SET @saved_page_cleaners = @@GLOBAL.innodb_page_cleaners;
create table t1 (a int not null primary key auto_increment,
b bigint,
c varchar(200),
d int,
key b (b),
key d (d)) engine=INNODB;
set GLOBAL innodb_page_cleaners = 4;
connect  con1,localhost,root,,;
connection con1;
update t1 set b = b + 5, d = d + 1 where a between 1 and 2000;
connect  con2,localhost,root,,;
connection con2;
update t1 set b = b + 5, d = d + 1 where a between 3000 and 5000;
connect  con3,localhost,root,,;
connection con3;
update t1 set b = b + 5, d = d + 1 where a between 8000 and 12000;
connection default;
set GLOBAL innodb_page_cleaners = 2;
set GLOBAL innodb_page_cleaners = 4;
set GLOBAL innodb_page_cleaners = 6;
connection con1;
connection con2;
connection con3;
connection default;
set GLOBAL innodb_page_cleaners = 4;
connection con1;
update t1 set b = b + 5, d = d + 1 where a between 1 and 2000;
connection con2;
update t1 set b = b + 5, d = d + 1 where a between 3000 and 5000;
connection con3;
update t1 set b = b + 5, d = d + 1 where a between 8000 and 12000;
connection default;
set GLOBAL innodb_page_cleaners = 3;
set GLOBAL innodb_page_cleaners = 2;
set GLOBAL innodb_page_cleaners = 1;
connection con1;
connection con2;
connection con3;
connection default;
disconnect con1;
disconnect con2;
disconnect con3;
DROP TABLE t1;
SET GLOBAL innodb_page_cleaners=@saved_page_cleaners;