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MDEV-9101 Limit size of created disk temporary files and tables

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Two new variables added:
- max_tmp_space_usage : Limits the the temporary space allowance per user
- max_total_tmp_space_usage: Limits the temporary space allowance for
  all users.

New status variables: tmp_space_used & max_tmp_space_used
New field in information_schema.process_list: TMP_SPACE_USED

The temporary space is counted for:
- All SQL level temporary files. This includes files for filesort,
  transaction temporary space, analyze, binlog_stmt_cache etc.
  It does not include engine internal temporary files used for repair,
  alter table, index pre sorting etc.
- All internal on disk temporary tables created as part of resolving a
  SELECT, multi-source update etc.

Special cases:
- When doing a commit, the last flush of the binlog_stmt_cache
  will not cause an error even if the temporary space limit is exceeded.
  This is to avoid giving errors on commit. This means that a user
  can temporary go over the limit with up to binlog_stmt_cache_size.

Noteworthy issue:
- One has to be careful when using small values for max_tmp_space_limit
  together with binary logging and with non transactional tables.
  If a the binary log entry for the query is bigger than
  binlog_stmt_cache_size and one hits the limit of max_tmp_space_limit
  when flushing the entry to disk, the query will abort and the
  binary log will not contain the last changes to the table.
  This will also stop the slave!
  This is also true for all Aria tables as Aria cannot do rollback
  (except in case of crashes)!
  One way to avoid it is to use @@binlog_format=statement for
  queries that updates a lot of rows.

Implementation:
- All writes to temporary files or internal temporary tables, that
  increases the file size, are routed through temp_file_size_cb_func()
  which updates and checks the temp space usage.
- Most of the temporary file monitoring is done inside IO_CACHE.
  Temporary file monitoring is done inside the Aria engine.
- MY_TRACK and MY_TRACK_WITH_LIMIT are new flags for ini_io_cache().
  MY_TRACK means that we track the file usage. TRACK_WITH_LIMIT means
  that we track the file usage and we give an error if the limit is
  breached. This is used to not give an error on commit when
  binlog_stmp_cache is flushed.
- global_tmp_space_used contains the total tmp space used so far.
  This is needed quickly check against max_total_tmp_space_usage.
- Temporary space errors are using EE_LOCAL_TMP_SPACE_FULL and
  handler errors are using HA_ERR_LOCAL_TMP_SPACE_FULL.
  This is needed until we move general errors to it's own error space
  so that they cannot conflict with system error numbers.
- Return value of my_chsize() and mysql_file_chsize() has changed
  so that -1 is returned in the case my_chsize() could not decrease
  the file size (very unlikely and will not happen on modern systems).
  All calls to _chsize() are updated to check for > 0 as the error
  condition.
- At the destruction of THD we check that THD::tmp_file_space == 0
- At server end we check that global_tmp_space_used == 0
- As a precaution against errors in the tmp_space_used code, one can set
  max_tmp_space_usage and max_total_tmp_space_usage to 0 to disable
  the tmp space quota errors.
- truncate_io_cache() function added.
- Aria tables using static or dynamic row length are registered in 8K
  increments to avoid some calls to update_tmp_file_size().

Other things:
- Ensure that all handler errors are registered.  Before, some engine
  errors could be printed as "Unknown error".
- Fixed bug in filesort() that causes a assert if there was an error
  when writing to the temporay file.
- Fixed that compute_window_func() now takes into account write errors.
- In case of parallel replication, rpl_group_info::cleanup_context()
  could call trans_rollback() with thd->error set, which would cause
  an assert. Fixed by resetting the error before calling trans_rollback().
- Fixed bug in subselect3.inc which caused following test to use
  heap tables with low value for max_heap_table_size
- Fixed bug in sql_expression_cache where it did not overflow
  heap table to Aria table.
- Added Max_tmp_disk_space_used to slow query log.
- Fixed some bugs in log_slow_innodb.test
This commit is contained in:
Monty
2024-03-14 17:59:00 +01:00
committed by Sergei Golubchik
parent b60419e0e4
commit b9f5793176
77 changed files with 1373 additions and 380 deletions
Download Patch File Download Diff File Expand all files Collapse all files

153
mysql-test/main/tmp_space_usage.result Normal file
View File

@ -0,0 +1,153 @@
call mtr.add_suppression("Write to binary log failed: .* temporary space limit reached. An incident event is written to binary log.*");
flush status;
flush global status;
show session status like "max_tmp_space_used";
Variable_name Value
Max_tmp_space_used 0
show global status like "max_tmp_space_used";
Variable_name Value
Max_tmp_space_used 0
#
# MDEV-9101 Limit size of total size of created disk temporary files
# and tables.
show session status like "tmp_space_used";
Variable_name Value
Tmp_space_used 0
show global status like "tmp_space_used";
Variable_name Value
Tmp_space_used 0
select @@global.max_tmp_session_space_usage, @@global.max_tmp_total_space_usage;
@@global.max_tmp_session_space_usage @@global.max_tmp_total_space_usage
524288 786432
select @@binlog_stmt_cache_size,@@binlog_format;
@@binlog_stmt_cache_size @@binlog_format
32768 ROW
create table t1 (a int primary key, v varchar(256), c int default(0)) engine=innodb;
insert into t1 (a,v) select seq, repeat(char(64+mod(seq,32)),mod(seq,254)+1) from seq_1_to_65536;
ERROR HY000: Local temporary space limit reached
set @@max_tmp_session_space_usage=1024*1024*1024;
insert into t1 (a,v) select seq, repeat(char(64+mod(seq,32)),mod(seq,254)+1) from seq_1_to_65536;
ERROR HY000: Global temporary space limit reached
set @@max_tmp_session_space_usage=default;
set @@binlog_format="statement";
insert into t1 (a,v) select seq, repeat(char(64+mod(seq,32)),mod(seq,254)+1) from seq_1_to_65536;
insert into t1 (a,v) select seq, repeat(char(64+mod(seq,32)),mod(seq,254)+1) from seq_65537_to_131072;
select count(*) from t1;
count(*)
131072
create table t2 (a int, b int) engine=innodb select seq as a, 0 as b from seq_1_to_131072;
set @@binlog_format="row";
set @@tmp_memory_table_size=32*1024;
# The following queries should fail because of tmp_space_usage
select * from t1 order by a,v;
ERROR HY000: Local temporary space limit reached
select v,count(*) from t1 group by v limit 2;
ERROR HY000: Local temporary space limit reached
update t1 set v=right(v,2);
ERROR HY000: Local temporary space limit reached
set @@binlog_format="statement";
set @@max_tmp_session_space_usage=65536;
set @@tmp_memory_table_size=0;
update t1,t2 set t1.c=t2.a, t2.b=1 where t1.a=t2.a;
ERROR HY000: Local temporary space limit reached
set @@binlog_format="row";
set @@max_tmp_session_space_usage=default;
drop table t1,t2;
#
# Check max_tmp_total_space_usage & processlist
#
set @@tmp_memory_table_size=1024*1024;
show session status like "tmp_space_used";
Variable_name Value
Tmp_space_used 0
set @@tmp_memory_table_size=0;
flush status;
# session.max_tmp_session_space_usage == global.max_tmp_session_space_usage
connect c1, localhost, root,,;
connection default;
create table t1 (a int primary key, v varchar(256), c int default(0)) engine=innodb;
create table t2 (a int primary key, v varchar(256), c int default(0)) engine=innodb;
begin;
insert into t1 (a,v) select seq, repeat(char(64+mod(seq,32)),mod(seq,254)+1) from seq_1_to_3000;
connection c1;
# information_schema.process_list.tmp_space_used == status.tmp_space_used
insert into t2 (a,v) select seq, repeat(char(64+mod(seq,32)),mod(seq,254)+1) from seq_1_to_3000;
ERROR HY000: Global temporary space limit reached
# Test setting tmp_space_usage to 0 to disable quotas
set @save_max_tmp_total_space_usage=@@global.max_tmp_total_space_usage;
set @@global.max_tmp_total_space_usage=0;
set @@max_tmp_session_space_usage=0;
insert into t2 (a,v) select seq, repeat(char(64+mod(seq,32)),mod(seq,254)+1) from seq_1_to_3000;
set @@global.max_tmp_total_space_usage=@save_max_tmp_total_space_usage;
set @@max_tmp_session_space_usage=0;
connection default;
insert into t1 (a,v) values(9999990,0);
commit;
select count(*) from t1;
count(*)
3001
disconnect c1;
drop table t1,t2;
#
# Test case from Elena
#
SET @@max_tmp_session_space_usage= 64*1024;
set @@binlog_format="statement";
CREATE OR REPLACE TABLE t1 (a INT, b INT);
select benchmark(1,1);
benchmark(1,1)
0
INSERT INTO t1 SELECT seq, seq FROM seq_1_to_100000;
ALTER TABLE t1 ORDER BY a, b;
ERROR HY000: Local temporary space limit reached
DROP TABLE t1;
#
# Show that setting max tmp space too low value can stop binary logging
# if non transactional tables are used.
#
set @save_max_tmp_total_space_usage=@@global.max_tmp_total_space_usage;
SET @@global.max_tmp_total_space_usage=64*1024;
set @@binlog_format="row";
create table t1 (a int primary key, v varchar(256)) engine=myisam;
insert into t1 (a,v) select seq, repeat(char(64+mod(seq,32)),mod(seq,254)+1) from seq_1_to_65536;
Got one of the listed errors
show warnings;
Level Code Message
Error 42 Global temporary space limit reached
Error 1534 Writing one row to the row-based binary log failed
Warning 1196 Some non-transactional changed tables couldn't be rolled back
select count(*) <> 0 from t1;
count(*) <> 0
1
truncate table t1;
alter table t1 engine=innodb;
insert into t1 (a,v) select seq, repeat(char(64+mod(seq,32)),mod(seq,254)+1) from seq_1_to_65536;
Got one of the listed errors
show warnings;
Level Code Message
Error 42 Global temporary space limit reached
Error 1534 Writing one row to the row-based binary log failed
select count(*) <> 0 from t1;
count(*) <> 0
0
drop table t1;
set @@global.max_tmp_total_space_usage=@save_max_tmp_total_space_usage;
#
# Check updating non transactional table
#
SET max_tmp_session_space_usage= 64*1024;
CREATE TABLE t1 (
a varchar(1024), b varchar(1024), c varchar(1024), d varchar(1024), e varchar(1024), f varchar(1024), g varchar(1024)
) ENGINE=MyISAM;
INSERT INTO t1 VALUES
(REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024)),
(REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024)),
(REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024)),
(REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024)),
(REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024)),
(REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024),REPEAT('x',1024)),
('x','x','x','x','x','x','x');
UPDATE t1 SET a = '' LIMIT 100;
ERROR HY000: Local temporary space limit reached
DROP TABLE t1;
# End of 11.5 tests