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Bug #23070734 CONCURRENT TRUNCATE TABLES CAUSE STALLS

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PROBLEM

When truncating single tablespace tables, we need to scan the entire
buffer pool to remove the pages of the table from the buffer pool.
During this scan and removal dict_sys->mutex is being held ,causing
stalls in other DDL operations.

FIX

Release the dict_sys->mutex during the scan and reacquire it after the
scan. Make sure that purge thread doesn't purge the records of the table
being truncated and background stats collection thread skips the updation
of stats for the table being truncated.

[#rb 14564 Approved by Jimmy and satya ]
This commit is contained in:
Aditya A
2017-01-04 14:34:38 +05:30
committed by Marko Mäkelä
parent 13dcdb0903
commit 62dca454e7
9 changed files with 388 additions and 29 deletions
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124
mysql-test/suite/innodb/r/innodb-truncate-debug.result Normal file
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#
# Bug #23070734 CONCURRENT TRUNCATE TABLES CAUSE STALLS
#
Test_1 :- Check if DDL operations are possible on
table being truncated. Also check if
DDL operations on other tables succeed.
create table t1 (f1 int,f2 int,key(f2),f3 int) engine=innodb;
create index idx1 on t1(f3);
create table t2 (f1 int,f2 int,key(f2),f3 int) engine=innodb;
create table t3 (f1 int,f2 int,key(f2)) engine=innodb;
insert into t1 values (10,20,30),(30,40,50),(50,60,70);
insert into t1 select * from t1;
insert into t1 select * from t1;
insert into t1 select * from t1;
insert into t2 values (10,20,30),(30,40,50),(50,60,70);
insert into t2 select * from t2;
insert into t2 select * from t2;
insert into t2 select * from t2;
insert into t3 values (10,20),(30,40),(50,50);
insert into t3 select * from t3;
insert into t3 select * from t3;
SET session lock_wait_timeout = 1;
show variables like 'lock_wait_timeout%';
Variable_name Value
lock_wait_timeout 1
connection 1
SET DEBUG_SYNC= 'simulate_buffer_pool_scan SIGNAL opened WAIT_FOR finish_scan';
truncate table t1;;
connection default
SET DEBUG_SYNC= 'now WAIT_FOR opened';
Check Analyze table. Gives lock time out error.
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze Error Lock wait timeout exceeded; try restarting transaction
test.t1 analyze status Operation failed
Check if we can turn off auto recalculation.
alter table t1 STATS_AUTO_RECALC=0;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
Check if we can turn off persistent stats on the table
alter table t1 STATS_PERSISTENT=0;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
Check if DML is possible on table being truncated
insert into t1 values (10,89,99);
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
Check if DDL is possible on table being truncated
alter table t1 add column f4 int;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
check if table can be created with the same name
create table t1 (bd int) engine=innodb;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
check if index can be created on table being truncated
create index idx1 on t1(f1);
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
Check if DROP of table is possible during truncate
drop table t1;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
Check if select is possible during truncate
select * from t1;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
select * from t2 where t2.f1=t1.f1;
ERROR 42S22: Unknown column 't1.f1' in 'where clause'
Check concurrent truncate operation on table;
truncate table t1;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
Check concurrent selects and inserts on the other table
insert into t3 values (10,20),(30,40),(50,50);
select * from t3 where f1=40;
f1 f2
Concurrent truncate on other tables
truncate table t2;
Concurrent alters on the other tables
alter table t2 add column f4 int;
check if index can be created on the other table
create index idx1 on t2(f3);
Check if we can turn off persistent stats off entire instance
SET GLOBAL innodb_stats_persistent=off;
connection con2
set global innodb_adaptive_hash_index=off;;
connection default
SET DEBUG_SYNC= 'now SIGNAL finish_scan';
connection con1
connection con2
connection default
SET session lock_wait_timeout=default;
set global innodb_adaptive_hash_index=default;
drop table t1,t2,t3;
SET @@global.innodb_stats_persistent=default;
Test_2 :- Check if purge thread ignores the undo
log records of the table being truncated.
create table t1 (f1 int ,f2 int,key(f2)) engine=innodb;
insert into t1 values (10,45),(20,78),(30,88),(40,23),(50,78),(60,11),(70,56),(80,90);
insert into t1 select * from t1;
insert into t1 select * from t1;
insert into t1 select * from t1;
insert into t1 select * from t1;
insert into t1 select * from t1;
insert into t1 select * from t1;
insert into t1 select * from t1;
insert into t1 select * from t1;
insert into t1 select * from t1;
insert into t1 select * from t1;
insert into t1 select * from t1;
insert into t1 select * from t1;
insert into t1 select * from t1;
insert into t1 select * from t1;
select count(*) from t1;
count(*)
131072
Stop the purge thread
set global innodb_purge_stop_now = 1;
delete from t1;
connection con1
SET DEBUG_SYNC= 'simulate_buffer_pool_scan SIGNAL opened WAIT_FOR finish_scan';
truncate table t1;;
Connection default
SET DEBUG_SYNC= 'now WAIT_FOR opened';
set global innodb_purge_run_now=1;
SET DEBUG_SYNC= 'now SIGNAL finish_scan';
connection con1
connection default
drop table t1;
Pattern "InnoDB: Record with space id \d+ belongs to table which is being truncated therefore skipping this undo record." found
# restart server
# restart: