100644
--- a/localtests/convert-utf8mb4/create.sql
+++ b/localtests/convert-utf8mb4/create.sql
@@ -7,9 +7,6 @@ create table gh_ost_test (
   primary key(id)
 ) auto_increment=1;
 
-insert into gh_ost_test values (null, 'átesting');
-
-
 insert into gh_ost_test values (null, 'Hello world, Καλημέρα κόσμε, コンニチハ', 'átesting0', 'initial');
 
 drop event if exists gh_ost_test;

From f053ccd9a6002cabd18105ea2c207f9f62960642 Mon Sep 17 00:00:00 2001
From: lukelewang <lukelewang@tencent.com>
Date: Wed, 23 Nov 2022 17:32:53 +0800
Subject: [PATCH 19/28] support rocksdb as transactional engine

---
 doc/command-line-flags.md   |  3 +++
 go/base/context.go          | 17 +++++++++++++++--
 go/cmd/gh-ost/main.go       |  5 +++++
 go/mysql/connection.go      |  7 ++++---
 go/mysql/connection_test.go | 15 ++++++++++-----
 5 files changed, 37 insertions(+), 10 deletions(-)

diff --git a/doc/command-line-flags.md b/doc/command-line-flags.md
index 56bc642..5a61631 100644
--- a/doc/command-line-flags.md
+++ b/doc/command-line-flags.md
@@ -246,6 +246,9 @@ Allows `gh-ost` to connect to the MySQL servers using encrypted connections, but
 
 `--ssl-key=/path/to/ssl-key.key`: SSL private key file (in PEM format).
 
+### storage-engine
+default is `innodb`. When set to `rocksdb`, some necessary changes (e.g. sets isolation level to READ_COMMITTED) is made to support rocksdb as transactional engine. 
+
 ### test-on-replica
 
 Issue the migration on a replica; do not modify data on master. Useful for validating, testing and benchmarking. See [`testing-on-replica`](testing-on-replica.md)
diff --git a/go/base/context.go b/go/base/context.go
index 7089874..cc5844e 100644
--- a/go/base/context.go
+++ b/go/base/context.go
@@ -270,8 +270,6 @@ func NewMigrationContext() *MigrationContext {
 		Uuid:                                uuid.NewV4().String(),
 		defaultNumRetries:                   60,
 		ChunkSize:                           1000,
-		InspectorConnectionConfig:           mysql.NewConnectionConfig(),
-		ApplierConnectionConfig:             mysql.NewConnectionConfig(),
 		MaxLagMillisecondsThrottleThreshold: 1500,
 		CutOverLockTimeoutSeconds:           3,
 		DMLBatchSize:                        10,
@@ -290,6 +288,21 @@ func NewMigrationContext() *MigrationContext {
 	}
 }
 
+func (this *MigrationContext) SetConnectionConfig(storageEngine string) error {
+	transactionIsolation := "REPEATABLE-READ"
+	switch storageEngine {
+	case "rocksdb":
+		transactionIsolation = "READ-COMMITTED"
+	case "innodb":
+		transactionIsolation = "REPEATABLE-READ"
+	default:
+		transactionIsolation = "REPEATABLE-READ"
+	}
+	this.InspectorConnectionConfig = mysql.NewConnectionConfig(transactionIsolation)
+	this.ApplierConnectionConfig = mysql.NewConnectionConfig(transactionIsolation)
+	return nil
+}
+
 func getSafeTableName(baseName string, suffix string) string {
 	name := fmt.Sprintf("_%s_%s", baseName, suffix)
 	if len(name) <= mysql.MaxTableNameLength {
diff --git a/go/cmd/gh-ost/main.go b/go/cmd/gh-ost/main.go
index c00b206..54083c3 100644
--- a/go/cmd/gh-ost/main.go
+++ b/go/cmd/gh-ost/main.go
@@ -68,6 +68,7 @@ func main() {
 	flag.StringVar(&migrationContext.OriginalTableName, "table", "", "table name (mandatory)")
 	flag.StringVar(&migrationContext.AlterStatement, "alter", "", "alter statement (mandatory)")
 	flag.BoolVar(&migrationContext.AttemptInstantDDL, "attempt-instant-ddl", false, "Attempt to use instant DDL for this migration first")
+	storageEngine := flag.String("storage-engine", "innodb", "Specify table storage engine (default: 'innodb'). When 'rocksdb': change session transaction isolation level to READ_COMMITTED.")
 
 	flag.BoolVar(&migrationContext.CountTableRows, "exact-rowcount", false, "actually count table rows as opposed to estimate them (results in more accurate progress estimation)")
 	flag.BoolVar(&migrationContext.ConcurrentCountTableRows, "concurrent-rowcount", true, "(with --exact-rowcount), when true (default): count rows after row-copy begins, concurrently, and adjust row estimate later on; when false: first count rows, then start row copy")
@@ -248,6 +249,10 @@ func main() {
 		migrationContext.Log.Warning("--replication-lag-query is deprecated")
 	}
 
+	if err := migrationContext.SetConnectionConfig(*storageEngine); err != nil {
+		migrationContext.Log.Fatale(err)
+	}
+
 	switch *cutOver {
 	case "atomic", "default", "":
 		migrationContext.CutOverType = base.CutOverAtomic
diff --git a/go/mysql/connection.go b/go/mysql/connection.go
index 6a5c890..dcf33ad 100644
--- a/go/mysql/connection.go
+++ b/go/mysql/connection.go
@@ -18,7 +18,6 @@ import (
 )
 
 const (
-	transactionIsolation = "REPEATABLE-READ"
 	TLS_CONFIG_KEY       = "ghost"
 )
 
@@ -30,11 +29,13 @@ type ConnectionConfig struct {
 	ImpliedKey *InstanceKey
 	tlsConfig  *tls.Config
 	Timeout    float64
+	transactionIsolation string
 }
 
-func NewConnectionConfig() *ConnectionConfig {
+func NewConnectionConfig(transactionIsolation string) *ConnectionConfig {
 	config := &ConnectionConfig{
 		Key: InstanceKey{},
+		transactionIsolation: transactionIsolation,
 	}
 	config.ImpliedKey = &config.Key
 	return config
@@ -126,7 +127,7 @@ func (this *ConnectionConfig) GetDBUri(databaseName string) string {
 		"charset=utf8mb4,utf8,latin1",
 		"interpolateParams=true",
 		fmt.Sprintf("tls=%s", tlsOption),
-		fmt.Sprintf("transaction_isolation=%q", transactionIsolation),
+		fmt.Sprintf("transaction_isolation=%q", this.transactionIsolation),
 		fmt.Sprintf("timeout=%fs", this.Timeout),
 		fmt.Sprintf("readTimeout=%fs", this.Timeout),
 		fmt.Sprintf("writeTimeout=%fs", this.Timeout),
diff --git a/go/mysql/connection_test.go b/go/mysql/connection_test.go
index 390774c..2f39c4f 100644
--- a/go/mysql/connection_test.go
+++ b/go/mysql/connection_test.go
@@ -13,12 +13,17 @@ import (
 	test "github.com/openark/golib/tests"
 )
 
+const (
+	transactionIsolation = "REPEATABLE-READ"
+)
+
+
 func init() {
 	log.SetLevel(log.ERROR)
 }
 
 func TestNewConnectionConfig(t *testing.T) {
-	c := NewConnectionConfig()
+	c := NewConnectionConfig(transactionIsolation)
 	test.S(t).ExpectEquals(c.Key.Hostname, "")
 	test.S(t).ExpectEquals(c.Key.Port, 0)
 	test.S(t).ExpectEquals(c.ImpliedKey.Hostname, "")
@@ -28,7 +33,7 @@ func TestNewConnectionConfig(t *testing.T) {
 }
 
 func TestDuplicateCredentials(t *testing.T) {
-	c := NewConnectionConfig()
+	c := NewConnectionConfig(transactionIsolation)
 	c.Key = InstanceKey{Hostname: "myhost", Port: 3306}
 	c.User = "gromit"
 	c.Password = "penguin"
@@ -48,7 +53,7 @@ func TestDuplicateCredentials(t *testing.T) {
 }
 
 func TestDuplicate(t *testing.T) {
-	c := NewConnectionConfig()
+	c := NewConnectionConfig(transactionIsolation)
 	c.Key = InstanceKey{Hostname: "myhost", Port: 3306}
 	c.User = "gromit"
 	c.Password = "penguin"
@@ -63,7 +68,7 @@ func TestDuplicate(t *testing.T) {
 }
 
 func TestGetDBUri(t *testing.T) {
-	c := NewConnectionConfig()
+	c := NewConnectionConfig(transactionIsolation)
 	c.Key = InstanceKey{Hostname: "myhost", Port: 3306}
 	c.User = "gromit"
 	c.Password = "penguin"
@@ -74,7 +79,7 @@ func TestGetDBUri(t *testing.T) {
 }
 
 func TestGetDBUriWithTLSSetup(t *testing.T) {
-	c := NewConnectionConfig()
+	c := NewConnectionConfig(transactionIsolation)
 	c.Key = InstanceKey{Hostname: "myhost", Port: 3306}
 	c.User = "gromit"
 	c.Password = "penguin"

From 3ee667a40e3495ce9842e879d6b46e0e76ad437e Mon Sep 17 00:00:00 2001
From: lukelewang <lukelewang@tencent.com>
Date: Fri, 25 Nov 2022 17:18:32 +0800
Subject: [PATCH 20/28] Modify tests to support rocksdb tests

---
 localtests/discard-fk/ignore_versions         |  1 +
 localtests/fail-fk-parent/ignore_versions     |  1 +
 localtests/fail-fk/ignore_versions            |  1 +
 .../generated-columns-add/ignore_versions     |  1 +
 .../generated-columns-rename/ignore_versions  |  1 +
 .../generated-columns-unique/ignore_versions  |  1 +
 localtests/generated-columns/ignore_versions  |  1 +
 localtests/geometry/ignore_versions           |  1 +
 localtests/spatial/ignore_versions            |  1 +
 localtests/test.sh                            |  4 ++
 script/cibuild-gh-ost-replica-tests           | 40 +++++++++++++++++++
 11 files changed, 53 insertions(+)
 create mode 100644 localtests/discard-fk/ignore_versions
 create mode 100644 localtests/fail-fk-parent/ignore_versions
 create mode 100644 localtests/fail-fk/ignore_versions
 create mode 100644 localtests/generated-columns-add/ignore_versions
 create mode 100644 localtests/generated-columns-rename/ignore_versions
 create mode 100644 localtests/generated-columns-unique/ignore_versions
 create mode 100644 localtests/generated-columns/ignore_versions
 create mode 100644 localtests/geometry/ignore_versions
 create mode 100644 localtests/spatial/ignore_versions

diff --git a/localtests/discard-fk/ignore_versions b/localtests/discard-fk/ignore_versions
new file mode 100644
index 0000000..cf02abe
--- /dev/null
+++ b/localtests/discard-fk/ignore_versions
@@ -0,0 +1 @@
+Percona
\ No newline at end of file
diff --git a/localtests/fail-fk-parent/ignore_versions b/localtests/fail-fk-parent/ignore_versions
new file mode 100644
index 0000000..cf02abe
--- /dev/null
+++ b/localtests/fail-fk-parent/ignore_versions
@@ -0,0 +1 @@
+Percona
\ No newline at end of file
diff --git a/localtests/fail-fk/ignore_versions b/localtests/fail-fk/ignore_versions
new file mode 100644
index 0000000..cf02abe
--- /dev/null
+++ b/localtests/fail-fk/ignore_versions
@@ -0,0 +1 @@
+Percona
\ No newline at end of file
diff --git a/localtests/generated-columns-add/ignore_versions b/localtests/generated-columns-add/ignore_versions
new file mode 100644
index 0000000..cf02abe
--- /dev/null
+++ b/localtests/generated-columns-add/ignore_versions
@@ -0,0 +1 @@
+Percona
\ No newline at end of file
diff --git a/localtests/generated-columns-rename/ignore_versions b/localtests/generated-columns-rename/ignore_versions
new file mode 100644
index 0000000..cf02abe
--- /dev/null
+++ b/localtests/generated-columns-rename/ignore_versions
@@ -0,0 +1 @@
+Percona
\ No newline at end of file
diff --git a/localtests/generated-columns-unique/ignore_versions b/localtests/generated-columns-unique/ignore_versions
new file mode 100644
index 0000000..cf02abe
--- /dev/null
+++ b/localtests/generated-columns-unique/ignore_versions
@@ -0,0 +1 @@
+Percona
\ No newline at end of file
diff --git a/localtests/generated-columns/ignore_versions b/localtests/generated-columns/ignore_versions
new file mode 100644
index 0000000..cf02abe
--- /dev/null
+++ b/localtests/generated-columns/ignore_versions
@@ -0,0 +1 @@
+Percona
\ No newline at end of file
diff --git a/localtests/geometry/ignore_versions b/localtests/geometry/ignore_versions
new file mode 100644
index 0000000..cf02abe
--- /dev/null
+++ b/localtests/geometry/ignore_versions
@@ -0,0 +1 @@
+Percona
\ No newline at end of file
diff --git a/localtests/spatial/ignore_versions b/localtests/spatial/ignore_versions
new file mode 100644
index 0000000..cf02abe
--- /dev/null
+++ b/localtests/spatial/ignore_versions
@@ -0,0 +1 @@
+Percona
\ No newline at end of file
diff --git a/localtests/test.sh b/localtests/test.sh
index 5ca06ad..d73dab2 100755
--- a/localtests/test.sh
+++ b/localtests/test.sh
@@ -99,9 +99,13 @@ test_single() {
   if [ -f $tests_path/$test_name/ignore_versions ] ; then
     ignore_versions=$(cat $tests_path/$test_name/ignore_versions)
     mysql_version=$(gh-ost-test-mysql-master -s -s -e "select @@version")
+    mysql_version_comment=$(gh-ost-test-mysql-master -s -s -e "select @@version_comment")
     if echo "$mysql_version" | egrep -q "^${ignore_versions}" ; then
       echo -n "Skipping: $test_name"
       return 0
+    elif echo "$mysql_version_comment" | egrep -i -q "^${ignore_versions}" ; then
+      echo -n "Skipping: $test_name"
+      return 0
     fi
   fi
 
diff --git a/script/cibuild-gh-ost-replica-tests b/script/cibuild-gh-ost-replica-tests
index c4dbfd2..bb60d71 100755
--- a/script/cibuild-gh-ost-replica-tests
+++ b/script/cibuild-gh-ost-replica-tests
@@ -60,6 +60,46 @@ test_mysql_version() {
   gh-ost-test-mysql-master -uroot -e "create user 'gh-ost'@'%' identified by 'gh-ost'"
   gh-ost-test-mysql-master -uroot -e "grant all on *.* to 'gh-ost'@'%'"
 
+  local mysql_server=${mysql_version%-*}
+  if echo "$mysql_server" | egrep -i "percona" ; then
+    echo "### Preparing for rocksdb in PerconaServer"
+    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_CFSTATS SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_DBSTATS SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_PERF_CONTEXT SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_PERF_CONTEXT_GLOBAL SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_CF_OPTIONS SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_GLOBAL_INFO SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_COMPACTION_HISTORY SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_COMPACTION_STATS SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_ACTIVE_COMPACTION_STATS SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_DDL SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_INDEX_FILE_MAP SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_LOCKS SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_TRX SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_DEADLOCK SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-master -uroot -e "set global default_storage_engine='ROCKSDB'"
+    gh-ost-test-mysql-master -uroot -e "set global transaction_isolation='READ-COMMITTED'"
+
+    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_CFSTATS SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_DBSTATS SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_PERF_CONTEXT SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_PERF_CONTEXT_GLOBAL SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_CF_OPTIONS SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_GLOBAL_INFO SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_COMPACTION_HISTORY SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_COMPACTION_STATS SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_ACTIVE_COMPACTION_STATS SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_DDL SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_INDEX_FILE_MAP SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_LOCKS SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_TRX SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_DEADLOCK SONAME 'ha_rocksdb.so'"
+    gh-ost-test-mysql-replica -uroot -e "set global default_storage_engine='ROCKSDB'"
+    gh-ost-test-mysql-replica -uroot -e "set global transaction_isolation='READ-COMMITTED'"
+  fi
+
   echo "### Running gh-ost tests for $mysql_version"
   ./localtests/test.sh -b bin/gh-ost
 

From ccf5b2e01df93ce1d0df9ca3b5bb199dc7c46fb2 Mon Sep 17 00:00:00 2001
From: wangzihuacool <wangzihuacool@163.com>
Date: Fri, 25 Nov 2022 09:39:57 +0000
Subject: [PATCH 21/28] gofmt

---
 go/mysql/connection.go      | 16 ++++++++--------
 go/mysql/connection_test.go |  1 -
 2 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/go/mysql/connection.go b/go/mysql/connection.go
index dcf33ad..15d7cb0 100644
--- a/go/mysql/connection.go
+++ b/go/mysql/connection.go
@@ -18,23 +18,23 @@ import (
 )
 
 const (
-	TLS_CONFIG_KEY       = "ghost"
+	TLS_CONFIG_KEY = "ghost"
 )
 
 // ConnectionConfig is the minimal configuration required to connect to a MySQL server
 type ConnectionConfig struct {
-	Key        InstanceKey
-	User       string
-	Password   string
-	ImpliedKey *InstanceKey
-	tlsConfig  *tls.Config
-	Timeout    float64
+	Key                  InstanceKey
+	User                 string
+	Password             string
+	ImpliedKey           *InstanceKey
+	tlsConfig            *tls.Config
+	Timeout              float64
 	transactionIsolation string
 }
 
 func NewConnectionConfig(transactionIsolation string) *ConnectionConfig {
 	config := &ConnectionConfig{
-		Key: InstanceKey{},
+		Key:                  InstanceKey{},
 		transactionIsolation: transactionIsolation,
 	}
 	config.ImpliedKey = &config.Key
diff --git a/go/mysql/connection_test.go b/go/mysql/connection_test.go
index 2f39c4f..e8cdc27 100644
--- a/go/mysql/connection_test.go
+++ b/go/mysql/connection_test.go
@@ -17,7 +17,6 @@ const (
 	transactionIsolation = "REPEATABLE-READ"
 )
 
-
 func init() {
 	log.SetLevel(log.ERROR)
 }

From 9c7857bd469b204399923a102c2ab120495d01c9 Mon Sep 17 00:00:00 2001
From: lukelewang <lukelewang@tencent.com>
Date: Fri, 25 Nov 2022 18:48:48 +0800
Subject: [PATCH 22/28] SetConnectionConfig

---
 go/base/context.go          |  5 ++++-
 go/cmd/gh-ost/main.go       | 14 +++++++-------
 go/mysql/connection.go      | 16 ++++++++--------
 go/mysql/connection_test.go |  1 -
 4 files changed, 19 insertions(+), 17 deletions(-)

diff --git a/go/base/context.go b/go/base/context.go
index cc5844e..b68bf7b 100644
--- a/go/base/context.go
+++ b/go/base/context.go
@@ -288,7 +288,7 @@ func NewMigrationContext() *MigrationContext {
 	}
 }
 
-func (this *MigrationContext) SetConnectionConfig(storageEngine string) error {
+func (this *MigrationContext) SetConnectionConfig(storageEngine string, host string, port int, timeout float64) error {
 	transactionIsolation := "REPEATABLE-READ"
 	switch storageEngine {
 	case "rocksdb":
@@ -299,6 +299,9 @@ func (this *MigrationContext) SetConnectionConfig(storageEngine string) error {
 		transactionIsolation = "REPEATABLE-READ"
 	}
 	this.InspectorConnectionConfig = mysql.NewConnectionConfig(transactionIsolation)
+	this.InspectorConnectionConfig.Key.Hostname = host
+	this.InspectorConnectionConfig.Key.Port = port
+	this.InspectorConnectionConfig.Timeout = timeout
 	this.ApplierConnectionConfig = mysql.NewConnectionConfig(transactionIsolation)
 	return nil
 }
diff --git a/go/cmd/gh-ost/main.go b/go/cmd/gh-ost/main.go
index 54083c3..145ef65 100644
--- a/go/cmd/gh-ost/main.go
+++ b/go/cmd/gh-ost/main.go
@@ -47,10 +47,10 @@ func acceptSignals(migrationContext *base.MigrationContext) {
 // main is the application's entry point. It will either spawn a CLI or HTTP interfaces.
 func main() {
 	migrationContext := base.NewMigrationContext()
-	flag.StringVar(&migrationContext.InspectorConnectionConfig.Key.Hostname, "host", "127.0.0.1", "MySQL hostname (preferably a replica, not the master)")
+	host := flag.String("host", "127.0.0.1", "MySQL hostname (preferably a replica, not the master)")
+	port := flag.Int("port", 3306, "MySQL port (preferably a replica, not the master)")
+	timeout := flag.Float64("mysql-timeout", 0.0, "Connect, read and write timeout for MySQL")
 	flag.StringVar(&migrationContext.AssumeMasterHostname, "assume-master-host", "", "(optional) explicitly tell gh-ost the identity of the master. Format: some.host.com[:port] This is useful in master-master setups where you wish to pick an explicit master, or in a tungsten-replicator where gh-ost is unable to determine the master")
-	flag.IntVar(&migrationContext.InspectorConnectionConfig.Key.Port, "port", 3306, "MySQL port (preferably a replica, not the master)")
-	flag.Float64Var(&migrationContext.InspectorConnectionConfig.Timeout, "mysql-timeout", 0.0, "Connect, read and write timeout for MySQL")
 	flag.StringVar(&migrationContext.CliUser, "user", "", "MySQL user")
 	flag.StringVar(&migrationContext.CliPassword, "password", "", "MySQL password")
 	flag.StringVar(&migrationContext.CliMasterUser, "master-user", "", "MySQL user on master, if different from that on replica. Requires --assume-master-host")
@@ -183,6 +183,10 @@ func main() {
 		migrationContext.Log.SetLevel(log.ERROR)
 	}
 
+	if err := migrationContext.SetConnectionConfig(*storageEngine, *host, *port, *timeout); err != nil {
+		migrationContext.Log.Fatale(err)
+	}
+
 	if migrationContext.AlterStatement == "" {
 		log.Fatal("--alter must be provided and statement must not be empty")
 	}
@@ -249,10 +253,6 @@ func main() {
 		migrationContext.Log.Warning("--replication-lag-query is deprecated")
 	}
 
-	if err := migrationContext.SetConnectionConfig(*storageEngine); err != nil {
-		migrationContext.Log.Fatale(err)
-	}
-
 	switch *cutOver {
 	case "atomic", "default", "":
 		migrationContext.CutOverType = base.CutOverAtomic
diff --git a/go/mysql/connection.go b/go/mysql/connection.go
index dcf33ad..15d7cb0 100644
--- a/go/mysql/connection.go
+++ b/go/mysql/connection.go
@@ -18,23 +18,23 @@ import (
 )
 
 const (
-	TLS_CONFIG_KEY       = "ghost"
+	TLS_CONFIG_KEY = "ghost"
 )
 
 // ConnectionConfig is the minimal configuration required to connect to a MySQL server
 type ConnectionConfig struct {
-	Key        InstanceKey
-	User       string
-	Password   string
-	ImpliedKey *InstanceKey
-	tlsConfig  *tls.Config
-	Timeout    float64
+	Key                  InstanceKey
+	User                 string
+	Password             string
+	ImpliedKey           *InstanceKey
+	tlsConfig            *tls.Config
+	Timeout              float64
 	transactionIsolation string
 }
 
 func NewConnectionConfig(transactionIsolation string) *ConnectionConfig {
 	config := &ConnectionConfig{
-		Key: InstanceKey{},
+		Key:                  InstanceKey{},
 		transactionIsolation: transactionIsolation,
 	}
 	config.ImpliedKey = &config.Key
diff --git a/go/mysql/connection_test.go b/go/mysql/connection_test.go
index 2f39c4f..e8cdc27 100644
--- a/go/mysql/connection_test.go
+++ b/go/mysql/connection_test.go
@@ -17,7 +17,6 @@ const (
 	transactionIsolation = "REPEATABLE-READ"
 )
 
-
 func init() {
 	log.SetLevel(log.ERROR)
 }

From da3514253f5cd848c1cbcaad63ad794427ed1833 Mon Sep 17 00:00:00 2001
From: lukelewang <lukelewang@tencent.com>
Date: Sat, 26 Nov 2022 01:38:12 +0800
Subject: [PATCH 23/28] add support for rocksdb

---
 go/base/context.go                  | 11 ++--
 go/cmd/gh-ost/main.go               |  8 +--
 go/mysql/connection.go              | 20 +++----
 go/mysql/connection_test.go         | 17 ++++--
 localtests/test.sh                  | 11 ++--
 script/cibuild-gh-ost-replica-tests | 86 +++++++++++++++--------------
 6 files changed, 83 insertions(+), 70 deletions(-)

diff --git a/go/base/context.go b/go/base/context.go
index b68bf7b..be28ac2 100644
--- a/go/base/context.go
+++ b/go/base/context.go
@@ -270,6 +270,8 @@ func NewMigrationContext() *MigrationContext {
 		Uuid:                                uuid.NewV4().String(),
 		defaultNumRetries:                   60,
 		ChunkSize:                           1000,
+		InspectorConnectionConfig:           mysql.NewConnectionConfig(),
+		ApplierConnectionConfig:             mysql.NewConnectionConfig(),
 		MaxLagMillisecondsThrottleThreshold: 1500,
 		CutOverLockTimeoutSeconds:           3,
 		DMLBatchSize:                        10,
@@ -288,7 +290,7 @@ func NewMigrationContext() *MigrationContext {
 	}
 }
 
-func (this *MigrationContext) SetConnectionConfig(storageEngine string, host string, port int, timeout float64) error {
+func (this *MigrationContext) SetConnectionConfig(storageEngine string) error {
 	transactionIsolation := "REPEATABLE-READ"
 	switch storageEngine {
 	case "rocksdb":
@@ -298,11 +300,8 @@ func (this *MigrationContext) SetConnectionConfig(storageEngine string, host str
 	default:
 		transactionIsolation = "REPEATABLE-READ"
 	}
-	this.InspectorConnectionConfig = mysql.NewConnectionConfig(transactionIsolation)
-	this.InspectorConnectionConfig.Key.Hostname = host
-	this.InspectorConnectionConfig.Key.Port = port
-	this.InspectorConnectionConfig.Timeout = timeout
-	this.ApplierConnectionConfig = mysql.NewConnectionConfig(transactionIsolation)
+	this.InspectorConnectionConfig.TransactionIsolation = transactionIsolation
+	this.ApplierConnectionConfig.TransactionIsolation = transactionIsolation
 	return nil
 }
 
diff --git a/go/cmd/gh-ost/main.go b/go/cmd/gh-ost/main.go
index 145ef65..98310f3 100644
--- a/go/cmd/gh-ost/main.go
+++ b/go/cmd/gh-ost/main.go
@@ -47,10 +47,10 @@ func acceptSignals(migrationContext *base.MigrationContext) {
 // main is the application's entry point. It will either spawn a CLI or HTTP interfaces.
 func main() {
 	migrationContext := base.NewMigrationContext()
-	host := flag.String("host", "127.0.0.1", "MySQL hostname (preferably a replica, not the master)")
-	port := flag.Int("port", 3306, "MySQL port (preferably a replica, not the master)")
-	timeout := flag.Float64("mysql-timeout", 0.0, "Connect, read and write timeout for MySQL")
+	flag.StringVar(&migrationContext.InspectorConnectionConfig.Key.Hostname, "host", "127.0.0.1", "MySQL hostname (preferably a replica, not the master)")
 	flag.StringVar(&migrationContext.AssumeMasterHostname, "assume-master-host", "", "(optional) explicitly tell gh-ost the identity of the master. Format: some.host.com[:port] This is useful in master-master setups where you wish to pick an explicit master, or in a tungsten-replicator where gh-ost is unable to determine the master")
+	flag.IntVar(&migrationContext.InspectorConnectionConfig.Key.Port, "port", 3306, "MySQL port (preferably a replica, not the master)")
+	flag.Float64Var(&migrationContext.InspectorConnectionConfig.Timeout, "mysql-timeout", 0.0, "Connect, read and write timeout for MySQL")
 	flag.StringVar(&migrationContext.CliUser, "user", "", "MySQL user")
 	flag.StringVar(&migrationContext.CliPassword, "password", "", "MySQL password")
 	flag.StringVar(&migrationContext.CliMasterUser, "master-user", "", "MySQL user on master, if different from that on replica. Requires --assume-master-host")
@@ -183,7 +183,7 @@ func main() {
 		migrationContext.Log.SetLevel(log.ERROR)
 	}
 
-	if err := migrationContext.SetConnectionConfig(*storageEngine, *host, *port, *timeout); err != nil {
+	if err := migrationContext.SetConnectionConfig(*storageEngine); err != nil {
 		migrationContext.Log.Fatale(err)
 	}
 
diff --git a/go/mysql/connection.go b/go/mysql/connection.go
index 15d7cb0..6250925 100644
--- a/go/mysql/connection.go
+++ b/go/mysql/connection.go
@@ -29,13 +29,12 @@ type ConnectionConfig struct {
 	ImpliedKey           *InstanceKey
 	tlsConfig            *tls.Config
 	Timeout              float64
-	transactionIsolation string
+	TransactionIsolation string
 }
 
-func NewConnectionConfig(transactionIsolation string) *ConnectionConfig {
+func NewConnectionConfig() *ConnectionConfig {
 	config := &ConnectionConfig{
-		Key:                  InstanceKey{},
-		transactionIsolation: transactionIsolation,
+		Key: InstanceKey{},
 	}
 	config.ImpliedKey = &config.Key
 	return config
@@ -44,11 +43,12 @@ func NewConnectionConfig(transactionIsolation string) *ConnectionConfig {
 // DuplicateCredentials creates a new connection config with given key and with same credentials as this config
 func (this *ConnectionConfig) DuplicateCredentials(key InstanceKey) *ConnectionConfig {
 	config := &ConnectionConfig{
-		Key:       key,
-		User:      this.User,
-		Password:  this.Password,
-		tlsConfig: this.tlsConfig,
-		Timeout:   this.Timeout,
+		Key:                  key,
+		User:                 this.User,
+		Password:             this.Password,
+		tlsConfig:            this.tlsConfig,
+		Timeout:              this.Timeout,
+		TransactionIsolation: this.TransactionIsolation,
 	}
 	config.ImpliedKey = &config.Key
 	return config
@@ -127,7 +127,7 @@ func (this *ConnectionConfig) GetDBUri(databaseName string) string {
 		"charset=utf8mb4,utf8,latin1",
 		"interpolateParams=true",
 		fmt.Sprintf("tls=%s", tlsOption),
-		fmt.Sprintf("transaction_isolation=%q", this.transactionIsolation),
+		fmt.Sprintf("transaction_isolation=%q", this.TransactionIsolation),
 		fmt.Sprintf("timeout=%fs", this.Timeout),
 		fmt.Sprintf("readTimeout=%fs", this.Timeout),
 		fmt.Sprintf("writeTimeout=%fs", this.Timeout),
diff --git a/go/mysql/connection_test.go b/go/mysql/connection_test.go
index e8cdc27..5667235 100644
--- a/go/mysql/connection_test.go
+++ b/go/mysql/connection_test.go
@@ -22,17 +22,18 @@ func init() {
 }
 
 func TestNewConnectionConfig(t *testing.T) {
-	c := NewConnectionConfig(transactionIsolation)
+	c := NewConnectionConfig()
 	test.S(t).ExpectEquals(c.Key.Hostname, "")
 	test.S(t).ExpectEquals(c.Key.Port, 0)
 	test.S(t).ExpectEquals(c.ImpliedKey.Hostname, "")
 	test.S(t).ExpectEquals(c.ImpliedKey.Port, 0)
 	test.S(t).ExpectEquals(c.User, "")
 	test.S(t).ExpectEquals(c.Password, "")
+	test.S(t).ExpectEquals(c.TransactionIsolation, "")
 }
 
 func TestDuplicateCredentials(t *testing.T) {
-	c := NewConnectionConfig(transactionIsolation)
+	c := NewConnectionConfig()
 	c.Key = InstanceKey{Hostname: "myhost", Port: 3306}
 	c.User = "gromit"
 	c.Password = "penguin"
@@ -40,6 +41,7 @@ func TestDuplicateCredentials(t *testing.T) {
 		InsecureSkipVerify: true,
 		ServerName:         "feathers",
 	}
+	c.TransactionIsolation = transactionIsolation
 
 	dup := c.DuplicateCredentials(InstanceKey{Hostname: "otherhost", Port: 3310})
 	test.S(t).ExpectEquals(dup.Key.Hostname, "otherhost")
@@ -49,13 +51,15 @@ func TestDuplicateCredentials(t *testing.T) {
 	test.S(t).ExpectEquals(dup.User, "gromit")
 	test.S(t).ExpectEquals(dup.Password, "penguin")
 	test.S(t).ExpectEquals(dup.tlsConfig, c.tlsConfig)
+	test.S(t).ExpectEquals(dup.TransactionIsolation, c.TransactionIsolation)
 }
 
 func TestDuplicate(t *testing.T) {
-	c := NewConnectionConfig(transactionIsolation)
+	c := NewConnectionConfig()
 	c.Key = InstanceKey{Hostname: "myhost", Port: 3306}
 	c.User = "gromit"
 	c.Password = "penguin"
+	c.TransactionIsolation = transactionIsolation
 
 	dup := c.Duplicate()
 	test.S(t).ExpectEquals(dup.Key.Hostname, "myhost")
@@ -64,26 +68,29 @@ func TestDuplicate(t *testing.T) {
 	test.S(t).ExpectEquals(dup.ImpliedKey.Port, 3306)
 	test.S(t).ExpectEquals(dup.User, "gromit")
 	test.S(t).ExpectEquals(dup.Password, "penguin")
+	test.S(t).ExpectEquals(dup.TransactionIsolation, transactionIsolation)
 }
 
 func TestGetDBUri(t *testing.T) {
-	c := NewConnectionConfig(transactionIsolation)
+	c := NewConnectionConfig()
 	c.Key = InstanceKey{Hostname: "myhost", Port: 3306}
 	c.User = "gromit"
 	c.Password = "penguin"
 	c.Timeout = 1.2345
+	c.TransactionIsolation = transactionIsolation
 
 	uri := c.GetDBUri("test")
 	test.S(t).ExpectEquals(uri, `gromit:penguin@tcp(myhost:3306)/test?autocommit=true&charset=utf8mb4,utf8,latin1&interpolateParams=true&tls=false&transaction_isolation="REPEATABLE-READ"&timeout=1.234500s&readTimeout=1.234500s&writeTimeout=1.234500s`)
 }
 
 func TestGetDBUriWithTLSSetup(t *testing.T) {
-	c := NewConnectionConfig(transactionIsolation)
+	c := NewConnectionConfig()
 	c.Key = InstanceKey{Hostname: "myhost", Port: 3306}
 	c.User = "gromit"
 	c.Password = "penguin"
 	c.Timeout = 1.2345
 	c.tlsConfig = &tls.Config{}
+	c.TransactionIsolation = transactionIsolation
 
 	uri := c.GetDBUri("test")
 	test.S(t).ExpectEquals(uri, `gromit:penguin@tcp(myhost:3306)/test?autocommit=true&charset=utf8mb4,utf8,latin1&interpolateParams=true&tls=ghost&transaction_isolation="REPEATABLE-READ"&timeout=1.234500s&readTimeout=1.234500s&writeTimeout=1.234500s`)
diff --git a/localtests/test.sh b/localtests/test.sh
index d73dab2..14ecd83 100755
--- a/localtests/test.sh
+++ b/localtests/test.sh
@@ -11,6 +11,7 @@ tests_path=$(dirname $0)
 test_logfile=/tmp/gh-ost-test.log
 default_ghost_binary=/tmp/gh-ost-test
 ghost_binary=""
+storage_engine=innodb
 exec_command_file=/tmp/gh-ost-test.bash
 ghost_structure_output_file=/tmp/gh-ost-test.ghost.structure.sql
 orig_content_output_file=/tmp/gh-ost-test.orig.content.csv
@@ -24,12 +25,13 @@ replica_port=
 original_sql_mode=
 
 OPTIND=1
-while getopts "b:" OPTION
+while getopts "b:s:" OPTION
 do
   case $OPTION in
     b)
-      ghost_binary="$OPTARG"
-    ;;
+      ghost_binary="$OPTARG";;
+    s)
+      storage_engine="$OPTARG";;
   esac
 done
 shift $((OPTIND-1))
@@ -158,7 +160,8 @@ test_single() {
     --assume-master-host=${master_host}:${master_port}
     --database=test \
     --table=gh_ost_test \
-    --alter='engine=innodb' \
+    --storage-engine=${storage_engine} \
+    --alter='engine=${storage_engine}' \
     --exact-rowcount \
     --assume-rbr \
     --initially-drop-old-table \
diff --git a/script/cibuild-gh-ost-replica-tests b/script/cibuild-gh-ost-replica-tests
index bb60d71..31b3139 100755
--- a/script/cibuild-gh-ost-replica-tests
+++ b/script/cibuild-gh-ost-replica-tests
@@ -36,8 +36,16 @@ test_mysql_version() {
 
   mkdir -p sandbox/binary
   rm -rf sandbox/binary/*
-  gh-ost-ci-env/bin/linux/dbdeployer unpack gh-ost-ci-env/mysql-tarballs/"$mysql_version".tar.xz --sandbox-binary ${PWD}/sandbox/binary
-
+  local mysql_server=${mysql_version%-*}
+  if echo "$mysql_server" | egrep -i "percona" ; then
+    tarball_name=Percona-Server-${mysql_version#*-}-12-Linux.x86_64.glibc2.12-minimal.tar.gz
+    rm -f gh-ost-ci-env/mysql-tarballs/${tarball_name}
+    ln -s "$mysql_version".tar.xz gh-ost-ci-env/mysql-tarballs/${tarball_name}
+    gh-ost-ci-env/bin/linux/dbdeployer unpack gh-ost-ci-env/mysql-tarballs/${tarball_name} --sandbox-binary ${PWD}/sandbox/binary
+    rm -f gh-ost-ci-env/mysql-tarballs/${tarball_name}
+  else
+    gh-ost-ci-env/bin/linux/dbdeployer unpack gh-ost-ci-env/mysql-tarballs/"$mysql_version".tar.xz --sandbox-binary ${PWD}/sandbox/binary
+  fi
   mkdir -p sandboxes
   rm -rf sandboxes/*
 
@@ -60,49 +68,45 @@ test_mysql_version() {
   gh-ost-test-mysql-master -uroot -e "create user 'gh-ost'@'%' identified by 'gh-ost'"
   gh-ost-test-mysql-master -uroot -e "grant all on *.* to 'gh-ost'@'%'"
 
-  local mysql_server=${mysql_version%-*}
   if echo "$mysql_server" | egrep -i "percona" ; then
     echo "### Preparing for rocksdb in PerconaServer"
-    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_CFSTATS SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_DBSTATS SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_PERF_CONTEXT SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_PERF_CONTEXT_GLOBAL SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_CF_OPTIONS SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_GLOBAL_INFO SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_COMPACTION_HISTORY SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_COMPACTION_STATS SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_ACTIVE_COMPACTION_STATS SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_DDL SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_INDEX_FILE_MAP SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_LOCKS SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_TRX SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-master -uroot -e "INSTALL PLUGIN ROCKSDB_DEADLOCK SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-master -uroot -e "set global default_storage_engine='ROCKSDB'"
-    gh-ost-test-mysql-master -uroot -e "set global transaction_isolation='READ-COMMITTED'"
+    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_CFSTATS SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_DBSTATS SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_PERF_CONTEXT SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_PERF_CONTEXT_GLOBAL SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_CF_OPTIONS SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_GLOBAL_INFO SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_COMPACTION_STATS SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_DDL SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_INDEX_FILE_MAP SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_LOCKS SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_TRX SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_DEADLOCK SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-master -uroot -e 'set global default_storage_engine="ROCKSDB"'
+    gh-ost-test-mysql-master -uroot -e 'set global transaction_isolation="READ-COMMITTED"'
+    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_CFSTATS SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_DBSTATS SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_PERF_CONTEXT SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_PERF_CONTEXT_GLOBAL SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_CF_OPTIONS SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_GLOBAL_INFO SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_COMPACTION_STATS SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_DDL SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_INDEX_FILE_MAP SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_LOCKS SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_TRX SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_DEADLOCK SONAME "ha_rocksdb.so"'
+    gh-ost-test-mysql-replica -uroot -e 'set global default_storage_engine="ROCKSDB"'
+    gh-ost-test-mysql-replica -uroot -e 'set global transaction_isolation="READ-COMMITTED"'
 
-    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_CFSTATS SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_DBSTATS SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_PERF_CONTEXT SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_PERF_CONTEXT_GLOBAL SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_CF_OPTIONS SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_GLOBAL_INFO SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_COMPACTION_HISTORY SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_COMPACTION_STATS SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_ACTIVE_COMPACTION_STATS SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_DDL SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_INDEX_FILE_MAP SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_LOCKS SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_TRX SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-replica -uroot -e "INSTALL PLUGIN ROCKSDB_DEADLOCK SONAME 'ha_rocksdb.so'"
-    gh-ost-test-mysql-replica -uroot -e "set global default_storage_engine='ROCKSDB'"
-    gh-ost-test-mysql-replica -uroot -e "set global transaction_isolation='READ-COMMITTED'"
+    echo "### Running gh-ost tests for $mysql_version"
+    ./localtests/test.sh -b bin/gh-ost -s rocksdb
+  else
+    echo "### Running gh-ost tests for $mysql_version"
+    ./localtests/test.sh -b bin/gh-ost -s innodb
   fi
-
-  echo "### Running gh-ost tests for $mysql_version"
-  ./localtests/test.sh -b bin/gh-ost
-
   find sandboxes -name "stop_all" | bash
 }
 

From af1e0d647f661e00b05b7701d36b025d535e6e01 Mon Sep 17 00:00:00 2001
From: lukelewang <lukelewang@tencent.com>
Date: Sat, 26 Nov 2022 01:43:11 +0800
Subject: [PATCH 24/28] add support for rocksdb

---
 go/base/context.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/go/base/context.go b/go/base/context.go
index be28ac2..764a3e6 100644
--- a/go/base/context.go
+++ b/go/base/context.go
@@ -291,7 +291,7 @@ func NewMigrationContext() *MigrationContext {
 }
 
 func (this *MigrationContext) SetConnectionConfig(storageEngine string) error {
-	transactionIsolation := "REPEATABLE-READ"
+	var transactionIsolation string
 	switch storageEngine {
 	case "rocksdb":
 		transactionIsolation = "READ-COMMITTED"

From ed71099ce667e833533d95b883567babc5166473 Mon Sep 17 00:00:00 2001
From: lukelewang <lukelewang@tencent.com>
Date: Sat, 26 Nov 2022 13:08:19 +0800
Subject: [PATCH 25/28] add percona to versions in workflows

---
 .github/workflows/replica-tests.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/replica-tests.yml b/.github/workflows/replica-tests.yml
index 0a82f00..f2a52ec 100644
--- a/.github/workflows/replica-tests.yml
+++ b/.github/workflows/replica-tests.yml
@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-20.04
     strategy:
       matrix:
-        version: [mysql-5.7.25,mysql-8.0.16]
+        version: [mysql-5.7.25,mysql-8.0.16,PerconaServer-8.0.21]
 
     steps:
     - uses: actions/checkout@v2

From 6e2be1d44fb5e19e4c6ecf044b220810b0c77927 Mon Sep 17 00:00:00 2001
From: lukelewang <lukelewang@tencent.com>
Date: Sun, 27 Nov 2022 13:54:01 +0800
Subject: [PATCH 26/28] add description and optimize tests

---
 doc/command-line-flags.md           | 11 ++++++++++-
 go/base/context.go                  |  2 --
 go/cmd/gh-ost/main.go               |  3 +++
 script/cibuild-gh-ost-replica-tests | 24 ------------------------
 4 files changed, 13 insertions(+), 27 deletions(-)

diff --git a/doc/command-line-flags.md b/doc/command-line-flags.md
index 5a61631..82cb884 100644
--- a/doc/command-line-flags.md
+++ b/doc/command-line-flags.md
@@ -247,7 +247,16 @@ Allows `gh-ost` to connect to the MySQL servers using encrypted connections, but
 `--ssl-key=/path/to/ssl-key.key`: SSL private key file (in PEM format).
 
 ### storage-engine
-default is `innodb`. When set to `rocksdb`, some necessary changes (e.g. sets isolation level to READ_COMMITTED) is made to support rocksdb as transactional engine. 
+default is `innodb`, and `rocksdb`as an optional. InnoDB and RocksDB are both transactional engines, supporting both shared and exclusive row locks.
+
+But RocksDB currently lacks a few features support compared to InnoDB:
+- Gap Locks
+- Foreign Key
+- Generated Columns
+- Spatial
+- Geometry
+
+When `--storage-engine=rocksdb`, `gh-ost` will make some changes necessary (e.g. sets isolation level to `READ_COMMITTED`) to support RocksDB.
 
 ### test-on-replica
 
diff --git a/go/base/context.go b/go/base/context.go
index 764a3e6..e3472f5 100644
--- a/go/base/context.go
+++ b/go/base/context.go
@@ -295,8 +295,6 @@ func (this *MigrationContext) SetConnectionConfig(storageEngine string) error {
 	switch storageEngine {
 	case "rocksdb":
 		transactionIsolation = "READ-COMMITTED"
-	case "innodb":
-		transactionIsolation = "REPEATABLE-READ"
 	default:
 		transactionIsolation = "REPEATABLE-READ"
 	}
diff --git a/go/cmd/gh-ost/main.go b/go/cmd/gh-ost/main.go
index 98310f3..e214306 100644
--- a/go/cmd/gh-ost/main.go
+++ b/go/cmd/gh-ost/main.go
@@ -252,6 +252,9 @@ func main() {
 	if *replicationLagQuery != "" {
 		migrationContext.Log.Warning("--replication-lag-query is deprecated")
 	}
+	if *storageEngine == "rocksdb" {
+		migrationContext.Log.Warning("RocksDB storage engine support is experimental")
+	}
 
 	switch *cutOver {
 	case "atomic", "default", "":
diff --git a/script/cibuild-gh-ost-replica-tests b/script/cibuild-gh-ost-replica-tests
index 31b3139..90eb856 100755
--- a/script/cibuild-gh-ost-replica-tests
+++ b/script/cibuild-gh-ost-replica-tests
@@ -71,33 +71,9 @@ test_mysql_version() {
   if echo "$mysql_server" | egrep -i "percona" ; then
     echo "### Preparing for rocksdb in PerconaServer"
     gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_CFSTATS SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_DBSTATS SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_PERF_CONTEXT SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_PERF_CONTEXT_GLOBAL SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_CF_OPTIONS SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_GLOBAL_INFO SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_COMPACTION_STATS SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_DDL SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_INDEX_FILE_MAP SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_LOCKS SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_TRX SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-master -uroot -e 'INSTALL PLUGIN ROCKSDB_DEADLOCK SONAME "ha_rocksdb.so"'
     gh-ost-test-mysql-master -uroot -e 'set global default_storage_engine="ROCKSDB"'
     gh-ost-test-mysql-master -uroot -e 'set global transaction_isolation="READ-COMMITTED"'
     gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_CFSTATS SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_DBSTATS SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_PERF_CONTEXT SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_PERF_CONTEXT_GLOBAL SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_CF_OPTIONS SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_GLOBAL_INFO SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_COMPACTION_STATS SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_DDL SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_INDEX_FILE_MAP SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_LOCKS SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_TRX SONAME "ha_rocksdb.so"'
-    gh-ost-test-mysql-replica -uroot -e 'INSTALL PLUGIN ROCKSDB_DEADLOCK SONAME "ha_rocksdb.so"'
     gh-ost-test-mysql-replica -uroot -e 'set global default_storage_engine="ROCKSDB"'
     gh-ost-test-mysql-replica -uroot -e 'set global transaction_isolation="READ-COMMITTED"'
 

From 9f3cf74444823a53dc2d1a99c6c561a5a8b8abc1 Mon Sep 17 00:00:00 2001
From: wangzihuacool <47876169+wangzihuacool@users.noreply.github.com>
Date: Tue, 29 Nov 2022 10:16:58 +0800
Subject: [PATCH 27/28] Apply suggestions from code review

Co-authored-by: dm-2 <45519614+dm-2@users.noreply.github.com>
---
 doc/command-line-flags.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/command-line-flags.md b/doc/command-line-flags.md
index 82cb884..021462f 100644
--- a/doc/command-line-flags.md
+++ b/doc/command-line-flags.md
@@ -247,7 +247,7 @@ Allows `gh-ost` to connect to the MySQL servers using encrypted connections, but
 `--ssl-key=/path/to/ssl-key.key`: SSL private key file (in PEM format).
 
 ### storage-engine
-default is `innodb`, and `rocksdb`as an optional. InnoDB and RocksDB are both transactional engines, supporting both shared and exclusive row locks.
+Default is `innodb`, and `rocksdb` support is currently experimental. InnoDB and RocksDB are both transactional engines, supporting both shared and exclusive row locks.
 
 But RocksDB currently lacks a few features support compared to InnoDB:
 - Gap Locks

From 20af3af283d88ec3825cc99e140d28411ae7418a Mon Sep 17 00:00:00 2001
From: wangzihuacool <47876169+wangzihuacool@users.noreply.github.com>
Date: Tue, 29 Nov 2022 10:30:01 +0800
Subject: [PATCH 28/28] Apply suggestions from code review

Co-authored-by: Tim Vaillancourt <tim@timvaillancourt.com>
---
 go/cmd/gh-ost/main.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/go/cmd/gh-ost/main.go b/go/cmd/gh-ost/main.go
index e214306..3daf244 100644
--- a/go/cmd/gh-ost/main.go
+++ b/go/cmd/gh-ost/main.go
@@ -68,7 +68,7 @@ func main() {
 	flag.StringVar(&migrationContext.OriginalTableName, "table", "", "table name (mandatory)")
 	flag.StringVar(&migrationContext.AlterStatement, "alter", "", "alter statement (mandatory)")
 	flag.BoolVar(&migrationContext.AttemptInstantDDL, "attempt-instant-ddl", false, "Attempt to use instant DDL for this migration first")
-	storageEngine := flag.String("storage-engine", "innodb", "Specify table storage engine (default: 'innodb'). When 'rocksdb': change session transaction isolation level to READ_COMMITTED.")
+	storageEngine := flag.String("storage-engine", "innodb", "Specify table storage engine (default: 'innodb'). When 'rocksdb': the session transaction isolation level is changed from REPEATABLE_READ to READ_COMMITTED.")
 
 	flag.BoolVar(&migrationContext.CountTableRows, "exact-rowcount", false, "actually count table rows as opposed to estimate them (results in more accurate progress estimation)")
 	flag.BoolVar(&migrationContext.ConcurrentCountTableRows, "concurrent-rowcount", true, "(with --exact-rowcount), when true (default): count rows after row-copy begins, concurrently, and adjust row estimate later on; when false: first count rows, then start row copy")