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drop table if exists t1, t2;
create table t1 (
a int not null auto_increment,
b char(16) not null,
primary key (a),
key (b)
) engine=maria row_format=dynamic;
create table t2(
a int not null auto_increment,
b char(16) not null,
primary key (a),
key (b)
) engine=maria row_format=dynamic;
insert into t1(b) values
('test0'),
('test1'),
('test2'),
('test3'),
('test4'),
('test5'),
('test6'),
('test7');
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
select count(*) from t1;
count(*)
33448
select count(*) from t2;
count(*)
20672
flush tables;
flush status;
show status like "maria_pagecache_read%";
Variable_name Value
Maria_pagecache_read_requests 211388
Maria_pagecache_reads 115
select count(*) from t1 where b = 'test1';
count(*)
4181
show status like "maria_pagecache_read%";
Variable_name Value
Maria_pagecache_read_requests 211414
Maria_pagecache_reads 122
select count(*) from t1 where b = 'test1';
count(*)
4181
show status like "maria_pagecache_read%";
Variable_name Value
Maria_pagecache_read_requests 211440
Maria_pagecache_reads 122
flush tables;
flush status;
select @@preload_buffer_size;
@@preload_buffer_size
32768
load index into cache t1;
Table Op Msg_type Msg_text
test.t1 preload_keys status OK
show status like "maria_pagecache_read%";
Variable_name Value
Maria_pagecache_read_requests 211511
Maria_pagecache_reads 193
select count(*) from t1 where b = 'test1';
count(*)
4181
show status like "maria_pagecache_read%";
Variable_name Value
Maria_pagecache_read_requests 211537
Maria_pagecache_reads 193
flush tables;
flush status;
show status like "maria_pagecache_read%";
Variable_name Value
Maria_pagecache_read_requests 211537
Maria_pagecache_reads 193
set session preload_buffer_size=256*1024;
select @@preload_buffer_size;
@@preload_buffer_size
262144
load index into cache t1 ignore leaves;
Table Op Msg_type Msg_text
test.t1 preload_keys status OK
show status like "maria_pagecache_read%";
Variable_name Value
Maria_pagecache_read_requests 211608
Maria_pagecache_reads 264
select count(*) from t1 where b = 'test1';
count(*)
4181
show status like "maria_pagecache_read%";
Variable_name Value
Maria_pagecache_read_requests 211634
Maria_pagecache_reads 270
flush tables;
flush status;
show status like "maria_pagecache_read%";
Variable_name Value
Maria_pagecache_read_requests 211634
Maria_pagecache_reads 270
set session preload_buffer_size=1*1024;
select @@preload_buffer_size;
@@preload_buffer_size
1024
load index into cache t1, t2 key (primary,b) ignore leaves;
Table Op Msg_type Msg_text
test.t1 preload_keys status OK
test.t2 preload_keys status OK
show status like "maria_pagecache_read%";
Variable_name Value
Maria_pagecache_read_requests 211748
Maria_pagecache_reads 384
select count(*) from t1 where b = 'test1';
count(*)
4181
select count(*) from t2 where b = 'test1';
count(*)
2584
show status like "maria_pagecache_read%";
Variable_name Value
Maria_pagecache_read_requests 211788
Maria_pagecache_reads 387
flush tables;
flush status;
show status like "maria_pagecache_read%";
Variable_name Value
Maria_pagecache_read_requests 211788
Maria_pagecache_reads 387
load index into cache t3, t2 key (primary,b) ;
Table Op Msg_type Msg_text
test.t3 preload_keys Error Table 'test.t3' doesn't exist
test.t3 preload_keys error Corrupt
test.t2 preload_keys status OK
show status like "maria_pagecache_read%";
Variable_name Value
Maria_pagecache_read_requests 211831
Maria_pagecache_reads 430
flush tables;
flush status;
show status like "maria_pagecache_read%";
Variable_name Value
Maria_pagecache_read_requests 211831
Maria_pagecache_reads 430
load index into cache t3 key (b), t2 key (c) ;
Table Op Msg_type Msg_text
test.t3 preload_keys Error Table 'test.t3' doesn't exist
test.t3 preload_keys error Corrupt
test.t2 preload_keys Error Key 'c' doesn't exist in table 't2'
test.t2 preload_keys status Operation failed
show status like "maria_pagecache_read%";
Variable_name Value
Maria_pagecache_read_requests 211831
Maria_pagecache_reads 430
drop table t1, t2;
show status like "key_read%";
Variable_name Value
Key_read_requests 0
Key_reads 0
|
