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--source include/have_innodb.inc
--source include/have_log_bin.inc
ALTER TABLE mysql.gtid_slave_pos ENGINE=InnoDB;
CREATE TABLE t1 (a INT PRIMARY KEY, b INT) ENGINE=InnoDB;
SET @old_count= @@GLOBAL.binlog_commit_wait_count;
SET GLOBAL binlog_commit_wait_count= 3;
SET @old_usec= @@GLOBAL.binlog_commit_wait_usec;
SET GLOBAL binlog_commit_wait_usec= 20000000;
connect(con1,localhost,root,,test);
connect(con2,localhost,root,,test);
connect(con3,localhost,root,,test);
# Get Initial status measurements
--connection default
SELECT variable_value INTO @group_commits FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commits';
SELECT variable_value INTO @group_commit_trigger_count FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_count';
SELECT variable_value INTO @group_commit_trigger_timeout FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_timeout';
SELECT variable_value INTO @group_commit_trigger_lock_wait FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_lock_wait';
# Note: binlog_group_commits is counted at the start of the group and group_commit_trigger_* is
# counted near when the groups its finalised.
# Check that if T2 goes to wait for a row lock of T1 while T1 is waiting for
# more transactions to arrive for group commit, the commit of T1 will complete
# immediately.
# We test this by setting a very high timeout (20 seconds), and testing that
# that much time does not elapse.
--connection default
SET @a= current_timestamp();
--connection con1
BEGIN;
INSERT INTO t1 VALUES (1,0);
send COMMIT;
--connection con2
send INSERT INTO t1 VALUES (1,1);
--connection con1
reap;
--connection default
SET @b= unix_timestamp(current_timestamp()) - unix_timestamp(@a);
SELECT IF(@b < 20, "Ok", CONCAT("Error: too much time elapsed: ", @b, " seconds >= 20"));
# All connections are to the same server. One transaction occurs on con1. It is
# commited before con2 is started. con2 transaction violates the unique key contraint. This
# type of group commit is binlog_group_commit_trigger_lock_wait so that further con2
# transactions will occur afterwards as they may be as result of the ER_DUP_ENTRY on the
# application side.
# before: binlog_group_commit=0, binlog_group_commit_trigger_count=0
# before: binlog_group_commit_trigger_timeout=0, binlog_group_commit_trigger_lock_wait=0
# after: binlog_group_commit+1 by reason of binlog_group_commit_trigger_lock_wait+1
SELECT variable_value - @group_commits FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commits';
SELECT variable_value - @group_commit_trigger_count FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_count';
SELECT variable_value - @group_commit_trigger_timeout FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_timeout';
SELECT variable_value - @group_commit_trigger_lock_wait FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_lock_wait';
--connection con2
--error ER_DUP_ENTRY
reap;
# Test that the commit triggers when sufficient commits have queued up.
--connection default
SET @a= current_timestamp();
--connection con1
send INSERT INTO t1 VALUES (2,0);
--connection con2
send INSERT INTO t1 VALUES (3,0);
--connection con3
INSERT INTO t1 VALUES (4,0);
--connection con1
reap;
--connection con2
reap;
--connection default
SET @b= unix_timestamp(current_timestamp()) - unix_timestamp(@a);
SELECT IF(@b < 20, "Ok", CONCAT("Error: too much time elapsed: ", @b, " seconds >= 20"));
# All connections are to the same server. 3 non-conflicting transaction occur
# on each connection. The binlog_commit_wait_count=3 at the start therefore 1
# group is committed by virtue of reaching 3 transactions. Hence
# binlog_group_commit_trigger_count is incremented.
# before: binlog_group_commit=1, binlog_group_commit_trigger_count=0
# before: binlog_group_commit_trigger_timeout=0, binlog_group_commit_trigger_lock_wait=1
# after: binlog_group_commit+1 by reason of binlog_group_commit_trigger_count+1
SELECT variable_value - @group_commits FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commits';
SELECT variable_value - @group_commit_trigger_count FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_count';
SELECT variable_value - @group_commit_trigger_timeout FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_timeout';
SELECT variable_value - @group_commit_trigger_lock_wait FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_lock_wait';
# Test that commit triggers immediately if there is already a transaction
# waiting on another transaction that reaches its commit.
--connection default
SET @a= current_timestamp();
--connection con1
send INSERT INTO t1 VALUES (6,0);
--connection con2
BEGIN;
UPDATE t1 SET b=b+1 WHERE a=1;
--connection con3
send UPDATE t1 SET b=b+10 WHERE a=1;
--connection con2
# A small sleep to let con3 have time to wait on con2.
# The sleep might be too small on loaded host, but that is not a big problem;
# it only means we will trigger a different code path (con3 waits after con2
# is ready to commit rather than before); and either path should work the same.
# So we will not get false positive in case of different timing; at worst false
# negative.
SELECT SLEEP(0.25);
UPDATE t1 SET b=b+1 WHERE a=3;
COMMIT;
--connection con1
reap;
--connection default
SET @b= unix_timestamp(current_timestamp()) - unix_timestamp(@a);
SELECT IF(@b < 20, "Ok", CONCAT("Error: too much time elapsed: ", @b, " seconds >= 20"));
# All connections are to the same server. con2 and con3 updates are aquiring
# the same row lock for a=1. Either con2 or con3 will be in a lock wait
# thefore the binlog_group_commit_trigger_lock_wait is incremented.
# before: binlog_group_commit=2, binlog_group_commit_trigger_count=1
# before: binlog_group_commit_trigger_timeout=0, binlog_group_commit_trigger_lock_wait=1
# after: binlog_group_commit+1 by reason of binlog_group_commit_trigger_lock_wait+1
SELECT variable_value - @group_commits FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commits';
SELECT variable_value - @group_commit_trigger_count FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_count';
SELECT variable_value - @group_commit_trigger_timeout FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_timeout';
SELECT variable_value - @group_commit_trigger_lock_wait FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_lock_wait';
--connection default
SET @a= current_timestamp();
# Now con3 will be waiting for a following group commit to trigger.
--connection con1
send INSERT INTO t1 VALUES (7,0);
--connection con2
INSERT INTO t1 VALUES (8,0);
--connection con3
reap;
--connection default
SET @b= unix_timestamp(current_timestamp()) - unix_timestamp(@a);
SELECT IF(@b < 20, "Ok", CONCAT("Error: too much time elapsed: ", @b, " seconds >= 20"));
# The con1 and con2 transactions above are combined with the 'send UPDATE t1 SET b=b+10 WHERE a=1;'
# on con3 from the previous block. So we have 3 so this is a count based group.
# before: binlog_group_commit=3, binlog_group_commit_trigger_count=1
# before: binlog_group_commit_trigger_timeout=0, binlog_group_commit_trigger_lock_wait=2
# after: binlog_group_commit+1 by reason of binlog_group_commit_trigger_count+1
SELECT variable_value - @group_commits FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commits';
SELECT variable_value - @group_commit_trigger_count FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_count';
SELECT variable_value - @group_commit_trigger_timeout FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_timeout';
SELECT variable_value - @group_commit_trigger_lock_wait FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_lock_wait';
# Test that when the binlog_commit_wait_usec is reached the tranction gets a group commit
--connection default
SET @a= current_timestamp();
SET GLOBAL binlog_commit_wait_usec= 5*1000*1000;
--connection con1
reap;
INSERT INTO t1 VALUES (9,0);
--connection default
SET @b= unix_timestamp(current_timestamp()) - unix_timestamp(@a);
SELECT IF(@b < 4, CONCAT("Error: too little time elapsed: ", @b, " seconds < 4"),
IF(@b < 20, "Ok", CONCAT("Error: too much time elapsed: ", @b, " seconds >= 20")));
# con1 pushes 1 transaction. The count was for 3 to occur before a group commit.
# The timeout is 5 seconds but we allow between 4 and 20 because of the fragile nature
# of time in test. This is a timeout causing the commit so binlog_group_commit_trigger_timeout
# is incremented.
# before: binlog_group_commit=4, binlog_group_commit_trigger_count=2
# before: binlog_group_commit_trigger_timeout=0, binlog_group_commit_trigger_lock_wait=2
# after: binlog_group_commit+1 by reason of binlog_group_commit_trigger_timeout+1
SELECT variable_value - @group_commits FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commits';
SELECT variable_value - @group_commit_trigger_count FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_count';
SELECT variable_value - @group_commit_trigger_timeout FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_timeout';
SELECT variable_value - @group_commit_trigger_lock_wait FROM information_schema.global_status
WHERE variable_name = 'binlog_group_commit_trigger_lock_wait';
--connection default
SELECT * FROM t1 ORDER BY a;
--connection default
DROP TABLE t1;
SET GLOBAL binlog_commit_wait_count= @old_count;
SET GLOBAL binlog_commit_wait_usec= @old_usec;
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