Make --slave-parallel-workers an alias for --slave-parallel-threads

This is to add compatibility with the similar MySQL option.

mysql-test/r/mysqld--help.result

@@ -974,6 +974,8 @@ The following options may be given as the first argument:
  replication domains. Note that these threads are in
  addition to the IO and SQL threads, which are always
  created by a replication slave
+ --slave-parallel-workers=# 
+ Alias for slave_parallel_threads
  --slave-run-triggers-for-rbr=name 
  Modes for how triggers in row-base replication on slave
  side will be executed. Legal values are NO (default), YES
@@ -1400,6 +1402,7 @@ slave-net-timeout 3600
 slave-parallel-max-queued 131072
 slave-parallel-mode conservative
 slave-parallel-threads 0
+slave-parallel-workers 0
 slave-run-triggers-for-rbr NO
 slave-skip-errors (No default value)
 slave-sql-verify-checksum TRUE

mysql-test/suite/sys_vars/r/sysvars_server_notembedded,32bit.rdiff

@@ -1134,7 +1134,16 @@
  VARIABLE_COMMENT	If non-zero, number of threads to spawn to apply in parallel events on the slave that were group-committed on the master or were logged with GTID in different replication domains. Note that these threads are in addition to the IO and SQL threads, which are always created by a replication slave
  NUMERIC_MIN_VALUE	0
  NUMERIC_MAX_VALUE	16383
-@@ -4019,7 +4019,7 @@
+@@ -3977,7 +3977,7 @@
+ GLOBAL_VALUE_ORIGIN	COMPILE-TIME
+ DEFAULT_VALUE	0
+ VARIABLE_SCOPE	GLOBAL
+-VARIABLE_TYPE	BIGINT UNSIGNED
++VARIABLE_TYPE	INT UNSIGNED
+ VARIABLE_COMMENT	Alias for slave_parallel_threads
+ NUMERIC_MIN_VALUE	0
+ NUMERIC_MAX_VALUE	16383
+@@ -4033,7 +4033,7 @@
  GLOBAL_VALUE_ORIGIN	COMPILE-TIME
  DEFAULT_VALUE	10
  VARIABLE_SCOPE	GLOBAL
@@ -1143,7 +1152,7 @@
  VARIABLE_COMMENT	Number of times the slave SQL thread will retry a transaction in case it failed with a deadlock or elapsed lock wait timeout, before giving up and stopping
  NUMERIC_MIN_VALUE	0
  NUMERIC_MAX_VALUE	4294967295
-@@ -4047,7 +4047,7 @@
+@@ -4061,7 +4061,7 @@
  GLOBAL_VALUE_ORIGIN	COMPILE-TIME
  DEFAULT_VALUE	2
  VARIABLE_SCOPE	GLOBAL
@@ -1152,7 +1161,7 @@
  VARIABLE_COMMENT	If creating the thread takes longer than this value (in seconds), the Slow_launch_threads counter will be incremented
  NUMERIC_MIN_VALUE	0
  NUMERIC_MAX_VALUE	31536000
-@@ -4106,7 +4106,7 @@
+@@ -4120,7 +4120,7 @@
  VARIABLE_TYPE	BIGINT UNSIGNED
  VARIABLE_COMMENT	Each thread that needs to do a sort allocates a buffer of this size
  NUMERIC_MIN_VALUE	1024
@@ -1161,7 +1170,7 @@
  NUMERIC_BLOCK_SIZE	1
  ENUM_VALUE_LIST	NULL
  READ_ONLY	NO
-@@ -4397,7 +4397,7 @@
+@@ -4411,7 +4411,7 @@
  GLOBAL_VALUE_ORIGIN	COMPILE-TIME
  DEFAULT_VALUE	256
  VARIABLE_SCOPE	GLOBAL
@@ -1170,7 +1179,7 @@
  VARIABLE_COMMENT	The soft upper limit for number of cached stored routines for one connection.
  NUMERIC_MIN_VALUE	0
  NUMERIC_MAX_VALUE	524288
-@@ -4495,7 +4495,7 @@
+@@ -4509,7 +4509,7 @@
  GLOBAL_VALUE_ORIGIN	AUTO
  DEFAULT_VALUE	400
  VARIABLE_SCOPE	GLOBAL
@@ -1179,7 +1188,7 @@
  VARIABLE_COMMENT	The number of cached table definitions
  NUMERIC_MIN_VALUE	400
  NUMERIC_MAX_VALUE	524288
-@@ -4509,7 +4509,7 @@
+@@ -4523,7 +4523,7 @@
  GLOBAL_VALUE_ORIGIN	COMPILE-TIME
  DEFAULT_VALUE	2000
  VARIABLE_SCOPE	GLOBAL
@@ -1188,7 +1197,7 @@
  VARIABLE_COMMENT	The number of cached open tables
  NUMERIC_MIN_VALUE	1
  NUMERIC_MAX_VALUE	524288
-@@ -4523,7 +4523,7 @@
+@@ -4537,7 +4537,7 @@
  GLOBAL_VALUE_ORIGIN	COMPILE-TIME
  DEFAULT_VALUE	0
  VARIABLE_SCOPE	GLOBAL
@@ -1197,7 +1206,7 @@
  VARIABLE_COMMENT	How many threads we should keep in a cache for reuse
  NUMERIC_MIN_VALUE	0
  NUMERIC_MAX_VALUE	16384
-@@ -4537,7 +4537,7 @@
+@@ -4551,7 +4551,7 @@
  GLOBAL_VALUE_ORIGIN	COMPILE-TIME
  DEFAULT_VALUE	10
  VARIABLE_SCOPE	GLOBAL
@@ -1206,7 +1215,7 @@
  VARIABLE_COMMENT	Permits the application to give the threads system a hint for the desired number of threads that should be run at the same time.This variable has no effect, and is deprecated. It will be removed in a future release.
  NUMERIC_MIN_VALUE	1
  NUMERIC_MAX_VALUE	512
-@@ -4722,7 +4722,7 @@
+@@ -4736,7 +4736,7 @@
  VARIABLE_TYPE	BIGINT UNSIGNED
  VARIABLE_COMMENT	If an internal in-memory temporary table exceeds this size, MySQL will automatically convert it to an on-disk MyISAM or Aria table
  NUMERIC_MIN_VALUE	1024
@@ -1215,7 +1224,7 @@
  NUMERIC_BLOCK_SIZE	1
  ENUM_VALUE_LIST	NULL
  READ_ONLY	NO
-@@ -4733,7 +4733,7 @@
+@@ -4747,7 +4747,7 @@
  GLOBAL_VALUE_ORIGIN	COMPILE-TIME
  DEFAULT_VALUE	8192
  VARIABLE_SCOPE	SESSION
@@ -1224,7 +1233,7 @@
  VARIABLE_COMMENT	Allocation block size for transactions to be stored in binary log
  NUMERIC_MIN_VALUE	1024
  NUMERIC_MAX_VALUE	134217728
-@@ -4747,7 +4747,7 @@
+@@ -4761,7 +4761,7 @@
  GLOBAL_VALUE_ORIGIN	COMPILE-TIME
  DEFAULT_VALUE	4096
  VARIABLE_SCOPE	SESSION
@@ -1233,7 +1242,7 @@
  VARIABLE_COMMENT	Persistent buffer for transactions to be stored in binary log
  NUMERIC_MIN_VALUE	1024
  NUMERIC_MAX_VALUE	134217728
-@@ -4845,7 +4845,7 @@
+@@ -4859,7 +4859,7 @@
  GLOBAL_VALUE_ORIGIN	COMPILE-TIME
  DEFAULT_VALUE	28800
  VARIABLE_SCOPE	SESSION
@@ -1242,7 +1251,7 @@
  VARIABLE_COMMENT	The number of seconds the server waits for activity on a connection before closing it
  NUMERIC_MIN_VALUE	1
  NUMERIC_MAX_VALUE	31536000
-@@ -4949,7 +4949,7 @@
+@@ -4963,7 +4963,7 @@
  COMMAND_LINE_ARGUMENT	OPTIONAL
  VARIABLE_NAME	OPEN_FILES_LIMIT
  VARIABLE_SCOPE	GLOBAL
@@ -1251,7 +1260,7 @@
  VARIABLE_COMMENT	If this is not 0, then mysqld will use this value to reserve file descriptors to use with setrlimit(). If this value is 0 then mysqld will reserve max_connections*5 or max_connections + table_cache*2 (whichever is larger) number of file descriptors
  NUMERIC_MIN_VALUE	0
  NUMERIC_MAX_VALUE	4294967295
-@@ -4962,7 +4962,7 @@
+@@ -4976,7 +4976,7 @@
  VARIABLE_TYPE	BIGINT UNSIGNED
  VARIABLE_COMMENT	Sets the internal state of the RAND() generator for replication purposes
  NUMERIC_MIN_VALUE	0
@@ -1260,7 +1269,7 @@
  NUMERIC_BLOCK_SIZE	1
  ENUM_VALUE_LIST	NULL
  READ_ONLY	NO
-@@ -4972,7 +4972,7 @@
+@@ -4986,7 +4986,7 @@
  VARIABLE_TYPE	BIGINT UNSIGNED
  VARIABLE_COMMENT	Sets the internal state of the RAND() generator for replication purposes
  NUMERIC_MIN_VALUE	0
@@ -1269,7 +1278,7 @@
  NUMERIC_BLOCK_SIZE	1
  ENUM_VALUE_LIST	NULL
  READ_ONLY	NO
-@@ -5057,7 +5057,7 @@
+@@ -5071,7 +5071,7 @@
  VARIABLE_NAME	LOG_TC_SIZE
  GLOBAL_VALUE_ORIGIN	AUTO
  VARIABLE_SCOPE	GLOBAL

mysql-test/suite/sys_vars/r/sysvars_server_notembedded.result

@@ -3971,6 +3971,20 @@ NUMERIC_BLOCK_SIZE	1
 ENUM_VALUE_LIST	NULL
 READ_ONLY	NO
 COMMAND_LINE_ARGUMENT	REQUIRED
+VARIABLE_NAME	SLAVE_PARALLEL_WORKERS
+SESSION_VALUE	NULL
+GLOBAL_VALUE	0
+GLOBAL_VALUE_ORIGIN	COMPILE-TIME
+DEFAULT_VALUE	0
+VARIABLE_SCOPE	GLOBAL
+VARIABLE_TYPE	BIGINT UNSIGNED
+VARIABLE_COMMENT	Alias for slave_parallel_threads
+NUMERIC_MIN_VALUE	0
+NUMERIC_MAX_VALUE	16383
+NUMERIC_BLOCK_SIZE	1
+ENUM_VALUE_LIST	NULL
+READ_ONLY	NO
+COMMAND_LINE_ARGUMENT	REQUIRED
 VARIABLE_NAME	SLAVE_RUN_TRIGGERS_FOR_RBR
 SESSION_VALUE	NULL
 GLOBAL_VALUE	NO

sql/mysqld.cc

@@ -7694,7 +7694,6 @@ struct my_option my_long_options[]=
   MYSQL_TO_BE_IMPLEMENTED_OPTION("slave-allow-batching"),         // HAVE_REPLICATION
   MYSQL_COMPATIBILITY_OPTION("slave-checkpoint-period"),      // HAVE_REPLICATION
   MYSQL_COMPATIBILITY_OPTION("slave-checkpoint-group"),       // HAVE_REPLICATION
-  MYSQL_SUGGEST_ANALOG_OPTION("slave-parallel-workers", "--slave-parallel-threads"),       // HAVE_REPLICATION
   MYSQL_SUGGEST_ANALOG_OPTION("slave-pending-jobs-size-max", "--slave-parallel-max-queued"),  // HAVE_REPLICATION
   MYSQL_TO_BE_IMPLEMENTED_OPTION("disconnect-on-expired-password"),
   MYSQL_TO_BE_IMPLEMENTED_OPTION("sha256-password-private-key-path"), // HAVE_OPENSSL && !HAVE_YASSL

sql/sys_vars.cc

@@ -1848,6 +1848,15 @@ static Sys_var_ulong Sys_slave_parallel_threads(
        NOT_IN_BINLOG, ON_CHECK(check_slave_parallel_threads),
        ON_UPDATE(fix_slave_parallel_threads));
 
+/* Alias for @@slave_parallel_threads to match what MySQL 5.7 uses. */
+static Sys_var_ulong Sys_slave_parallel_workers(
+       "slave_parallel_workers",
+       "Alias for slave_parallel_threads",
+       GLOBAL_VAR(opt_slave_parallel_threads), CMD_LINE(REQUIRED_ARG),
+       VALID_RANGE(0,16383), DEFAULT(0), BLOCK_SIZE(1), NO_MUTEX_GUARD,
+       NOT_IN_BINLOG, ON_CHECK(check_slave_parallel_threads),
+       ON_UPDATE(fix_slave_parallel_threads));
+
 
 static bool
 check_slave_domain_parallel_threads(sys_var *self, THD *thd, set_var *var)