MDEV-21360 debug_dbug pre-test value restoration issues

72 files changed, 144 insertions, 74 deletions

diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_allow.result
index 27243b52422..24f6a448334 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_again";
 connect  con2,"127.0.0.1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'192.0.2.4';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_deny.result
index 7879919b09d..a4072a4681a 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_again_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_again";
 ERROR HY000: Host '192.0.2.4' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_allow.result
index 1d5923483c9..277eb5a57f3 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_bad_ipv4";
 connect  con2,"127.0.0.1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'192.0.2.4';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_deny.result
index 87fc75817df..716089f7022 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_bad_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_bad_ipv4";
 ERROR HY000: Host '192.0.2.4' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_allow.result
index 949fa8f9c3e..e7ef6c05d4b 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 connect  con2,"127.0.0.1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	null
 LAST_ERROR_SEEN	null
 revoke select on test.* from 'root'@'santa.claus.ipv4.example.com';
 drop user 'root'@'santa.claus.ipv4.example.com';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_deny.result
index b2e0fb60811..a516f77a66d 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_good_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 ERROR HY000: Host 'santa.claus.ipv4.example.com' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_allow.result
index bfc7fde5be8..d6212a009cb 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_allow.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_noname";
 connect  con2,"127.0.0.1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -103,4 +104,4 @@ revoke select on test.* from 'root'@'santa.claus.ipv4.example.com';
 revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'santa.claus.ipv4.example.com';
 drop user 'root'@'192.0.2.4';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_deny.result
index 41eb9636e31..08f4152fdcc 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_addrinfo_noname_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_noname";
 ERROR HY000: Host '192.0.2.4' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_auth_plugin.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_auth_plugin.result
index 22dd7e7632c..7dd56fffdca 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_auth_plugin.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_auth_plugin.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 uninstall plugin test_plugin_server;
 ERROR HY000: Plugin 'test_plugin_server' is not loaded
@@ -194,5 +195,5 @@ REVOKE PROXY ON 'plug_dest'@'santa.claus.ipv4.example.com'
   FROM 'plug'@'santa.claus.ipv4.example.com';
 DROP USER 'plug'@'santa.claus.ipv4.example.com';
 DROP USER 'plug_dest'@'santa.claus.ipv4.example.com';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 delete from mysql.plugin where name='test_plugin_server';
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_blocked.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_blocked.result
index f301df94ce6..33000173925 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_blocked.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_blocked.result
@@ -25,6 +25,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4,native_password_bad_reply";
 ERROR 08S01: Bad handshake
 connection default;
@@ -427,4 +428,4 @@ drop user 'root'@'santa.claus.ipv4.example.com';
 revoke select on test.* from 'quota'@'santa.claus.ipv4.example.com';
 drop user 'quota'@'santa.claus.ipv4.example.com';
 set global max_connect_errors = @saved_max_connect_errors;
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_format.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_format.result
index 14a6ace09e4..8af7cadda99 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_format.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_format.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_format_ipv4";
 ERROR HY000: Host '192.0.2.4' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_max_con.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_max_con.result
index 6cca75f9775..75d784e3381 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_max_con.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_max_con.result
@@ -25,6 +25,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 connect  con2a,"127.0.0.1",quota,,test,$MASTER_MYPORT,;
 select "Con2a is alive";
@@ -702,4 +703,4 @@ disconnect tmp_con7;
 set global max_connections = @saved_max_connections;
 set global max_user_connections = @saved_max_user_connections;
 drop user 'quota'@'santa.claus.ipv4.example.com';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_allow.result
index 5aa80d90d84..6f80a0883a3 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_allow.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_again";
 connect  con2,"127.0.0.1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -178,4 +179,4 @@ revoke select on test.* from 'root'@'192.0.2.4';
 revoke select on test.* from 'root'@'santa.claus.ipv4.example.com';
 drop user 'root'@'192.0.2.4';
 drop user 'root'@'santa.claus.ipv4.example.com';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_deny.result
index abe9a606bc4..0a80efd3333 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_again_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_again";
 ERROR HY000: Host '192.0.2.4' is not allowed to connect to this MariaDB server
 connection default;
@@ -142,4 +143,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_allow.result
index 18986674491..9499789334b 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_noname";
 connect  con2,"127.0.0.1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'192.0.2.4';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_deny.result
index 88ac817ce17..2592a003d59 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_nameinfo_noname_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_noname";
 ERROR HY000: Host '192.0.2.4' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_passwd.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_passwd.result
index a5f70873ed9..fc20f4e1c2f 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_passwd.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_passwd.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 ERROR 28000: Access denied for user 'user_without'@'santa.claus.ipv4.example.com' (using password: YES)
 connection default;
@@ -207,4 +208,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 drop user 'user_with'@'santa.claus.ipv4.example.com';
 drop user 'user_without'@'santa.claus.ipv4.example.com';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv4_ssl.result b/mysql-test/suite/perfschema/r/hostcache_ipv4_ssl.result
index 86e7bf5780b..c7ae1cdd12f 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv4_ssl.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv4_ssl.result
@@ -28,6 +28,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 ERROR 28000: Access denied for user 'user_ssl'@'santa.claus.ipv4.example.com' (using password: NO)
 connection default;
@@ -151,4 +152,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 drop user 'user_ssl'@'santa.claus.ipv4.example.com';
 drop user 'user_ssl_x509'@'santa.claus.ipv4.example.com';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_allow.result
index 42d86e858fb..330aaa57b1d 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_again";
 connect  con2,"::1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'2001:db8::6:6';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_deny.result
index 87e97ba2138..dd730123cc4 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_again_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_again";
 ERROR HY000: Host '2001:db8::6:6' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_allow.result
index bcd47243d03..c613bda07ba 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_bad_ipv6";
 connect  con2,"::1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'2001:db8::6:6';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_deny.result
index 5c24a86248a..32fcc37b75b 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_bad_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_bad_ipv6";
 ERROR HY000: Host '2001:db8::6:6' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_allow.result
index 68ea9a1d826..2558047ab62 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 connect  con2,"::1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	null
 LAST_ERROR_SEEN	null
 revoke select on test.* from 'root'@'santa.claus.ipv6.example.com';
 drop user 'root'@'santa.claus.ipv6.example.com';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_deny.result
index 5b1f546b30e..a4da4f54058 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_good_deny.result
@@ -19,6 +19,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 ERROR HY000: Host 'santa.claus.ipv6.example.com' is not allowed to connect to this MariaDB server
 connection default;
@@ -80,4 +81,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_allow.result
index 0a3a3329c1e..e4da1079176 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_allow.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_noname";
 connect  con2,"::1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -103,4 +104,4 @@ revoke select on test.* from 'root'@'santa.claus.ipv6.example.com';
 revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'santa.claus.ipv6.example.com';
 drop user 'root'@'2001:db8::6:6';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_deny.result
index 493ada909b7..2aeb0189da4 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_addrinfo_noname_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_noname";
 ERROR HY000: Host '2001:db8::6:6' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_auth_plugin.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_auth_plugin.result
index a36d1442ee6..0897fdd1872 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_auth_plugin.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_auth_plugin.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 uninstall plugin test_plugin_server;
 ERROR HY000: Plugin 'test_plugin_server' is not loaded
@@ -194,5 +195,5 @@ REVOKE PROXY ON 'plug_dest'@'santa.claus.ipv6.example.com'
   FROM 'plug'@'santa.claus.ipv6.example.com';
 DROP USER 'plug'@'santa.claus.ipv6.example.com';
 DROP USER 'plug_dest'@'santa.claus.ipv6.example.com';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 delete from mysql.plugin where name='test_plugin_server';
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_blocked.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_blocked.result
index 7cfb6f87277..c4d482a6b12 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_blocked.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_blocked.result
@@ -25,6 +25,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6,native_password_bad_reply";
 ERROR 08S01: Bad handshake
 connection default;
@@ -427,4 +428,4 @@ drop user 'root'@'santa.claus.ipv6.example.com';
 revoke select on test.* from 'quota'@'santa.claus.ipv6.example.com';
 drop user 'quota'@'santa.claus.ipv6.example.com';
 set global max_connect_errors = @saved_max_connect_errors;
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_max_con.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_max_con.result
index f9d2b556804..a77603b6e99 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_max_con.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_max_con.result
@@ -25,6 +25,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 connect  con2a,"::1",quota,,test,$MASTER_MYPORT,;
 select "Con2a is alive";
@@ -702,4 +703,4 @@ disconnect tmp_con7;
 set global max_connections = @saved_max_connections;
 set global max_user_connections = @saved_max_user_connections;
 drop user 'quota'@'santa.claus.ipv6.example.com';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_allow.result
index 6140f655e7c..3227b1eec67 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_allow.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_again";
 connect  con2,"::1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -178,4 +179,4 @@ revoke select on test.* from 'root'@'2001:db8::6:6';
 revoke select on test.* from 'root'@'santa.claus.ipv6.example.com';
 drop user 'root'@'2001:db8::6:6';
 drop user 'root'@'santa.claus.ipv6.example.com';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_deny.result
index 22ce0c3e809..b801010e0b7 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_again_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_again";
 ERROR HY000: Host '2001:db8::6:6' is not allowed to connect to this MariaDB server
 connection default;
@@ -142,4 +143,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_allow.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_allow.result
index a78ba09513c..a17421161f9 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_allow.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_allow.result
@@ -22,6 +22,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_noname";
 connect  con2,"::1",root,,test,$MASTER_MYPORT,;
 select "Con2 is alive";
@@ -99,4 +100,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'2001:db8::6:6';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_deny.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_deny.result
index da1570f1b37..dd1b2f89ac3 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_deny.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_nameinfo_noname_deny.result
@@ -20,6 +20,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_noname";
 ERROR HY000: Host '2001:db8::6:6' is not allowed to connect to this MariaDB server
 connection default;
@@ -81,4 +82,4 @@ COUNT_LOCAL_ERRORS	0
 COUNT_UNKNOWN_ERRORS	0
 FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_passwd.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_passwd.result
index a4cc3eeb0d0..6d6362b2874 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_passwd.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_passwd.result
@@ -24,6 +24,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 ERROR 28000: Access denied for user 'user_without'@'santa.claus.ipv6.example.com' (using password: YES)
 connection default;
@@ -207,4 +208,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 drop user 'user_with'@'santa.claus.ipv6.example.com';
 drop user 'user_without'@'santa.claus.ipv6.example.com';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_ipv6_ssl.result b/mysql-test/suite/perfschema/r/hostcache_ipv6_ssl.result
index 75f8e5391cf..61c98b0c868 100644
--- a/mysql-test/suite/perfschema/r/hostcache_ipv6_ssl.result
+++ b/mysql-test/suite/perfschema/r/hostcache_ipv6_ssl.result
@@ -28,6 +28,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 ERROR 28000: Access denied for user 'user_ssl'@'santa.claus.ipv6.example.com' (using password: NO)
 connection default;
@@ -151,4 +152,4 @@ FIRST_ERROR_SEEN	set
 LAST_ERROR_SEEN	set
 drop user 'user_ssl'@'santa.claus.ipv6.example.com';
 drop user 'user_ssl_x509'@'santa.claus.ipv6.example.com';
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/r/hostcache_peer_addr.result b/mysql-test/suite/perfschema/r/hostcache_peer_addr.result
index ddb44157f44..d88a240a2b7 100644
--- a/mysql-test/suite/perfschema/r/hostcache_peer_addr.result
+++ b/mysql-test/suite/perfschema/r/hostcache_peer_addr.result
@@ -27,6 +27,7 @@ current_user()
 root@localhost
 disconnect con1;
 connection default;
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_error";
 ERROR HY000: Can't get hostname for your address
 connection default;
@@ -50,7 +51,7 @@ Connection_errors_peer_address	2
 Connection_errors_select	0
 Connection_errors_tcpwrap	0
 "Dumping performance_schema.host_cache"
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 flush status;
 show global status like "connection_errors_%";
 Variable_name	Value
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_allow.test
index 6bed01e50bf..07a6f14f114 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_allow.test
@@ -27,6 +27,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_again";
 
 connect (con2,"127.0.0.1",root,,test,$MASTER_MYPORT,);
@@ -48,5 +49,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'192.0.2.4';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_deny.test
index 3c72de8a05e..1218538d173 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_again_deny.test
@@ -25,6 +25,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_again";
 
 --disable_query_log
@@ -43,5 +44,5 @@ connect (con3,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_allow.test
index 5cbe4c30530..285563ddc62 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_allow.test
@@ -30,6 +30,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_bad_ipv4";
 
 connect (con2,"127.0.0.1",root,,test,$MASTER_MYPORT,);
@@ -51,5 +52,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'192.0.2.4';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_deny.test
index c0639cd6b86..a7d197e03d1 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_bad_deny.test
@@ -27,6 +27,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_bad_ipv4";
 
 --disable_query_log
@@ -45,5 +46,5 @@ connect (con3,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_allow.test
index 3b69e0731a0..0f8881e3caa 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_allow.test
@@ -28,6 +28,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 
 connect (con2,"127.0.0.1",root,,test,$MASTER_MYPORT,);
@@ -49,5 +50,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'santa.claus.ipv4.example.com';
 drop user 'root'@'santa.claus.ipv4.example.com';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_deny.test
index e6478c13951..dd2c7209e54 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_good_deny.test
@@ -25,6 +25,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 
 --disable_query_log
@@ -43,5 +44,5 @@ connect (con3,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_allow.test
index b4b11526af6..12f82b2a52c 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_allow.test
@@ -30,6 +30,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_noname";
 
 connect (con2,"127.0.0.1",root,,test,$MASTER_MYPORT,);
@@ -53,5 +54,5 @@ revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'santa.claus.ipv4.example.com';
 drop user 'root'@'192.0.2.4';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_deny.test
index 06f0f7d29ee..28030802afb 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_addrinfo_noname_deny.test
@@ -25,6 +25,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_error_noname";
 
 --disable_query_log
@@ -43,5 +44,5 @@ connect (con3,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_auth_plugin.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_auth_plugin.test
index 325460e66ba..3e487f38636 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_auth_plugin.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_auth_plugin.test
@@ -30,6 +30,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 uninstall plugin test_plugin_server;
 
@@ -86,6 +87,6 @@ REVOKE PROXY ON 'plug_dest'@'santa.claus.ipv4.example.com'
 DROP USER 'plug'@'santa.claus.ipv4.example.com';
 DROP USER 'plug_dest'@'santa.claus.ipv4.example.com';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 delete from mysql.plugin where name='test_plugin_server';
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_blocked.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_blocked.test
index 6990a4e7118..59cd855feaf 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_blocked.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_blocked.test
@@ -33,6 +33,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4,native_password_bad_reply";
 
 --disable_query_log
@@ -156,5 +157,5 @@ revoke select on test.* from 'quota'@'santa.claus.ipv4.example.com';
 drop user 'quota'@'santa.claus.ipv4.example.com';
 
 set global max_connect_errors = @saved_max_connect_errors;
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_format.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_format.test
index b37bfc79ada..a7c0117284d 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_format.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_format.test
@@ -24,6 +24,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_format_ipv4";
 
 --disable_query_log
@@ -42,5 +43,5 @@ connect (con3,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_max_con.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_max_con.test
index c0349184506..904de7335ee 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_max_con.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_max_con.test
@@ -31,6 +31,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 
 connect (con2a,"127.0.0.1",quota,,test,$MASTER_MYPORT,);
@@ -259,5 +260,5 @@ set global max_user_connections = @saved_max_user_connections;
 # revoke all privileges on test.* from 'quota'@'santa.claus.ipv4.example.com';
 drop user 'quota'@'santa.claus.ipv4.example.com';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_allow.test
index 187879985c9..0a83bc51f12 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_allow.test
@@ -30,6 +30,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_again";
 
 connect (con2,"127.0.0.1",root,,test,$MASTER_MYPORT,);
@@ -71,5 +72,5 @@ revoke select on test.* from 'root'@'santa.claus.ipv4.example.com';
 drop user 'root'@'192.0.2.4';
 drop user 'root'@'santa.claus.ipv4.example.com';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_deny.test
index a78c0dab4eb..465133859d2 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_again_deny.test
@@ -25,6 +25,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_again";
 
 --disable_query_log
@@ -61,5 +62,5 @@ connect (con5,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_allow.test
index 23ecd51eb4f..15153dd07aa 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_allow.test
@@ -28,6 +28,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_noname";
 
 connect (con2,"127.0.0.1",root,,test,$MASTER_MYPORT,);
@@ -49,5 +50,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'192.0.2.4';
 drop user 'root'@'192.0.2.4';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_deny.test
index 4b6c91c3df3..9df41d429f2 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_nameinfo_noname_deny.test
@@ -25,6 +25,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_error_noname";
 
 --disable_query_log
@@ -43,5 +44,5 @@ connect (con3,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_passwd.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_passwd.test
index ea331647b48..064200f80b8 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_passwd.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_passwd.test
@@ -29,6 +29,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 
 --disable_query_log
@@ -82,5 +83,5 @@ connect (con2f,"127.0.0.1",user_with,wrong_password,test,$MASTER_MYPORT,);
 drop user 'user_with'@'santa.claus.ipv4.example.com';
 drop user 'user_without'@'santa.claus.ipv4.example.com';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv4_ssl.test b/mysql-test/suite/perfschema/t/hostcache_ipv4_ssl.test
index 2b949098bad..116ad07dd68 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv4_ssl.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv4_ssl.test
@@ -30,6 +30,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv4,getnameinfo_fake_ipv4,getaddrinfo_fake_good_ipv4";
 
 --disable_query_log
@@ -67,5 +68,5 @@ connect (con2d,"127.0.0.1",user_ssl_x509,good_password,test,$MASTER_MYPORT,,SSL)
 drop user 'user_ssl'@'santa.claus.ipv4.example.com';
 drop user 'user_ssl_x509'@'santa.claus.ipv4.example.com';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_allow.test
index 11c45724f70..a45da8c614a 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_allow.test
@@ -29,6 +29,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_again";
 
 connect (con2,"::1",root,,test,$MASTER_MYPORT,);
@@ -50,5 +51,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'2001:db8::6:6';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_deny.test
index bdbc0e3c025..c9102366a7d 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_again_deny.test
@@ -26,6 +26,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_again";
 
 --disable_query_log
@@ -44,5 +45,5 @@ connect (con3,"::1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_allow.test
index 1eb0d3ec41f..e6c5c9c7d7b 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_allow.test
@@ -31,6 +31,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_bad_ipv6";
 
 connect (con2,"::1",root,,test,$MASTER_MYPORT,);
@@ -52,5 +53,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'2001:db8::6:6';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_deny.test
index f8a3cc23c00..7a9fa037079 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_bad_deny.test
@@ -28,6 +28,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_bad_ipv6";
 
 --disable_query_log
@@ -46,5 +47,5 @@ connect (con3,"::1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_allow.test
index 6493bb61a1a..507e04f8d3f 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_allow.test
@@ -29,6 +29,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 
 connect (con2,"::1",root,,test,$MASTER_MYPORT,);
@@ -50,5 +51,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'santa.claus.ipv6.example.com';
 drop user 'root'@'santa.claus.ipv6.example.com';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_deny.test
index 065ae02dd49..5bd4d8a7bd0 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_good_deny.test
@@ -22,6 +22,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 
 --disable_query_log
@@ -40,5 +41,5 @@ connect (con3,"::1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_allow.test
index 9ebafc9627d..dd790e77dbd 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_allow.test
@@ -31,6 +31,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_noname";
 
 connect (con2,"::1",root,,test,$MASTER_MYPORT,);
@@ -54,5 +55,4 @@ revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'santa.claus.ipv6.example.com';
 drop user 'root'@'2001:db8::6:6';
 
-set global debug_dbug= default;
-
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_deny.test
index 136b3c7a24f..c6cb78da508 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_addrinfo_noname_deny.test
@@ -26,6 +26,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_error_noname";
 
 --disable_query_log
@@ -44,5 +45,4 @@ connect (con3,"::1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
-
+set @@global.debug_dbug = @saved_dbug;
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_auth_plugin.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_auth_plugin.test
index 3a822bfacb3..e8b8c42fd8a 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_auth_plugin.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_auth_plugin.test
@@ -31,6 +31,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 uninstall plugin test_plugin_server;
 
@@ -87,6 +88,6 @@ REVOKE PROXY ON 'plug_dest'@'santa.claus.ipv6.example.com'
 DROP USER 'plug'@'santa.claus.ipv6.example.com';
 DROP USER 'plug_dest'@'santa.claus.ipv6.example.com';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 delete from mysql.plugin where name='test_plugin_server';
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_blocked.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_blocked.test
index 0a04ec306cf..b28917d6ddd 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_blocked.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_blocked.test
@@ -33,6 +33,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6,native_password_bad_reply";
 
 --disable_query_log
@@ -156,5 +157,5 @@ revoke select on test.* from 'quota'@'santa.claus.ipv6.example.com';
 drop user 'quota'@'santa.claus.ipv6.example.com';
 
 set global max_connect_errors = @saved_max_connect_errors;
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_max_con.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_max_con.test
index b14fff1cc72..a2782619b15 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_max_con.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_max_con.test
@@ -32,6 +32,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 
 connect (con2a,"::1",quota,,test,$MASTER_MYPORT,);
@@ -241,5 +242,5 @@ set global max_user_connections = @saved_max_user_connections;
 # revoke all privileges on test.* from 'quota'@'santa.claus.ipv6.example.com';
 drop user 'quota'@'santa.claus.ipv6.example.com';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_allow.test
index b44b58eb0d5..c1cc68a10e1 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_allow.test
@@ -31,6 +31,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_again";
 
 connect (con2,"::1",root,,test,$MASTER_MYPORT,);
@@ -72,5 +73,5 @@ revoke select on test.* from 'root'@'santa.claus.ipv6.example.com';
 drop user 'root'@'2001:db8::6:6';
 drop user 'root'@'santa.claus.ipv6.example.com';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_deny.test
index 073451c7e75..80fccd6924f 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_again_deny.test
@@ -26,6 +26,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_again";
 
 --disable_query_log
@@ -62,5 +63,5 @@ connect (con5,"::1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_allow.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_allow.test
index a7b1a961f09..af809674711 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_allow.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_allow.test
@@ -29,6 +29,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_noname";
 
 connect (con2,"::1",root,,test,$MASTER_MYPORT,);
@@ -50,5 +51,5 @@ disconnect con3;
 revoke select on test.* from 'root'@'2001:db8::6:6';
 drop user 'root'@'2001:db8::6:6';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_deny.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_deny.test
index 5c3d643b166..5e3f3b605d4 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_deny.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_nameinfo_noname_deny.test
@@ -26,6 +26,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_error_noname";
 
 --disable_query_log
@@ -44,5 +45,5 @@ connect (con3,"::1",root,,test,$MASTER_MYPORT,);
 --connection default
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_passwd.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_passwd.test
index 7dcfbb922e5..a5d635d6133 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_passwd.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_passwd.test
@@ -27,6 +27,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 
 --disable_query_log
@@ -80,5 +81,5 @@ connect (con2f,"::1",user_with,wrong_password,test,$MASTER_MYPORT,);
 drop user 'user_with'@'santa.claus.ipv6.example.com';
 drop user 'user_without'@'santa.claus.ipv6.example.com';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_ipv6_ssl.test b/mysql-test/suite/perfschema/t/hostcache_ipv6_ssl.test
index 3ea4451c7aa..9821b4f8882 100644
--- a/mysql-test/suite/perfschema/t/hostcache_ipv6_ssl.test
+++ b/mysql-test/suite/perfschema/t/hostcache_ipv6_ssl.test
@@ -31,6 +31,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_fake_ipv6,getnameinfo_fake_ipv6,getaddrinfo_fake_good_ipv6";
 
 --disable_query_log
@@ -68,5 +69,5 @@ connect (con2d,"::1",user_ssl_x509,good_password,test,$MASTER_MYPORT,,SSL);
 drop user 'user_ssl'@'santa.claus.ipv6.example.com';
 drop user 'user_ssl_x509'@'santa.claus.ipv6.example.com';
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
diff --git a/mysql-test/suite/perfschema/t/hostcache_peer_addr.test b/mysql-test/suite/perfschema/t/hostcache_peer_addr.test
index 65f33ce73a8..cd36c88ffae 100644
--- a/mysql-test/suite/perfschema/t/hostcache_peer_addr.test
+++ b/mysql-test/suite/perfschema/t/hostcache_peer_addr.test
@@ -22,6 +22,7 @@ select current_user();
 disconnect con1;
 
 --connection default
+set @saved_dbug = @@global.debug_dbug;
 set global debug_dbug= "+d,vio_peer_addr_error";
 
 --disable_query_log
@@ -42,7 +43,7 @@ connect (con3,"127.0.0.1",root,,test,$MASTER_MYPORT,);
 show global status like "connection_errors_%";
 --source ../include/hostcache_dump.inc
 
-set global debug_dbug= default;
+set @@global.debug_dbug = @saved_dbug;
 
 flush status;
 show global status like "connection_errors_%";