介绍 Percona 服务器 XtraDB 和 Xtrabackup http://www.ossez.com/forum.php?mod=viewthread&tid=26841&fromuid=426 (出处: OSSEZ)

1. Introduction to Percona Server,
XtraDB and Xtrabackup
Morgan Tocker
morgan@percona.com
1

2. Who is Percona?
2
CONSULTING SUPPORT TRAINING MAINTENANCE
.. for MySQL.

3. Who is Percona?
2
CONSULTING SUPPORT TRAINING MAINTENANCE
.. for MySQL.

4. Who is Percona?
2
CONSULTING SUPPORT TRAINING MAINTENANCE
.. for MySQL.

5. Who is Percona?
2
CONSULTING SUPPORT TRAINING MAINTENANCE
.. for MySQL.

6. Who is Percona?
2
CONSULTING SUPPORT TRAINING MAINTENANCE
.. for MySQL.

7. Today’s Agenda
★ 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.
3

8. 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

9. Percona Server is...
★ A Percona sponsored distribution of the MySQL Server.
✦
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.
5

10. XtraDB is..
★ An enhanced version of the InnoDB storage engine.
✦
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”.
6

11. XtraBackup is...
★ 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.
7

12. A fork or a spoon?
★ Percona Server and XtraDB are forks by definition.
✦
We change the name to help users identify our distinctively
different set of features.
★ Don’t let the word fork scare you.
✦
~30K lines changed out of millions.
✦
We rebase off newer official MySQL releases.
✦
License remains as GPL (Open Source).
✦
Compatibility is maintained.
8

13. A word on compatibility:
★ The file format between MySQL with InnoDB to Percona
Server with XtraDB does not change.*
★ XtraDB identifies itself as InnoDB:
✦
ALTER TABLE my_table ENGINE=INNODB; or CREATE
TABLE my_table (a INT) ENGINE=INNODB; still works!
★ If you want to revert back, just remove the Percona
Packages and install MySQL packages.
✦
Both Debian/Red Hat packages don’t remove the data
directory when you remove the programs.
9 * By default. You must explicitly enable features for incompatibility.

14. Compatibility (cont.)
★ 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.
10

15. Today’s Agenda
★ 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.
11

16. 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
12
Major MySQL Version
(MySQL 5.1)
Minor MySQL Version
(MySQL 5.1.52)
XtraDB Release Version
(Release 11.6)

17. ★ Historical average of a new release every 2 months:
Releases History
13
Release-1 Dec 2008
Release-2 Dec 2008
Release-3 Feb 2009
Release-4 April 2009
Release-5 April 2009
Release-6 July 2009
Release-7 August 2009
Release-8 Oct 2009
Release-9 Jan 2010
Release-9.1 March 2010
Release-10 April 2010
Release-10.1 May 2010
Release-11.0* June 2010
Release-11.1 June 2010
Release-11.2 July 2010
Release-11.3 September 2010
Release-12.0 September 2010
Release-11.4 October 2010
Release-12.1 October 2010
Release-11.5 October 2010
Release-11.6 November 2010
* Recalled Release. The 12.1 branch is now ‘Release Candidate’.

18. So what changes?
★ Most of the enhancements fall into two categories:
✦
Performance Improvements
✦
Operational / Usability Features
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19. Performance Improvements
15
Improved Buffer
Pool Scalability
Faster Crash Recovery
Improved IO Path
+ adaptive checkpointing
Improved Rollback
Segment Scalability*Separate purge thread
Data dictionary
memory consumption
controls
Increased number of
undo slots*
Faster page
checksums*
Support for different
page sizes*
Insert buffer controls
Completely
disable the query
cache.
Remove excess fcntl calls
Per session configuration of
innodb_flush_log_at_trx_commit
Separate location
of double write
buffer*
Strip comments before
using query cache
Transaction logs
larger than 4G
supported.
* Changes on disk format. Must use mysqldump to revert to regular MySQL releases.

20. It’s not all raw performance
★ Many people get carried away
with performance.
✦
Consistency of timing is also more
important than raw throughput.
✦
Without diagnostics, you won’t get
what you are entitled to.
16
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/

21. Stability of results
★ A lot of engineering work has
been done to minimize
variance.
★ Sharp drops in MySQL
releases are caused by
checkpointing activities.
17
Benchmarks is available at
http://www.percona.com/software/benchmarks/

22. Usability Enhancements
18
Show contents of
the buffer pool
Import / export of
innodb_file_per_table
tables
Import / export of
buffer pool
contents
Transactional
Replication
Better handling of
corrupted tables
Store buffer pool
in shared memory
segment
Save index statistics
between restarts
Advise in
processlist when
waiting on Query
cache mutex.
Improved slow
query log
User / Index / Table statistics
Disable automatic
statistics
regeneration
Show data
dictionary
Deadlock counter
Show Temporary Tables
Log connection
errors
Retain query
response time
distribution.
Bug fixes - ahead
of time

23. $ mysql -e “SET GLOBAL log_slow_verbosity = ‘full’;”
$ 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;
$ tail /var/log/mysql.slow
..
# 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 Server
Percona Server
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The slow query log

24. Slow log (cont.)
★ In XtraDB 12.1, this is even further enhanced:
20
$ 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;

25. mysql> SET GLOBAL userstat_running = 1;
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)
MySQL Server
Percona Server
( Not Possible )
21
Find indexes not being used

26. 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?
✦
We have a new SHOW PROCESSLIST state.
22

27. Show Buffer Pool Contents
23
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)
Source: http://www.mysqlperformanceblog.com/
2010/03/26/tables-fit-buffer-poo/

28. Save Buffer Pool Contents
★ Export the contents of the buffer pool to a file called
‘ib_lru_dump’ in the data directory:
✦
SELECT * FROM
information_schema.XTRADB_ADMIN_COMMAND /*!
XTRA_LRU_DUMP*/;
★ Restored ib_lru_dump:
✦
SELECT * FROM
information_schema.XTRADB_ADMIN_COMMAND /*!
XTRA_LRU_RESTORE*/;
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Note: Not the actual contents - it takes 8 bytes to
remember the address of a 16K page.

29. To summarize
★ Many MySQL users are not getting the performance
they are entitled to.
✦
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.
25

30. Today’s Agenda
★ 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.
26

31. Backup Overview in MySQL
27
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
Popular for small
databases.
Popular for databases
with MyISAM
Best choice
when all InnoDB

32. What’s the difference between..?
★ 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.
28
See: http://www.mysqlperformanceblog.com/2009/02/05/
disaster-lvm-performance-in-snapshot-mode/
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

33. But you said...
★ Mysqldump may be faster in
a few cases.
★ Concern yourself more with
recovery time and impact.
29
http://www.mysqlperformanceblog.com/2010/11/08/an-
argument-for-not-using-mysqldump-in-production/
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

34. XtraBackup is...
★ The best option when you have a considerable amount
of data:
✦
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.
30

35. InnoDB Hot Backup (1)
31
Feature
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
More Information:
http://www.percona.com/software/percona-xtrabackup/

36. InnoDB Hot Backup (2)
32
Feature
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
More Information:
http://www.percona.com/software/percona-xtrabackup/

37. Advanced Features
★ XtraBackup supports some advanced backup options:
✦
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.*
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* Some special restrictions apply.
Data Definition must not have changed since last backup.

38. Advanced Features (cont.)
★ 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%
...
34
http://www.mysqlperformanceblog.com/2009/09/14/statistics-
of-innodb-tables-and-indexes-available-in-xtrabackup/

39. Today’s Agenda
★ 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.
35

40. MySQL 5.5
★ In Release Candidate now.
★ An awesome release!
✦
A greatly improved focus on performance.
✦
Some additional diagnostic/usability features.
★ Percona Server will rebase against 5.5.
✦
Work has already began porting features.
✦
We will continue to maintain our 5.1 series.
36

41. 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.
✦
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.
37

42. XtraBackup Plans
★ XtraBackup 1.5 will support parallel backup:
✦
http://www.percona.com/docs/wiki/percona-
xtrabackup:xtrabackup:option-and-variable-
reference#parallel
★ This is very helpful for RAID controllers and some SSDs,
which require multiple threads to exploit their capacity.
38

43. Support & Maintenance
★ Feature development is customer-driven.
★ Commercial Support and Maintenance for Percona
Server, XtraDB and XtraBackup are available.
✦
http://www.percona.com/support/mysql-support-
maintenance/
39

44. Support & Maintenance (cont.)
★ 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.
40

45. Support & Maintenance (cont.)
★ Provides you with:
✦
Expert technical advice.
✦
Insurance against bugs in MySQL.
✦
Customized server binaries.
41

46. Today’s Agenda
★ 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.
42

47. Getting Started
★ Percona Server with XtraDB and XtraBackup are free
software released under the GPL license.
✦
More information can be found at:
http://www.percona.com/software/percona-server/
http://www.percona.com/software/percona-xtrabackup/
★ We provide YUM and APT repositories:
✦
http://www.percona.com/docs/wiki/release:start
43

48. Training Classes
★ See www.percona.com/training to register.
★ Private training and combined onsite consulting/training
is available.
44
★ 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

49. Any Questions?
45
Slides and a recording will be made available
after this presentation.