New conf option for SO_SNDBUF in dump thread.

Summary:
A new configuration option rpl_send_buffer_size is added
to control the TCP send buffer size of the socket used in dump thread.

Reference patch: facebook@ac90867

Differential Revision: D6377432 (facebook@a107c9c)

fbshipit-source-id: d9b0099277c

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

@@ -1174,6 +1174,9 @@ The following options may be given as the first argument:
  must be a multiple of 4kb. Making it larger might help
  with IO stalls while reading these files when they are
  not in the OS buffer cache
+ --rpl-send-buffer-size=# 
+ The size of output buffer for the socket used during
+ sending events to a slave.
  --rpl-stop-slave-timeout=# 
  Timeout in seconds to wait for slave to stop before
  returning a warning.
@@ -1772,6 +1775,7 @@ report-port 0
 report-user (No default value)
 require-secure-transport FALSE
 rpl-read-size 8192
+rpl-send-buffer-size 2097152
 rpl-stop-slave-timeout 31536000
 safe-user-create FALSE
 schema-definition-cache 256

mysql-test/suite/binlog_nogtid/r/binlog_persist_only_variables.result

@@ -106,6 +106,7 @@ SET PERSIST_ONLY rpl_semi_sync_master_wait_no_slave = @@GLOBAL.rpl_semi_sync_mas
 SET PERSIST_ONLY rpl_semi_sync_master_wait_point = @@GLOBAL.rpl_semi_sync_master_wait_point;
 SET PERSIST_ONLY rpl_semi_sync_slave_enabled = @@GLOBAL.rpl_semi_sync_slave_enabled;
 SET PERSIST_ONLY rpl_semi_sync_slave_trace_level = @@GLOBAL.rpl_semi_sync_slave_trace_level;
+SET PERSIST_ONLY rpl_send_buffer_size = @@GLOBAL.rpl_send_buffer_size;
 SET PERSIST_ONLY rpl_stop_slave_timeout = @@GLOBAL.rpl_stop_slave_timeout;
 SET PERSIST_ONLY session_track_gtids = @@GLOBAL.session_track_gtids;
 SET PERSIST_ONLY slave_allow_batching = @@GLOBAL.slave_allow_batching;
@@ -220,6 +221,7 @@ RESET PERSIST rpl_semi_sync_master_wait_no_slave;
 RESET PERSIST rpl_semi_sync_master_wait_point;
 RESET PERSIST rpl_semi_sync_slave_enabled;
 RESET PERSIST rpl_semi_sync_slave_trace_level;
+RESET PERSIST rpl_send_buffer_size;
 RESET PERSIST rpl_stop_slave_timeout;
 RESET PERSIST session_track_gtids;
 RESET PERSIST slave_allow_batching;

mysql-test/suite/binlog_nogtid/r/binlog_persist_variables.result

@@ -112,6 +112,7 @@ SET PERSIST rpl_semi_sync_master_wait_no_slave = @@GLOBAL.rpl_semi_sync_master_w
 SET PERSIST rpl_semi_sync_master_wait_point = @@GLOBAL.rpl_semi_sync_master_wait_point;
 SET PERSIST rpl_semi_sync_slave_enabled = @@GLOBAL.rpl_semi_sync_slave_enabled;
 SET PERSIST rpl_semi_sync_slave_trace_level = @@GLOBAL.rpl_semi_sync_slave_trace_level;
+SET PERSIST rpl_send_buffer_size = @@GLOBAL.rpl_send_buffer_size;
 SET PERSIST rpl_stop_slave_timeout = @@GLOBAL.rpl_stop_slave_timeout;
 SET PERSIST session_track_gtids = @@GLOBAL.session_track_gtids;
 SET PERSIST slave_allow_batching = @@GLOBAL.slave_allow_batching;
@@ -249,6 +250,7 @@ RESET PERSIST IF EXISTS rpl_semi_sync_master_wait_no_slave;
 RESET PERSIST IF EXISTS rpl_semi_sync_master_wait_point;
 RESET PERSIST IF EXISTS rpl_semi_sync_slave_enabled;
 RESET PERSIST IF EXISTS rpl_semi_sync_slave_trace_level;
+RESET PERSIST IF EXISTS rpl_send_buffer_size;
 RESET PERSIST IF EXISTS rpl_stop_slave_timeout;
 RESET PERSIST IF EXISTS session_track_gtids;
 RESET PERSIST IF EXISTS slave_allow_batching;

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

@@ -0,0 +1,106 @@
+SET @start_rpl_send_buffer_size = @@global.rpl_send_buffer_size;
+SELECT @start_rpl_send_buffer_size;
+@start_rpl_send_buffer_size
+2097152
+'#--------------------TEST_01------------------------#'
+SET @@global.rpl_send_buffer_size = 20 * 1024;
+SET @@global.rpl_send_buffer_size = DEFAULT;
+SELECT @@global.rpl_send_buffer_size;
+@@global.rpl_send_buffer_size
+2097152
+'#---------------------TEST_02-------------------------#'
+SET @@global.rpl_send_buffer_size = @start_rpl_send_buffer_size;
+SELECT @@global.rpl_send_buffer_size = 2 * 1024 * 1024;
+@@global.rpl_send_buffer_size = 2 * 1024 * 1024
+1
+'#--------------------TEST_03------------------------#'
+SET @@global.rpl_send_buffer_size = 16 * 1024;
+SELECT @@global.rpl_send_buffer_size;
+@@global.rpl_send_buffer_size
+16384
+SET @@global.rpl_send_buffer_size = 128 * 1024 * 1024;
+SELECT @@global.rpl_send_buffer_size;
+@@global.rpl_send_buffer_size
+134217728
+SET @@global.rpl_send_buffer_size = 300 * 1024;
+SELECT @@global.rpl_send_buffer_size;
+@@global.rpl_send_buffer_size
+307200
+SET @@global.rpl_send_buffer_size = 100 * 1024 * 1024;
+SELECT @@global.rpl_send_buffer_size;
+@@global.rpl_send_buffer_size
+104857600
+'#--------------------TEST_04-------------------------#'
+SET @@global.rpl_send_buffer_size = -1;
+Warnings:
+Warning	1292	Truncated incorrect rpl_send_buffer_size value: '-1'
+SELECT @@global.rpl_send_buffer_size;
+@@global.rpl_send_buffer_size
+1024
+SET @@global.rpl_send_buffer_size = 100;
+Warnings:
+Warning	1292	Truncated incorrect rpl_send_buffer_size value: '100'
+SELECT @@global.rpl_send_buffer_size;
+@@global.rpl_send_buffer_size
+1024
+SET @@global.rpl_send_buffer_size = 18446744073709551616;
+ERROR 42000: Incorrect argument type to variable 'rpl_send_buffer_size'
+SELECT @@global.rpl_send_buffer_size;
+@@global.rpl_send_buffer_size
+1024
+SET @@global.rpl_send_buffer_size = 10000.01;
+ERROR 42000: Incorrect argument type to variable 'rpl_send_buffer_size'
+SELECT @@global.rpl_send_buffer_size;
+@@global.rpl_send_buffer_size
+1024
+SET @@global.rpl_send_buffer_size = ON;
+ERROR 42000: Incorrect argument type to variable 'rpl_send_buffer_size'
+SELECT @@global.rpl_send_buffer_size;
+@@global.rpl_send_buffer_size
+1024
+SET @@global.rpl_send_buffer_size = 'test';
+ERROR 42000: Incorrect argument type to variable 'rpl_send_buffer_size'
+SELECT @@global.rpl_send_buffer_size;
+@@global.rpl_send_buffer_size
+1024
+'#-------------------TEST_05----------------------------#'
+SET @@session.rpl_send_buffer_size = 20 * 1024;
+ERROR HY000: Variable 'rpl_send_buffer_size' is a GLOBAL variable and should be set with SET GLOBAL
+SELECT @@session.rpl_send_buffer_size;
+ERROR HY000: Variable 'rpl_send_buffer_size' is a GLOBAL variable
+'#----------------------TEST_06------------------------#'
+SELECT @@global.rpl_send_buffer_size = VARIABLE_VALUE
+FROM performance_schema.global_variables
+WHERE VARIABLE_NAME='rpl_send_buffer_size';
+@@global.rpl_send_buffer_size = VARIABLE_VALUE
+1
+SELECT @@rpl_send_buffer_size = VARIABLE_VALUE
+FROM performance_schema.session_variables
+WHERE VARIABLE_NAME='rpl_send_buffer_size';
+@@rpl_send_buffer_size = VARIABLE_VALUE
+1
+'#---------------------TEST_08----------------------#'
+SET @@global.rpl_send_buffer_size = 30 * 1024;
+SELECT @@rpl_send_buffer_size = @@global.rpl_send_buffer_size;
+@@rpl_send_buffer_size = @@global.rpl_send_buffer_size
+1
+'#---------------------TEST_09----------------------#'
+SET rpl_send_buffer_size = 20 * 1024;
+ERROR HY000: Variable 'rpl_send_buffer_size' is a GLOBAL variable and should be set with SET GLOBAL
+SELECT @@rpl_send_buffer_size;
+@@rpl_send_buffer_size
+30720
+SET local.rpl_send_buffer_size = 20 * 1024;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'local.rpl_send_buffer_size = 20 * 1024' at line 1
+SELECT local.rpl_send_buffer_size;
+ERROR 42S02: Unknown table 'local' in field list
+SET global.rpl_send_buffer_size = 30 * 1024;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'global.rpl_send_buffer_size = 30 * 1024' at line 1
+SELECT global.rpl_send_buffer_size;
+ERROR 42S02: Unknown table 'global' in field list
+SELECT rpl_send_buffer_size = @@session.rpl_send_buffer_size;
+ERROR 42S22: Unknown column 'rpl_send_buffer_size' in 'field list'
+SET @@global.rpl_send_buffer_size = @start_rpl_send_buffer_size;
+SELECT @@global.rpl_send_buffer_size;
+@@global.rpl_send_buffer_size
+2097152

mysql-test/suite/sys_vars/t/rpl_send_buffer_size_basic.test

@@ -0,0 +1,132 @@
+--source include/load_sysvars.inc
+
+########################################################################
+#              START OF rpl_send_buffer_size TESTS                     #
+########################################################################
+
+
+SET @start_rpl_send_buffer_size = @@global.rpl_send_buffer_size;
+SELECT @start_rpl_send_buffer_size;
+
+--echo '#--------------------TEST_01------------------------#'
+########################################################################
+#           Display the DEFAULT value of rpl_send_buffer_size          #
+########################################################################
+
+SET @@global.rpl_send_buffer_size = 20 * 1024;
+SET @@global.rpl_send_buffer_size = DEFAULT;
+SELECT @@global.rpl_send_buffer_size;
+
+
+--echo '#---------------------TEST_02-------------------------#'
+###############################################
+#     Verify default value of variable        #
+###############################################
+
+SET @@global.rpl_send_buffer_size = @start_rpl_send_buffer_size;
+SELECT @@global.rpl_send_buffer_size = 2 * 1024 * 1024;
+
+--echo '#--------------------TEST_03------------------------#'
+########################################################################
+#    Change the value of rpl_send_buffer_size to a valid value         #
+########################################################################
+
+SET @@global.rpl_send_buffer_size = 16 * 1024;
+SELECT @@global.rpl_send_buffer_size;
+SET @@global.rpl_send_buffer_size = 128 * 1024 * 1024;
+SELECT @@global.rpl_send_buffer_size;
+SET @@global.rpl_send_buffer_size = 300 * 1024;
+SELECT @@global.rpl_send_buffer_size;
+SET @@global.rpl_send_buffer_size = 100 * 1024 * 1024;
+SELECT @@global.rpl_send_buffer_size;
+
+
+--echo '#--------------------TEST_04-------------------------#'
+#########################################################################
+#      Change the value of rpl_send_buffer_size to invalid value        #
+#########################################################################
+
+SET @@global.rpl_send_buffer_size = -1;
+SELECT @@global.rpl_send_buffer_size;
+SET @@global.rpl_send_buffer_size = 100;
+SELECT @@global.rpl_send_buffer_size;
+--Error ER_WRONG_TYPE_FOR_VAR
+SET @@global.rpl_send_buffer_size = 18446744073709551616;
+SELECT @@global.rpl_send_buffer_size;
+--Error ER_WRONG_TYPE_FOR_VAR
+SET @@global.rpl_send_buffer_size = 10000.01;
+SELECT @@global.rpl_send_buffer_size;
+
+--Error ER_WRONG_TYPE_FOR_VAR
+SET @@global.rpl_send_buffer_size = ON;
+SELECT @@global.rpl_send_buffer_size;
+--Error ER_WRONG_TYPE_FOR_VAR
+SET @@global.rpl_send_buffer_size = 'test';
+SELECT @@global.rpl_send_buffer_size;
+
+
+--echo '#-------------------TEST_05----------------------------#'
+##########################################################################
+#       Test if accessing session rpl_send_buffer_size gives error       #
+##########################################################################
+
+--Error ER_GLOBAL_VARIABLE
+SET @@session.rpl_send_buffer_size = 20 * 1024;
+--Error ER_INCORRECT_GLOBAL_LOCAL_VAR
+SELECT @@session.rpl_send_buffer_size;
+
+
+--echo '#----------------------TEST_06------------------------#'
+##############################################################################
+# Check if the value in GLOBAL & SESSION Tables matches values in variable   #
+##############################################################################
+
+SELECT @@global.rpl_send_buffer_size = VARIABLE_VALUE
+FROM performance_schema.global_variables
+WHERE VARIABLE_NAME='rpl_send_buffer_size';
+
+SELECT @@rpl_send_buffer_size = VARIABLE_VALUE
+FROM performance_schema.session_variables
+WHERE VARIABLE_NAME='rpl_send_buffer_size';
+
+
+--echo '#---------------------TEST_08----------------------#'
+########################################################################################################
+#    Check if accessing variable with SESSION,LOCAL and without SCOPE points to same session variable  #
+########################################################################################################
+
+SET @@global.rpl_send_buffer_size = 30 * 1024;
+SELECT @@rpl_send_buffer_size = @@global.rpl_send_buffer_size;
+
+
+--echo '#---------------------TEST_09----------------------#'
+################################################################################
+#   Check if rpl_send_buffer_size can be accessed with and without @@ sign     #
+################################################################################
+
+--Error ER_GLOBAL_VARIABLE
+SET rpl_send_buffer_size = 20 * 1024;
+SELECT @@rpl_send_buffer_size;
+--Error ER_PARSE_ERROR
+SET local.rpl_send_buffer_size = 20 * 1024;
+--Error ER_UNKNOWN_TABLE
+SELECT local.rpl_send_buffer_size;
+--Error ER_PARSE_ERROR
+SET global.rpl_send_buffer_size = 30 * 1024;
+--Error ER_UNKNOWN_TABLE
+SELECT global.rpl_send_buffer_size;
+--Error ER_BAD_FIELD_ERROR
+SELECT rpl_send_buffer_size = @@session.rpl_send_buffer_size;
+
+
+##############################
+#   Restore initial value    #
+##############################
+
+SET @@global.rpl_send_buffer_size = @start_rpl_send_buffer_size;
+SELECT @@global.rpl_send_buffer_size;
+
+
+######################################################################
+#              END OF rpl_send_buffer_size TESTS                     #
+######################################################################

sql/rpl_binlog_sender.cc

@@ -22,7 +22,9 @@
 
 #include "sql/rpl_binlog_sender.h"
 
+#include <errno.h>
 #include <stdio.h>
+#include <sys/socket.h>
 #include <algorithm>
 #include <atomic>
 #include <memory>
@@ -229,6 +231,8 @@ class Binlog_sender::Event_allocator {
   Binlog_sender *m_sender = nullptr;
 };
 
+uint rpl_send_buffer_size = 0;
+
 Binlog_sender::Binlog_sender(THD *thd, const char *start_file,
                              my_off_t start_pos, Gtid_set *exclude_gtids,
                              uint32 flag)
@@ -312,6 +316,18 @@ void Binlog_sender::init() {
   }
   m_transmit_started = true;
 
+  NET *net = thd->get_protocol_classic()->get_net();
+  if (rpl_send_buffer_size &&
+      (setsockopt(net->vio->mysql_socket.fd, SOL_SOCKET, SO_SNDBUF,
+                  &rpl_send_buffer_size, sizeof(rpl_send_buffer_size)) == -1
+#ifdef UNIV_LINUX
+       || setsockopt(net->vio->mysql_socket.fd, IPPROTO_TCP, TCP_WINDOW_CLAMP,
+                     &rpl_send_buffer_size, sizeof(rpl_send_buffer_size)) == -1
+#endif
+       ))
+    sql_print_warning("Failed to set SO_SNDBUF with (error: %s).",
+                      strerror(errno));
+
   init_checksum_alg();
   /*
     There are two ways to tell the server to not block:

sql/rpl_binlog_sender.h

@@ -40,6 +40,8 @@
 class String;
 class THD;
 
+extern uint rpl_send_buffer_size;
+
 /**
   The major logic of dump thread is implemented in this class. It sends
   required binlog events to clients according to their requests.

sql/sys_vars.cc

@@ -108,6 +108,7 @@
 #include "sql/protocol_classic.h"
 #include "sql/psi_memory_key.h"
 #include "sql/query_options.h"
+#include "sql/rpl_binlog_sender.h"
 #include "sql/rpl_group_replication.h"  // is_group_replication_running
 #include "sql/rpl_handler.h"            // delegates_update_lock_type
 #include "sql/rpl_info_factory.h"       // Rpl_info_factory
@@ -5796,6 +5797,13 @@ static Sys_var_ulong Sys_rpl_read_size(
     VALID_RANGE(IO_SIZE * 2, ULONG_MAX), DEFAULT(IO_SIZE * 2),
     BLOCK_SIZE(IO_SIZE));
 
+static Sys_var_uint Sys_rpl_send_buffer_size(
+    "rpl_send_buffer_size",
+    "The size of output buffer for the socket used during sending "
+    "events to a slave.",
+    GLOBAL_VAR(rpl_send_buffer_size), CMD_LINE(REQUIRED_ARG),
+    VALID_RANGE(1024, UINT_MAX), DEFAULT(2 * 1024 * 1024), BLOCK_SIZE(1024));
+
 static Sys_var_bool Sys_slave_allow_batching(
     "slave_allow_batching", "Allow slave to batch requests",
     GLOBAL_VAR(opt_slave_allow_batching), CMD_LINE(OPT_ARG), DEFAULT(false));