介绍 Percona 服务器 XtraDB 和 Xtrabackup

Introduction to Percona Server, XtraDB and Xtrabackup Morgan Tocker morgan@percona.com

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Who is Percona?

CONSULTING

SUPPORT

TRAINING

MAINTENANCE

.. for MySQL.

2

Who is Percona?

CONSULTING

SUPPORT

TRAINING

MAINTENANCE

.. for MySQL.

2

Who is Percona?

CONSULTING

SUPPORT

TRAINING

MAINTENANCE

.. for MySQL.

2

Who is Percona?

CONSULTING

SUPPORT

TRAINING

MAINTENANCE

.. for MySQL.

2

Who is Percona?

CONSULTING

SUPPORT

TRAINING

MAINTENANCE

.. for MySQL.

2

Today’s Agenda ★ ★ ★ ★ ★

3

Percona products at 10 000 feet.

A closer look at Percona Server with XtraDB. A closer look at XtraBackup.

A quick look into the future.

Finding more information.

Percona Server?

4

Official Oracle Product

License

MySQL Server

GPL/Commercial

The InnoDB Storage Engine (Plugin edition)

GPL/Commercial

InnoDB Hot Backup

Commercial

Official Percona Product

License

Percona Server

GPL

The XtraDB Storage Engine

GPL

XtraBackup

GPL

Percona Server is... ★

A Percona sponsored distribution of the MySQL Server. ✦

✦

★

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Current releases are based on MySQL 5.1.

Earlier releases based on MySQL 5.0 are available.

Contains all of the great work of the MySQL engineering team + additional enhancements on top.

XtraDB is.. ★

An enhanced version of the InnoDB storage engine. ✦

✦

★

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We ship Percona Server 5.1 with XtraDB included.

You don’t have to download it separately, or do anything special to enable it.

XtraDB is based on the “InnoDB plugin”.

XtraBackup is... ★ ★

★

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An re-implementation of InnoDB’s hot backup utility.

XtraBackup can backup MyISAM, Archive and InnoDB tables.

It can backup MySQL, Percona and MariaDB servers.

A fork or a spoon? ★

Percona Server and XtraDB are forks by definition. ✦

★

Don’t let the word fork scare you. ✦

✦

✦

✦

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We change the name to help users identify our distinctively different set of features. ~30K lines changed out of millions.

We rebase off newer official MySQL releases.

License remains as GPL (Open Source).

Compatibility is maintained.

A word on compatibility: ★

★

The file format between MySQL with InnoDB to Percona Server with XtraDB does not change.* XtraDB identifies itself as InnoDB: ✦

★

If you want to revert back, just remove the Percona Packages and install MySQL packages. ✦

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ALTER TABLE my_table ENGINE=INNODB; or CREATE TABLE my_table (a INT) ENGINE=INNODB; still works!

Both Debian/Red Hat packages don’t remove the data directory when you remove the programs.

* By default. You must explicitly enable features for incompatibility.

Compatibility (cont.) ★

★ ★

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When you connect from your PHP/Python/Perl/C/C++/ Ruby/.NET/<insert other language> application to Percona Server, you do not need to make any special changes.

Your application just sees “MySQL” on port 3306.

Really, nothing here changes.

Today’s Agenda ★ ★ ★ ★ ★

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Percona products at 10 000 feet.

A closer look at Percona Server with XtraDB. A closer look at XtraBackup.

A quick look into the future.

Finding more information.

Release Model Safe high value changes, made to market fast.

★

✦

✦

Short release cycle.

Changes are mostly incremental enhancements.

Rebases against new MySQL releases.

★

✦

i.e. Version number should be reads as: Percona-Server-server-51-5.1.52-rel11.6.140.rhel5.x86_64.rpm

Major MySQL Version (MySQL 5.1)

XtraDB Release Version (Release 11.6) Minor MySQL Version (MySQL 5.1.52)

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Releases History ★

Historical average of a new release every 2 months: Release-1

Dec 2008

Release-10.1

May 2010

Release-2

Dec 2008

Release-11.0*

June 2010

Release-3

Feb 2009

Release-11.1

June 2010

Release-4

April 2009

Release-11.2

July 2010

Release-5

April 2009

Release-11.3

September 2010

Release-6

July 2009

Release-12.0

September 2010

Release-7

August 2009

Release-11.4

October 2010

Release-8

Oct 2009

Release-12.1

October 2010

Release-9

Jan 2010

Release-11.5

October 2010

Release-9.1

March 2010

Release-11.6

November 2010

Release-10

April 2010

13 * Recalled Release. The 12.1 branch is now ‘Release Candidate’.

So what changes? ★

Most of the enhancements fall into two categories: ✦

✦

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Performance Improvements Operational / Usability Features

Performance Improvements Improved Buffer Pool Scalability

Separate location of double write buffer*

Improved IO Path + adaptive checkpointing

Transaction logs larger than 4G supported.

Remove excess fcntl calls

Faster Crash Recovery Insert buffer controls Separate purge thread Completely disable the query cache.

Faster page checksums*

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Strip comments before using query cache

Data dictionary memory consumption controls Support for different page sizes*

Improved Rollback Segment Scalability*

Increased number of undo slots* Per session configuration of innodb_flush_log_at_trx_commit

* Changes on disk format. Must use mysqldump to revert to regular MySQL releases.

It’s not all raw performance ★

Many people get carried away with performance. ✦

✦

An earlier benchmark showing Performance of XtraDB 9.x versus regular MySQL releases. Higher is better.

Newer benchmarks are available at http://www.percona.com/ software/benchmarks/

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Consistency of timing is also more important than raw throughput.

Without diagnostics, you won’t get what you are entitled to.

Stability of results â&#x2DC;&#x2026;

â&#x2DC;&#x2026;

Benchmarks is available at http://www.percona.com/software/benchmarks/

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A lot of engineering work has been done to minimize variance.

Sharp drops in MySQL releases are caused by checkpointing activities.

Usability Enhancements Show data dictionary Show contents of the buffer pool Save index statistics between restarts Import / export of buffer pool contents

Store buffer pool in shared memory segment

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Bug fixes - ahead User / Index / Table statistics of time

Log connection errors Import / export of innodb_file_per_table tables

Transactional Replication

Deadlock counter Retain query response time distribution.

Disable automatic statistics regeneration

Advise in processlist when waiting on Query cache mutex.

Better handling of corrupted tables

Improved slow query log

Show Temporary Tables

The slow query log $ tail /var/log/mysql.slow ..

MySQL Server # Time: 100924 13:58:47 # User@Host: root[root] @ localhost [] # Query_time: 399.563977 Lock_time: 0.000110 Rows_sent: 1 Rows_examined: 46313608 SET timestamp=1285336727; select STRAIGHT_JOIN count(*) as c, person_id FROM cast_info FORCE INDEX(person_id) INNER JOIN title ON (cast_info.movie_id=title.id) WHERE title.kind_id = 1 GROUP BY cast_info.person_id ORDER by c DESC LIMIT 1;

$ mysql -e “SET GLOBAL log_slow_verbosity = ‘full’;” Percona Server $ tail /var/log/mysql.slow .. # Time: 100924 13:58:47 # User@Host: root[root] @ localhost [] # Thread_id: 10 Schema: imdb Last_errno: 0 Killed: 0 # Query_time: 399.563977 Lock_time: 0.000110 Rows_sent: 1 Rows_examined: 46313608 Rows_affected: 0 Rows_read: 1 # Bytes_sent: 131 Tmp_tables: 1 Tmp_disk_tables: 1 Tmp_table_sizes: 25194923 # InnoDB_trx_id: 1403 # QC_Hit: No Full_scan: Yes Full_join: No Tmp_table: Yes Tmp_table_on_disk: Yes # Filesort: Yes Filesort_on_disk: Yes Merge_passes: 5 # InnoDB_IO_r_ops: 1064749 InnoDB_IO_r_bytes: 17444847616 InnoDB_IO_r_wait: 26.935662 # InnoDB_rec_lock_wait: 0.000000 InnoDB_queue_wait: 0.000000 # InnoDB_pages_distinct: 65329 SET timestamp=1285336727; select STRAIGHT_JOIN count(*) as c, person_id FROM cast_info FORCE INDEX(person_id) INNER JOIN title ON (cast_info.movie_id=title.id) WHERE title.kind_id = 1 GROUP BY cast_info.person_id ORDER by c DESC LIMIT 1;

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Slow log (cont.) ★

In XtraDB 12.1, this is even further enhanced:

$ mysql -e “SET GLOBAL profiling_server = 1”; $ tail /var/log/mysql.slow .. # Query_time: 4.555235 Lock_time: 0.000000 Rows_sent: 1 Rows_examined: 0 Rows_affected: 0 Rows_read: 1 # Profile_starting: 4.554799 Profile_starting_cpu: 0.000000 Profile_checking_permissions: 0.000095 Profile_checking_permissions_cpu: 0.000000 Profile_Opening_tables: 0.000088 Profile_Opening_tables_cpu: 0.000000 Profile_init: 0.000056 Profile_init_cpu: 0.000000 Profile_optimizing: 0.000046 Profile_optimizing_cpu: 0.000000 Profile_executing: 0.000098 Profile_executing_cpu: 0.000000 Profile_end: 0.000049 Profile_end_cpu: 0.000000 Profile_query_end: 0.000045 Profile_query_end_cpu: 0.000000 Profile_freeing_items: 0.000084 Profile_freeing_items_cpu: 0.000000 Profile_logging_slow_query: 0.000045 Profile_logging_slow_query_cpu: 0.000000 # Profile_total: 4.555405 Profile_total_cpu: 0.000000 insert into teee4 select * from teee4 limit 10000000;

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Find indexes not being used ( Not Possible )

MySQL Server

mysql> SET GLOBAL userstat_running = 1; Percona mysql> SELECT DISTINCT s.TABLE_SCHEMA, s.TABLE_NAME, s.INDEX_NAME FROM information_schema.statistics `s` LEFT JOIN information_schema.index_statistics IS ON (s.TABLE_SCHEMA = IS.TABLE_SCHEMA AND s.TABLE_NAME=IS.TABLE_NAME AND s.INDEX_NAME=IS.INDEX_NAME) WHERE IS.TABLE_SCHEMA IS NULL; +--------------+---------------------------+-----------------+ | TABLE_SCHEMA | TABLE_NAME | INDEX_NAME | +--------------+---------------------------+-----------------+ | art100 | article100 | ext_key | | art100 | article100 | site_id | | art100 | article100 | hash | | art100 | article100 | forum_id_2 | | art100 | article100 | published | | art100 | article100 | inserted | | art100 | article100 | site_id_2 | | art100 | author100 | PRIMARY | | art100 | author100 | site_id | ... +--------------+---------------------------+-----------------+ 1150 rows IN SET (1 min 44.23 sec)

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Server

Usability (cont.) ★

★

Internal locking on the query cache is a major problem on multi-core servers.

Wonder if you’re waiting on the Query Cache? ✦

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We have a new SHOW PROCESSLIST state.

Show Buffer Pool Contents mysql> SELECT d.*,round(100*cnt*16384/(data_length+index_length),2) fit FROM (SELECT schema_name,table_name,count(*) cnt,sum(dirty),sum(hashed) FROM INNODB_BUFFER_POOL_PAGES_INDEX GROUP BY schema_name,table_name ORDER BY cnt DESC LIMIT 20) d JOIN TABLES ON (TABLES.table_schema=d.schema_name AND TABLES.table_name=d.table_name); +-------------+---------------------+---------+------------+-------------+--------+ | schema_name | table_name | cnt | sum(dirty) | sum(hashed) | fit | +-------------+---------------------+---------+------------+-------------+--------+ | db | table1 | 1699133 | 13296 | 385841 | 87.49 | | db | table2 | 1173272 | 17399 | 11099 | 98.42 | | db | table3 | 916641 | 7849 | 15316 | 94.77 | | db | table4 | 86999 | 1555 | 75554 | 87.42 | | db | table5 | 32701 | 7997 | 30082 | 91.61 | | db | table6 | 31990 | 4495 | 25681 | 102.97 | | db | table7 | 1 | 0 | 0 | 100.00 | +-------------+---------------------+---------+------------+-------------+--------+ 7 rows in set (26.45 sec)

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Source: http://www.mysqlperformanceblog.com/ 2010/03/26/tables-fit-buffer-poo/

Save Buffer Pool Contents ★

Export the contents of the buffer pool to a file called ‘ib_lru_dump’ in the data directory: ✦

★

Restored ib_lru_dump: ✦

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SELECT * FROM information_schema.XTRADB_ADMIN_COMMAND /*!

XTRA_LRU_DUMP*/; SELECT * FROM information_schema.XTRADB_ADMIN_COMMAND /*!

XTRA_LRU_RESTORE*/;

Note: Not the actual contents - it takes 8 bytes to remember the address of a 16K page.

To summarize ★

Many MySQL users are not getting the performance they are entitled to. ✦

✦

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They lack visibility into internal operations of MySQL. Giving a 50% improvement through new features sounds nice. What they don’t realize is they’re losing 100% by not being aware.

Today’s Agenda ★ ★ ★ ★ ★

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Percona products at 10 000 feet.

A closer look at Percona Server with XtraDB. A closer look at XtraBackup.

A quick look into the future.

Finding more information.

Backup Overview in MySQL Popular for small databases.

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Best choice when all InnoDB

Popular for databases with MyISAM

mysqldump

mysqldump

Filesystem Snapshot (LVM)

XtraBackup /InnoDB Hot Backup

XtraBackup /InnoDB Hot Backup

MySQLHotc opy

Cold Backup

Engines

InnoDB

ALL

ALL

INNODB

ALL

MyISAM

ALL

Warmth

HOT

WARM

MOSTLY HOT

HOT

WARM

WARM

COLD

Flexibility of Backup

ROW

ROW

SYSTEM

TABLE

TABLE

TABLE

SYSTEM

Flexibility of Restore

MOST

MOST

SYSTEM

TABLE

TABLE

TABLE

SYSTEM

Backup Time

MED

MED

SLOW-MED

FAST

FAST

FAST

BEST

Restore Time

WORST

WORST

BEST

BEST

BEST

BEST

BEST

Impact of Backup

HIGH

HIGH

HIGH

LOW

LOW

MED

N/A

Binary log Coordination

YES

YES

YES

YES

YES

YES

YES

What’s the difference between..?

Filesystem Snapshot (LVM)

XtraBackup/ InnoDB Hot Backup

Engines

ALL

INNODB

Warmth

MOSTLY HOT

HOT

Flexibility of Backup

SYSTEM

TABLE

Flexibility of Restore

SYSTEM

TABLE

Backup Time

SLOW-MED

FAST

Restore Time

BEST

BEST

Impact of Backup

HIGH

LOW

Binary log Coordination

YES

YES

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★

Performance when in snapshot mode with LVM on Linux is much worse. ✦

If your off-peak load is not six times less than your peak load, this may result in a need to over-provision.

See: http://www.mysqlperformanceblog.com/2009/02/05/ disaster-lvm-performance-in-snapshot-mode/

But you said...

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mysqldump

XtraBackup /InnoDB Hot Backup

Engines

InnoDB

INNODB

Warmth

HOT

HOT

Flexibility of Backup

ROW

TABLE

Flexibility of Restore

MOST

TABLE

Backup Time

MED

FAST

Restore Time

WORST

BEST

Impact of Backup

HIGH

LOW

Binary log Coordination

YES

YES

★

★

Mysqldump may be faster in a few cases.

Concern yourself more with recovery time and impact.

http://www.mysqlperformanceblog.com/2010/11/08/anargument-for-not-using-mysqldump-in-production/

XtraBackup is... ★

The best option when you have a considerable amount of data: ✦

✦

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Restore is as simple as moving the backup to your datadir.

It causes the least impact while creating the backup - and is only blocking while backing up MyISAM tables.

InnoDB Hot Backup (1) Percona XtraBackup

MySQL Enterprise Backup (InnoDB Hot Backup)

License

GPL

Proprietary

Price

Free

$5000 per server

Open source

YES

NO

Non-blocking

YES

YES

InnoDB backups

YES

YES

MyISAM backups

YES

YES

Compressed backups

YES

YES

Partial backups

YES

YES

Throttling

YES

YES

Point-in-time recovery support

YES

YES

Incremental backups

YES

YES

Feature

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More Information: http://www.percona.com/software/percona-xtrabackup/

InnoDB Hot Backup (2) Percona XtraBackup

MySQL Enterprise Backup (InnoDB Hot Backup)

Streaming backups

YES

NO

OS buffer optimizations

YES

NO

Export individual tables

YES

NO

Restore tables to a different server

YES

NO

Analyze data & index files

YES

NO

Familiar command-line behavior

YES

NO

Feature

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More Information: http://www.percona.com/software/percona-xtrabackup/

Advanced Features ★

XtraBackup supports some advanced backup options: ✦

✦

✦

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Backup to a stream (can be copied straight across the network, or fed through a compression program).

Throttle to only a limited number of IOPS. Incremental backup.*

* Some special restrictions apply.

Data Definition must not have changed since last backup.

Advanced Features (cont.) â&#x2DC;&#x2026; â&#x2DC;&#x2026;

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Report on fragmentation of indexes: $ xtrabackup --stats --tables=art.link* -datadir=/mnt/data/mysql/ ... table: art/link_out104, index: PRIMARY, space id: 12, root page 3 leaf pages: recs=25958413, pages=497839, data=7492026403 bytes, data/pages=91% ...

http://www.mysqlperformanceblog.com/2009/09/14/statisticsof-innodb-tables-and-indexes-available-in-xtrabackup/

Today’s Agenda ★ ★ ★ ★ ★

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Percona products at 10 000 feet.

A closer look at Percona Server with XtraDB. A closer look at XtraBackup.

A quick look into the future.

Finding more information.

MySQL 5.5 ★ ★

In Release Candidate now.

An awesome release! ✦

✦

★

Percona Server will rebase against 5.5. ✦

✦

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A greatly improved focus on performance.

Some additional diagnostic/usability features.

Work has already began porting features.

We will continue to maintain our 5.1 series.

Percona Server Plans ★

★

Our Blueprints are publicly available through LaunchPad: https://blueprints.launchpad.net/percona-server Percona Server with XtraDB R12.1 is now a release candidate. ✦

✦

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It will include the ability to store the buffer pool in shared memory and built-in response time distribution stats.

It will also feature HandlerSocket.

XtraBackup Plans ★

XtraBackup 1.5 will support parallel backup: ✦

★

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http://www.percona.com/docs/wiki/perconaxtrabackup:xtrabackup:option-and-variablereference#parallel

This is very helpful for RAID controllers and some SSDs, which require multiple threads to exploit their capacity.

Support & Maintenance ★ ★

Feature development is customer-driven.

Commercial Support and Maintenance for Percona Server, XtraDB and XtraBackup are available. ✦

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http://www.percona.com/support/mysql-supportmaintenance/

Support & Maintenance (cont.) â&#x2DC;&#x2026;

â&#x2DC;&#x2026;

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Seeking sponsorship of parallel replication: http://www.mysqlperformanceblog.com/2010/11/08/ implementing-parallel-replication-in-mysql/ We need to get more customers involved, to share the cost of this large and ambitious project.

Support & Maintenance (cont.) ★

Provides you with: ✦

✦

✦

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Expert technical advice.

Insurance against bugs in MySQL. Customized server binaries.

Today’s Agenda ★ ★ ★ ★ ★

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Percona products at 10 000 feet.

A closer look at Percona Server with XtraDB. A closer look at XtraBackup.

A quick look into the future.

Finding more information.

Getting Started ★

Percona Server with XtraDB and XtraBackup are free software released under the GPL license. ✦

★

We provide YUM and APT repositories: ✦

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More information can be found at: http://www.percona.com/software/percona-server/ http://www.percona.com/software/percona-xtrabackup/ http://www.percona.com/docs/wiki/release:start

Training Classes ★

Chicago Tuesday, 01 Feb 2011 to Friday, 04 Feb 2011

★

London Monday, 21 Feb 2011 to Thursday, 24 Feb 2011

★

Frankfurt Monday, 28 Feb 2011 to Thursday, 03 Mar 2011

★ ★

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See www.percona.com/training to register.

Private training and combined onsite consulting/training is available.

Any Questions?

Slides and a recording will be made available after this presentation.

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