MDEV-35813: more robust test case

Let us integrate the test case with innodb.page_cleaner so that there
will be less interference from log writes due to checkpoints.
Also, make the test compatible with ./mtr --cursor-protocol.

mysql-test/suite/innodb/r/log_write.result

@@ -1,11 +0,0 @@
-# MDEV-35813 Unnecessary InnoDB log writes in INSERT…SELECT
-CREATE TABLE t1 (a INT PRIMARY KEY) ENGINE=InnoDB STATS_PERSISTENT=0;
-SET GLOBAL innodb_max_purge_lag_wait=0;
-SELECT variable_value INTO @log_writes FROM information_schema.global_status
-WHERE variable_name='innodb_log_writes';
-INSERT INTO t1 SELECT * FROM t1;
-SELECT variable_value-@log_writes FROM information_schema.global_status
-WHERE variable_name='innodb_log_writes';
-variable_value-@log_writes
-0
-DROP TABLE t1;

mysql-test/suite/innodb/r/page_cleaner.result

@@ -2,8 +2,31 @@ SET @save_pct= @@GLOBAL.innodb_max_dirty_pages_pct;
 SET @save_pct_lwm= @@GLOBAL.innodb_max_dirty_pages_pct_lwm;
 SET GLOBAL innodb_max_dirty_pages_pct_lwm=0.0;
 SET GLOBAL innodb_max_dirty_pages_pct=0.0;
+CREATE TABLE t(a INT PRIMARY KEY) ENGINE=InnoDB STATS_PERSISTENT=0;
+connect  prevent_purge,localhost,root;
+START TRANSACTION WITH CONSISTENT SNAPSHOT;
+connection default;
+SET GLOBAL innodb_max_purge_lag_wait=0;
 SET GLOBAL innodb_max_dirty_pages_pct=90.0;
-CREATE TABLE t ENGINE=InnoDB SELECT * FROM seq_1_to_10000;
+SELECT variable_value INTO @log_writes FROM information_schema.global_status
+WHERE variable_name='innodb_log_writes';
+BEGIN;
+INSERT INTO t SELECT * FROM seq_1_to_500;
+INSERT INTO t SELECT * FROM seq_501_to_1000;
+INSERT INTO t SELECT * FROM seq_1001_to_1500;
+INSERT INTO t SELECT * FROM seq_1501_to_2000;
+INSERT INTO t SELECT * FROM seq_2001_to_2500;
+INSERT INTO t SELECT * FROM seq_2501_to_3000;
+INSERT INTO t SELECT * FROM seq_3001_to_3500;
+INSERT INTO t SELECT * FROM seq_3501_to_4000;
+INSERT INTO t SELECT * FROM seq_4001_to_4500;
+INSERT INTO t SELECT * FROM seq_4501_to_5000;
+ROLLBACK;
+SELECT if(variable_value-@log_writes<10,'ok',variable_value-@log_writes)
+FROM information_schema.global_status WHERE variable_name='innodb_log_writes';
+if(variable_value-@log_writes<10,'ok',variable_value-@log_writes)
+ok
+disconnect prevent_purge;
 SELECT variable_value>0 FROM information_schema.global_status
 WHERE variable_name = 'INNODB_BUFFER_POOL_PAGES_DIRTY';
 variable_value>0

mysql-test/suite/innodb/t/log_write.test

@@ -1,12 +0,0 @@
---source include/have_innodb.inc
-
---echo # MDEV-35813 Unnecessary InnoDB log writes in INSERT…SELECT
-
-CREATE TABLE t1 (a INT PRIMARY KEY) ENGINE=InnoDB STATS_PERSISTENT=0;
-SET GLOBAL innodb_max_purge_lag_wait=0;
-SELECT variable_value INTO @log_writes FROM information_schema.global_status
-WHERE variable_name='innodb_log_writes';
-INSERT INTO t1 SELECT * FROM t1;
-SELECT variable_value-@log_writes FROM information_schema.global_status
-WHERE variable_name='innodb_log_writes';
-DROP TABLE t1;

mysql-test/suite/innodb/t/page_cleaner.test

@@ -7,6 +7,12 @@ SET @save_pct_lwm= @@GLOBAL.innodb_max_dirty_pages_pct_lwm;
 SET GLOBAL innodb_max_dirty_pages_pct_lwm=0.0;
 SET GLOBAL innodb_max_dirty_pages_pct=0.0;
 
+CREATE TABLE t(a INT PRIMARY KEY) ENGINE=InnoDB STATS_PERSISTENT=0;
+--connect (prevent_purge,localhost,root)
+START TRANSACTION WITH CONSISTENT SNAPSHOT;
+--connection default
+SET GLOBAL innodb_max_purge_lag_wait=0;
+
 let $wait_condition =
 SELECT variable_value = 0
 FROM information_schema.global_status
@@ -15,7 +21,27 @@ WHERE variable_name = 'INNODB_BUFFER_POOL_PAGES_DIRTY';
 
 SET GLOBAL innodb_max_dirty_pages_pct=90.0;
 
-CREATE TABLE t ENGINE=InnoDB SELECT * FROM seq_1_to_10000;
+--disable_cursor_protocol
+SELECT variable_value INTO @log_writes FROM information_schema.global_status
+WHERE variable_name='innodb_log_writes';
+--enable_cursor_protocol
+
+BEGIN;
+INSERT INTO t SELECT * FROM seq_1_to_500;
+INSERT INTO t SELECT * FROM seq_501_to_1000;
+INSERT INTO t SELECT * FROM seq_1001_to_1500;
+INSERT INTO t SELECT * FROM seq_1501_to_2000;
+INSERT INTO t SELECT * FROM seq_2001_to_2500;
+INSERT INTO t SELECT * FROM seq_2501_to_3000;
+INSERT INTO t SELECT * FROM seq_3001_to_3500;
+INSERT INTO t SELECT * FROM seq_3501_to_4000;
+INSERT INTO t SELECT * FROM seq_4001_to_4500;
+INSERT INTO t SELECT * FROM seq_4501_to_5000;
+ROLLBACK;
+
+SELECT if(variable_value-@log_writes<10,'ok',variable_value-@log_writes)
+FROM information_schema.global_status WHERE variable_name='innodb_log_writes';
+--disconnect prevent_purge
 
 SELECT variable_value>0 FROM information_schema.global_status
 WHERE variable_name = 'INNODB_BUFFER_POOL_PAGES_DIRTY';