MySQL Server Variable Tuning
Content
www.fromdual.com
MySQL Performance Tuning
DOAG 2013 Datenbank
14. Mai 2013, Düsseldorf
Oli Sennhauser
Senior MySQL Berater, FromDual GmbH
[email protected]
1 / 24
Über FromDual GmbH
●
●
www.fromdual.com
FromDual bietet neutral und unabhängig:
●
Beratung für MySQL
●
Support für MySQL und Galera Cluster
●
Remote-DBA Dienstleistungen für MySQL
●
MySQL Schulungen
Oracle Silver Partner (OPN)
www.fromdual.com
2 / 24
Inhalt
www.fromdual.com
HA Solutions
MySQL
Performance Tuning mit System-Variablen
➢
➢
➢
➢
➢
➢
➢
➢
➢
➢
➢
Performance
Read
scale-out
Tuning Hebel
Replication
MySQL
System
set-up
Variablen
for HA
Active/passive
MySQL
Status Variablen
fail-over
MySQL Architektur
Cluster
Replication Cluster
Speicherbelegung
Storage-Engine-Replication
Session
Variablen
Globale Variablen
MyISAM Variablen
InnoDB Variablen
Monitoring
Informationen
3 / 24
Performance Tuning Hebel
www.fromdual.com
4 / 24
MySQL System Variablen
●
www.fromdual.com
Datenbank-Konfiguration
my.cnf
mysqld help –verbose
/etc/my.cnf /etc/mysql/my.cnf
/usr/local/mysql/etc/my.cnf
$basedir/my.cnf ~/.my.cnf
SHOW GLOBAL VARIABLES;
5 / 24
MySQL Status Variablen
●
www.fromdual.com
Was wir damit anrichten sieht man mit:
SHOW /*!50001 GLOBAL */ STATUS;
SHOW ENGINE INNODB STATUS\G
6 / 24
MySQL Architektur
www.fromdual.com
Application / Client
Thread
Cache
Connection
Manager
User Authentication
Logging
Command
Dispatcher
Query
Cache
Query Cache
Module
mysqld
Parser
Optimizer
Access Control
Table Manager
Table Open
Cache (.frm, fh)
Table Definition
Cache (tbl def.)
Handler Interface
MyISAM
InnoDB
Memory
NDB
PBXT
Aria
XtraDB
Tokutek
...
7 / 24
Speicherbelegung
Client 1
read_buffer
sort_buffer
Client 2
Client N
read_buffer
read_buffer
sort_buffer
tmp_table
Local Memory Areas
MySQL Server (mysqld)
www.fromdual.com
Storage Engines
key_buffer_size
innodb_buffer_pool_size
innodb_log_buffer_size
etc...
table_open_cache
table_definition_cache
query_cache_size
etc...
Global Memory Area
8 / 24
Thread Cache
●
●
www.fromdual.com
Konifguration:
thread_cache_size
Status:
threads_created
+++
| Variable_name | Value |
+++
| Threads_cached | 8 |
| Threads_connected | 242 |
| Threads_created | 15355 |
| Threads_running | 16 |
+++
9 / 24
Query Cache
www.fromdual.com
●
Konfiguration: query_cache_size
●
Status:
Com_select,
Qcache_hits
●
Hit ratio:
+++
| Variable_name | Value |
+++
| Com_select | 25712 |
| Qcache_free_memory | 19553200 |
| Qcache_hits | 65137 |
| Qcache_inserts | 172167 |
+++
Qache_hits/(Com_select + Qcache_hits)
10 / 24
Per Session Parameter
www.fromdual.com
●
Im „Executor“
●
Alloziert/Dealloziert „on Demand“
●
Per Session oder global einstellbar
●
Meisst Effekt gering oder gar kontraproduktiv!
●
Join Buffer
●
●
join_buffer_size
Read Buffer und Read Random Buffer
●
read_buffer_size, read_rnd_buffer_size
11 / 24
Sort Buffer, temporäre Tabellen
www.fromdual.com
●
Temporäre Tabellen
(MEMORY oder MyISAM)
●
●
●
Konfiguration: tmp_table_size,
(max_heap_table_size)
Status: created_tmp_tables,
created_tmp_disk_tables
Sort Buffer
●
●
Konfiguration:
sort_buffer_size
Status: sort_merge_passes
12 / 24
Table Definition Cache
www.fromdual.com
●
Ab v5.1
●
Enthält Info vom .frm File
●
Konfiguration: table_definition_cache
●
Status: open_table_definitions,
opened_table_defintions
+++
| Variable_name | Value |
+++
| Open_table_definitions | 100 |
| Opened_table_definitions | 100 |
+++
13 / 24
Table (Open) Cache
●
www.fromdual.com
Ab v5.1
●
File-Descriptioren (1 pro Connection pro Table)
●
Früher table_cache
●
Konfiguration: table_open_cache
●
Status: open_tables, opened_tables
+++
| Variable_name | Value |
+++
| Open_tables | 64 |
| Opened_tables | 11812 |
+++
14 / 24
MyISAM
●
Bis MySQL 5.1 default Storage Engine
●
Konfiguration: key_buffer_size
●
www.fromdual.com
Status: Key_blocks_used,
Key_blocks_unused, Key_reads,
Key_read_requests
15 / 24
InnoDB Buffer Pool
adaptive hash idx
OS file cache
async
trx log buffer
innodb_buffer_pool_size,
innodb_buffer_pool_instances,
innodb_io_capacity
index pages
undo records
lock info table
buffer pool
sync
Konfiguration:
data pages
secondary index buffer
ib_logfile1
●
InnoDB Buffer Pool
mysqld
system table space: ibdata1
undo
double write area
ib_logfile2
●
InnoDB seit 5.5 default Storage Engine
ib_logfilen
●
www.fromdual.com
dd
tables/indexes
table table space table table space table table space
16 / 24
InnoDB Buffer Pool
●
www.fromdual.com
Status:
innodb_buffer_pool_pages_%,
Innodb_buffer_bytes_%,
Innodb_data_%
17 / 24
InnoDB Log File
●
Status: innodb%log%
index pages
adaptive hash idx
undo records
lock info table
trx log buffer
OS file cache
async
innodb_flush_log_at_trx
_commit
sync
innodb_log_file_size,
data pages
secondary index buffer
buffer pool
ib_logfile1
Konfiguration:
mysqld
system table space: ibdata1
undo
double write area
ib_logfile2
●
REDO Log, Transaction
Log
ib_logfilen
●
www.fromdual.com
dd
tables/indexes
table table space table table space table table space
18 / 24
Binary Log
Application
www.fromdual.com
Application
mysqld
Application
binlog_cache_size
binlog_stmt_cache_size
sync_binlog
bin-log.n
+++
| Variable_name | Value |
+++
| Binlog_cache_disk_use | 3456 |
| Binlog_cache_use | 12786 |
| Binlog_stmt_cache_disk_use | 0 |
| Binlog_stmt_cache_use | 0 |
+++
19 / 24
Monitoring
●
●
www.fromdual.com
Von Hand:
●
SHOW GLOBAL STATUS;
●
SHOW ENGINE INNODB STATUS\G
●
Performance Schema (P_S, >= v5.5)
Irgend ein graphisches Monitoring Tool...
20 / 24
PERFORMANCE_SCHEMA
●
In Diskussion seit mindestens 2006
●
Eingeführt in MySQL 5.5 (2010)
●
www.fromdual.com
→ Einblick in die Datenbank
In v5.5 disabled, in v5.6 enabled per default
performance_schema = 1
●
Overhead 5% - 200%! → also Vorsicht!
21 / 24
Beispiel: Table I/O waits
www.fromdual.com
SELECT OBJECT_SCHEMA, OBJECT_NAME
, ROUND(SUM_TIMER_WAIT/1000000000, 3) AS SUM_TIMER_WAIT
, ROUND(SUM_TIMER_READ/1000000000, 3) AS SUM_TIMER_READ
, ROUND(SUM_TIMER_WRITE/1000000000, 3) AS SUM_TIMER_WRITE
FROM table_io_waits_summary_by_table
ORDER BY SUM_TIMER_WAIT DESC
LIMIT 10
;
++++++
| OBJECT_SCHEMA | OBJECT_NAME | SUM_TIMER_WAIT | SUM_TIMER_READ | SUM_TIMER_WRITE |
++++++
| zabbix | items | 1182496.258 | 616630.696 | 565865.562 |
| zabbix | history_uint | 889884.116 | 370528.991 | 519355.125 |
| zabbix | history_str | 460411.155 | 246159.458 | 214251.697 |
| zabbix | history | 389815.659 | 86285.980 | 303529.679 |
| zabbix | trends_uint | 133955.560 | 107365.626 | 26589.934 |
| zabbix | functions | 128657.654 | 128657.654 | 0.000 |
| zabbix | trends | 43683.159 | 36314.732 | 7368.428 |
| mpm | mpm_agent | 27837.056 | 27837.056 | 0.000 |
| zabbix | hosts | 23820.284 | 14044.672 | 9775.612 |
| zabbix | triggers | 21052.459 | 20970.604 | 81.855 |
++++++
22 / 24
Informationen
●
www.fromdual.com
MySQL System Variablen:
http://dev.mysql.com/doc/refman/5.5/en/server-system-variables.html
●
MySQL Status Variablen:
http://dev.mysql.com/doc/refman/5.5/en/server-status-variables.html
●
MySQL DB Health Check:
http://www.fromdual.com/mysql-database-health-check
●
MySQL Performance Monitor:
http://www.fromdual.com/mysql-performance-monitor
23 / 24
Q&A
www.fromdual.com
Fragen ?
Diskussion?
Wir haben Zeit für ein Performance Audit...!
●
FromDual bietet neutral und unabhängig:
●
Beratung
●
Remote-DBA
●
Support für MySQL und Galera Cluster
●
Schulung
www.fromdual.com/presentations
24 / 24
MySQL Performance Tuning
DOAG 2013 Datenbank
14. Mai 2013, Düsseldorf
Oli Sennhauser
Senior MySQL Berater, FromDual GmbH
[email protected]
1 / 24
Über FromDual GmbH
●
●
www.fromdual.com
FromDual bietet neutral und unabhängig:
●
Beratung für MySQL
●
Support für MySQL und Galera Cluster
●
Remote-DBA Dienstleistungen für MySQL
●
MySQL Schulungen
Oracle Silver Partner (OPN)
www.fromdual.com
2 / 24
Inhalt
www.fromdual.com
HA Solutions
MySQL
Performance Tuning mit System-Variablen
➢
➢
➢
➢
➢
➢
➢
➢
➢
➢
➢
Performance
Read
scale-out
Tuning Hebel
Replication
MySQL
System
set-up
Variablen
for HA
Active/passive
MySQL
Status Variablen
fail-over
MySQL Architektur
Cluster
Replication Cluster
Speicherbelegung
Storage-Engine-Replication
Session
Variablen
Globale Variablen
MyISAM Variablen
InnoDB Variablen
Monitoring
Informationen
3 / 24
Performance Tuning Hebel
www.fromdual.com
4 / 24
MySQL System Variablen
●
www.fromdual.com
Datenbank-Konfiguration
my.cnf
mysqld help –verbose
/etc/my.cnf /etc/mysql/my.cnf
/usr/local/mysql/etc/my.cnf
$basedir/my.cnf ~/.my.cnf
SHOW GLOBAL VARIABLES;
5 / 24
MySQL Status Variablen
●
www.fromdual.com
Was wir damit anrichten sieht man mit:
SHOW /*!50001 GLOBAL */ STATUS;
SHOW ENGINE INNODB STATUS\G
6 / 24
MySQL Architektur
www.fromdual.com
Application / Client
Thread
Cache
Connection
Manager
User Authentication
Logging
Command
Dispatcher
Query
Cache
Query Cache
Module
mysqld
Parser
Optimizer
Access Control
Table Manager
Table Open
Cache (.frm, fh)
Table Definition
Cache (tbl def.)
Handler Interface
MyISAM
InnoDB
Memory
NDB
PBXT
Aria
XtraDB
Tokutek
...
7 / 24
Speicherbelegung
Client 1
read_buffer
sort_buffer
Client 2
Client N
read_buffer
read_buffer
sort_buffer
tmp_table
Local Memory Areas
MySQL Server (mysqld)
www.fromdual.com
Storage Engines
key_buffer_size
innodb_buffer_pool_size
innodb_log_buffer_size
etc...
table_open_cache
table_definition_cache
query_cache_size
etc...
Global Memory Area
8 / 24
Thread Cache
●
●
www.fromdual.com
Konifguration:
thread_cache_size
Status:
threads_created
+++
| Variable_name | Value |
+++
| Threads_cached | 8 |
| Threads_connected | 242 |
| Threads_created | 15355 |
| Threads_running | 16 |
+++
9 / 24
Query Cache
www.fromdual.com
●
Konfiguration: query_cache_size
●
Status:
Com_select,
Qcache_hits
●
Hit ratio:
+++
| Variable_name | Value |
+++
| Com_select | 25712 |
| Qcache_free_memory | 19553200 |
| Qcache_hits | 65137 |
| Qcache_inserts | 172167 |
+++
Qache_hits/(Com_select + Qcache_hits)
10 / 24
Per Session Parameter
www.fromdual.com
●
Im „Executor“
●
Alloziert/Dealloziert „on Demand“
●
Per Session oder global einstellbar
●
Meisst Effekt gering oder gar kontraproduktiv!
●
Join Buffer
●
●
join_buffer_size
Read Buffer und Read Random Buffer
●
read_buffer_size, read_rnd_buffer_size
11 / 24
Sort Buffer, temporäre Tabellen
www.fromdual.com
●
Temporäre Tabellen
(MEMORY oder MyISAM)
●
●
●
Konfiguration: tmp_table_size,
(max_heap_table_size)
Status: created_tmp_tables,
created_tmp_disk_tables
Sort Buffer
●
●
Konfiguration:
sort_buffer_size
Status: sort_merge_passes
12 / 24
Table Definition Cache
www.fromdual.com
●
Ab v5.1
●
Enthält Info vom .frm File
●
Konfiguration: table_definition_cache
●
Status: open_table_definitions,
opened_table_defintions
+++
| Variable_name | Value |
+++
| Open_table_definitions | 100 |
| Opened_table_definitions | 100 |
+++
13 / 24
Table (Open) Cache
●
www.fromdual.com
Ab v5.1
●
File-Descriptioren (1 pro Connection pro Table)
●
Früher table_cache
●
Konfiguration: table_open_cache
●
Status: open_tables, opened_tables
+++
| Variable_name | Value |
+++
| Open_tables | 64 |
| Opened_tables | 11812 |
+++
14 / 24
MyISAM
●
Bis MySQL 5.1 default Storage Engine
●
Konfiguration: key_buffer_size
●
www.fromdual.com
Status: Key_blocks_used,
Key_blocks_unused, Key_reads,
Key_read_requests
15 / 24
InnoDB Buffer Pool
adaptive hash idx
OS file cache
async
trx log buffer
innodb_buffer_pool_size,
innodb_buffer_pool_instances,
innodb_io_capacity
index pages
undo records
lock info table
buffer pool
sync
Konfiguration:
data pages
secondary index buffer
ib_logfile1
●
InnoDB Buffer Pool
mysqld
system table space: ibdata1
undo
double write area
ib_logfile2
●
InnoDB seit 5.5 default Storage Engine
ib_logfilen
●
www.fromdual.com
dd
tables/indexes
table table space table table space table table space
16 / 24
InnoDB Buffer Pool
●
www.fromdual.com
Status:
innodb_buffer_pool_pages_%,
Innodb_buffer_bytes_%,
Innodb_data_%
17 / 24
InnoDB Log File
●
Status: innodb%log%
index pages
adaptive hash idx
undo records
lock info table
trx log buffer
OS file cache
async
innodb_flush_log_at_trx
_commit
sync
innodb_log_file_size,
data pages
secondary index buffer
buffer pool
ib_logfile1
Konfiguration:
mysqld
system table space: ibdata1
undo
double write area
ib_logfile2
●
REDO Log, Transaction
Log
ib_logfilen
●
www.fromdual.com
dd
tables/indexes
table table space table table space table table space
18 / 24
Binary Log
Application
www.fromdual.com
Application
mysqld
Application
binlog_cache_size
binlog_stmt_cache_size
sync_binlog
bin-log.n
+++
| Variable_name | Value |
+++
| Binlog_cache_disk_use | 3456 |
| Binlog_cache_use | 12786 |
| Binlog_stmt_cache_disk_use | 0 |
| Binlog_stmt_cache_use | 0 |
+++
19 / 24
Monitoring
●
●
www.fromdual.com
Von Hand:
●
SHOW GLOBAL STATUS;
●
SHOW ENGINE INNODB STATUS\G
●
Performance Schema (P_S, >= v5.5)
Irgend ein graphisches Monitoring Tool...
20 / 24
PERFORMANCE_SCHEMA
●
In Diskussion seit mindestens 2006
●
Eingeführt in MySQL 5.5 (2010)
●
www.fromdual.com
→ Einblick in die Datenbank
In v5.5 disabled, in v5.6 enabled per default
performance_schema = 1
●
Overhead 5% - 200%! → also Vorsicht!
21 / 24
Beispiel: Table I/O waits
www.fromdual.com
SELECT OBJECT_SCHEMA, OBJECT_NAME
, ROUND(SUM_TIMER_WAIT/1000000000, 3) AS SUM_TIMER_WAIT
, ROUND(SUM_TIMER_READ/1000000000, 3) AS SUM_TIMER_READ
, ROUND(SUM_TIMER_WRITE/1000000000, 3) AS SUM_TIMER_WRITE
FROM table_io_waits_summary_by_table
ORDER BY SUM_TIMER_WAIT DESC
LIMIT 10
;
++++++
| OBJECT_SCHEMA | OBJECT_NAME | SUM_TIMER_WAIT | SUM_TIMER_READ | SUM_TIMER_WRITE |
++++++
| zabbix | items | 1182496.258 | 616630.696 | 565865.562 |
| zabbix | history_uint | 889884.116 | 370528.991 | 519355.125 |
| zabbix | history_str | 460411.155 | 246159.458 | 214251.697 |
| zabbix | history | 389815.659 | 86285.980 | 303529.679 |
| zabbix | trends_uint | 133955.560 | 107365.626 | 26589.934 |
| zabbix | functions | 128657.654 | 128657.654 | 0.000 |
| zabbix | trends | 43683.159 | 36314.732 | 7368.428 |
| mpm | mpm_agent | 27837.056 | 27837.056 | 0.000 |
| zabbix | hosts | 23820.284 | 14044.672 | 9775.612 |
| zabbix | triggers | 21052.459 | 20970.604 | 81.855 |
++++++
22 / 24
Informationen
●
www.fromdual.com
MySQL System Variablen:
http://dev.mysql.com/doc/refman/5.5/en/server-system-variables.html
●
MySQL Status Variablen:
http://dev.mysql.com/doc/refman/5.5/en/server-status-variables.html
●
MySQL DB Health Check:
http://www.fromdual.com/mysql-database-health-check
●
MySQL Performance Monitor:
http://www.fromdual.com/mysql-performance-monitor
23 / 24
Q&A
www.fromdual.com
Fragen ?
Diskussion?
Wir haben Zeit für ein Performance Audit...!
●
FromDual bietet neutral und unabhängig:
●
Beratung
●
Remote-DBA
●
Support für MySQL und Galera Cluster
●
Schulung
www.fromdual.com/presentations
24 / 24
