Mais conteúdo relacionado Semelhante a MySQL SYS Schema Deep Dive Semelhante a MySQL SYS Schema Deep Dive (20) MySQL SYS Schema Deep Dive1. Copyright © 2016, Oracle and/or its affiliates. All rights reserved.
MySQL SYS Schema
Deep Dive
Mark Leith
Senior Software Development Manager
MySQL Enterprise Tools, Oracle
2. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
Program Agenda
Introduction to the MySQL sys schema
Installation
Formatting / Helper Routines
Summary Views
Tracing Routines
1
2
3
4
5
3. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
Program Agenda
Introduction to the MySQL sys schema
Installation
Formatting / Helper Routines
Summary Views
Tracing Routines
1
2
3
4
5
4. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
Why the sys schema?
• Performance Schema exposes a huge amount of data
• Many of its tables can implement multiple different use cases,
depending on the type of data
• The sys schema layers on top the (sometimes complex) queries in to a
packaged set of easy to use views
• It also adds a number of functions and procedures that help format,
configure the output of, and record, Performance Schema data
• Implements many of the common day to day DBA and Developer
debugging and tuning use cases
5. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
Program Agenda
Introduction to the MySQL sys schema
Installation
Formatting / Helper Routines
Summary Views
Tracing Routines
1
2
3
4
5
6. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
Installation from the command line
• $ git clone https://github.com/mysql/mysql-sys.git /tmp/sys
• $ cd /tmp/sys
• $ mysql -u user -p < sys_<version>.sql
<version> can be 56 or 57, for 5.6 and 5.7 respectively
7. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
Installation from MySQL Workbench 6.1+
8. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
Installation on the new MySQL 5.7 GA
• Do nothing other than install/mysql_upgrade it is there by default!
• You will be able to install future upgrades from the sys repository
as you wish, no restrictions there
9. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
select * from sys.version;
+-------------+---------------+
| sys_version | mysql_version |
+-------------+---------------+
| 1.5.1 | 5.7.14-log |
+-------------+---------------+
9
Checking sys is loaded
mysql> select *
-> from sys.schema_object_overview
-> where db = 'sys';
+-----+---------------+-------+
| db | object_type | count |
+-----+---------------+-------+
| sys | BASE TABLE | 1 |
| sys | INDEX (BTREE) | 1 |
| sys | TRIGGER | 2 |
| sys | FUNCTION | 22 |
| sys | PROCEDURE | 26 |
| sys | VIEW | 100 |
+-----+---------------+-------+
10. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
Program Agenda
Introduction to the MySQL sys schema
Installation
Formatting / Helper Routines
Summary Views
Tracing Routines
1
3
2
4
5
11. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
• Make output human readable
• Format time appropriately
• Format bytes appropriately
• Truncate output for large
width values for CLI
• Extract object names
• Check instrumentation state
11
Formatting / Helper Functions
format_time
format_bytes
format_path
format_statement
extract_table_from_file_name
extract_schema_from_file_name
ps_is_account_enabled
ps_is_consumer_enabled
ps_is_instrument_default_enabled
ps_is_instrument_default_timed
ps_is_thread_instrumented
12. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
format_time() function
mysql> select format_time(23849723429) as time
-> union select format_time(8327423749233)
-> union select format_time(83274237492335);
+-------------+
| time |
+-------------+
| 23.85 ms |
| 8.33 s |
| 00:01:23.27 |
+-------------+
13. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
format_bytes() function
mysql> select format_bytes(23423) as bytes
-> union select format_bytes(23432423)
-> union select format_bytes(42839479283)
-> union select format_bytes(2293848203489);
+-----------+
| bytes |
+-----------+
| 22.87 KiB |
| 22.35 MiB |
| 39.90 GiB |
| 2.09 TiB |
+-----------+
14. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
Performance Schema Config Helper Procedures
• ps_setup_show_disabled() / ps_setup_show_enabled()
• ps_setup_disable_thread() / ps_setup_enable_thread()
• ps_setup_disable_background_threads() /
ps_setup_enable_background_threads()
• ps_setup_disable_instrument() / ps_setup_enable_instrument()
• ps_setup_disable_consumer() / ps_setup_enable_consumer()
• ps_setup_save() / ps_setup_reload_saved()
• ps_setup_reset_to_default() / ps_truncate_all_tables()
15. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
Program Agenda
Introduction to the MySQL sys schema
Installation
Formatting / Helper Routines
Summary Views
Tracing Routines
1
4
2
3
5
16. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
MySQL sys views
• Reference set of views solving various administrator use cases
• Simple views, create/copy your own, sys is not “locked down”
• Build upon both performance_schema and INFORMATION_SCHEMA
• Both formatted and raw views are available
• All raw views are prefixed with x$
• Raw views are there for tools to poll
• Formatted views are for humans and the command line
17. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
• High level user/host overviews
• Breakdowns by:
• IO usage
• Stages
• Statement details
• Following show users only
17
User / Host Summary Views
user_summary
user_summary_by_file_io
user_summary_by_file_io_type
user_summary_by_stages
user_summary_by_statement_latency
user_summary_by_statement_type
host_summary
host_summary_by_file_io
host_summary_by_file_io_type
host_summary_by_stages
host_summary_by_statement_latency
host_summary_by_statement_type
18. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
user_summary view
mysql> select * from user_summaryG
*************************** 1. row ***************************
user: mark
statements: 3072
statement_latency: 1.77 s
statement_avg_latency: 575.29 us
table_scans: 7
file_ios: 20043
file_io_latency: 346.79 ms
current_connections: 1
total_connections: 1
unique_hosts: 1
current_memory: 515.81 KiB
total_memory_allocated: 30.69 MiB
MySQL 5.7
19. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
user_summary_by_file_io_type view
mysql> select * from user_summary_by_file_io_type;
+------+--------------------------------------+---------+-------------+-------------+
| user | event_name | total | latency | max_latency |
+------+--------------------------------------+---------+-------------+-------------+
| mark | wait/io/file/myisam/dfile | 19540 | 215.20 ms | 120.79 ms |
| mark | wait/io/file/myisam/kfile | 501 | 131.58 ms | 57.74 ms |
| mark | wait/io/file/sql/dbopt | 2 | 17.29 us | 9.17 us |
| root | wait/io/file/innodb/innodb_log_file | 2079432 | 00:28:27.62 | 1.30 s |
| root | wait/io/file/myisam/kfile | 5195927 | 00:17:07.33 | 1.17 s |
| root | wait/io/file/myisam/dfile | 1533813 | 00:07:27.59 | 1.18 s |
| root | wait/io/file/sql/binlog | 3517008 | 00:03:07.34 | 1.42 s |
| root | wait/io/file/innodb/innodb_data_file | 20720 | 00:02:37.81 | 492.23 ms |
| root | wait/io/file/sql/FRM | 41412 | 3.17 s | 80.43 ms |
| root | wait/io/file/sql/dbopt | 110993 | 1.23 s | 63.27 ms |
20. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
user_summary_by_statement_latency view
mysql> select * from user_summary_by_statement_latencyG
*************************** 1. row ***************************
user: mark
total: 176
total_latency: 1.26 s
max_latency: 583.33 ms
lock_latency: 216.95 ms
rows_sent: 311
rows_examined: 307
rows_affected: 0
full_scans: 7
21. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
user_summary_by_statement_type view
mysql> select * from user_summary_by_statement_typeG
*************************** 1. row ***************************
user: mark
statement: commit
total: 2463190
total_latency: 13.33h
max_latency: 12.18 s
lock_latency: 0 ps
rows_sent: 0
rows_examined: 0
rows_affected: 0
full_scans: 0
22. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
• IO by current threads
• Global summaries by file and
class, aggregating by bytes or
latency
• Stream of last file IO events in
raw form
22
IO Summary Views
io_by_thread_by_latency
io_global_by_file_by_bytes
io_global_by_file_by_latency
io_global_by_wait_by_bytes
io_global_by_wait_by_latency
23. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
io_by_thread_by_latency view
mysql> select * from io_by_thread_by_latencyG
*************************** 1. row ***************************
user: main
total: 1193
total_latency: 136.45 ms
min_latency: 731.38 ns
avg_latency: 269.99 us
max_latency: 20.72 ms
thread_id: 1
processlist_id: NULL
*************************** 2. row ***************************
user: root@localhost
total: 533
total_latency: 53.81 ms
min_latency: 780.39 ns
avg_latency: 8.41 ms
max_latency: 25.06 ms
thread_id: 23
processlist_id: 4
24. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
io_global_by_file_by_latency view
mysql> select * from io_global_by_file_by_latency limit 1G
*************************** 1. row ***************************
file: @@datadir/ibdata1
total: 1395714
total_latency: 00:28:53.06
count_read: 1006
read_latency: 4.51 s
count_write: 1326529
write_latency: 33.39 s
count_misc: 68179
misc_latency: 00:28:15.16
25. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
latest_file_io view
mysql> select * from latest_file_io;
+-----------------------------+----------------------------------+-----------+-----------+-----------+
| thread | file | latency | operation | requested |
+-----------------------------+----------------------------------+-----------+-----------+-----------+
| root@localhost:63153:179371 | @@datadir/ib_logfile1 | 7.16 us | lock | NULL |
| root@localhost:63153:179371 | @@datadir/ib_logfile1 | 6.16 us | write | 1.50 KiB |
| root@localhost:63153:179371 | @@datadir/ib_logfile1 | 14.36 ms | sync | NULL |
| root@localhost:63153:179371 | @@datadir/cerberus-bin.000012 | 28.25 us | write | 905 bytes |
| root@localhost:63177:179394 | @@datadir/ib_logfile1 | 15.25 us | write | 1.00 KiB |
| root@localhost:57487:3 | @@datadir/cerberus-bin.000012 | 32.12 us | read | 905 bytes |
| root@localhost:63177:179394 | @@datadir/ib_logfile1 | 6.65 us | write | 1.00 KiB |
| root@localhost:63177:179394 | @@datadir/ib_logfile1 | 213.32 us | sync | NULL |
| root@localhost:63177:179394 | @@datadir/ib_logfile1 | 17.27 us | write | 1.00 KiB |
| root@localhost:63177:179394 | @@datadir/ib_logfile1 | 286.01 us | sync | NULL |
| root@localhost:63177:179394 | @@datadir/cerberus-bin.000012 | 18.77 us | write | 601 bytes |
| root@localhost:57487:3 | @@datadir/cerberus-bin.000012 | 7.55 us | read | 601 bytes |
| root@localhost:63177:179394 | @@datadir/ib_logfile1 | 10.67 us | write | 1.00 KiB |
| root@localhost:63177:179394 | @@datadir/ib_logfile1 | 200.28 us | sync | NULL |
| root@localhost:63177:179394 | @@datadir/cerberus-bin.000012 | 12.91 us | write | 601 bytes |
| root@localhost:57487:3 | @@datadir/cerberus-bin.000012 | 6.47 us | read | 601 bytes |
| root@localhost:63177:179394 | @@datadir/ib_logfile1 | 9.22 us | write | 1.50 KiB |
……
26. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
• Object overview
• Table usage statistics
• Index usage statistics
• Following show users only
26
Schema Analysis Views
schema_index_statistics
schema_object_overview
schema_table_statistics
schema_table_statistics_with_buffer
schema_tables_with_full_table_scans
schema_unused_indexes
27. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
schema_table_statistics view
mysql> select * from schema_table_statistics limit 1G
*************************** 1. row ***************************
table_schema: mem__quan
table_name: normalized_statements_by_server_by_schema_data
total_latency: 00:55:07.80
rows_fetched: 239685
fetch_latency: 17.10 s
rows_inserted: 1102895
insert_latency: 00:52:18.10
rows_updated: 55910
update_latency: 00:02:28.62
rows_deleted: 17899
delete_latency: 3.98 s
io_read_requests: 20639
io_read: 324.94 MiB
io_read_latency: 00:03:04.10
io_write_requests: 1965973
io_write: 40.36 GiB
io_write_latency: 25.46 s
io_misc_requests: 18217
io_misc_latency: 00:14:06.02
28. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
schema_index_statistics view
mysql> select * from schema_index_statistics limit 1G
*************************** 1. row ***************************
table_schema: mem__inventory
table_name: mysqlconnectionconfiguration
index_name: PRIMARY
rows_selected: 131399
select_latency: 00:07:05.03
rows_inserted: 0
insert_latency: 0 ps
rows_updated: 41608
update_latency: 21.96 s
rows_deleted: 0
delete_latency: 0 ps
29. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
schema_tables_with_full_table_scans view
mysql> select * from schema_tables_with_full_table_scans limit 10;
+--------------------+--------------------------------+-------------------+-----------+
| object_schema | object_name | rows_full_scanned | latency |
+--------------------+--------------------------------+-------------------+-----------+
| mem30__instruments | fsstatistics | 10207042 | 13.10 s |
| mem30__instruments | preparedstatementapidata | 436428 | 973.27 ms |
| mem30__instruments | mysqlprocessactivity | 411702 | 282.07 ms |
| mem30__instruments | querycachequeriesincachedata | 374011 | 767.15 ms |
| mem30__instruments | rowaccessesdata | 322321 | 1.55 s |
| mem30__instruments | connectionsmaxdata | 301242 | 857.63 ms |
| mem30__instruments | innodbdatadictionarymemorydata | 292564 | 495.38 ms |
| mem30__instruments | innodbbufferpooldata | 277112 | 1.95 s |
| mem30__instruments | avgrowaccessesdata | 269236 | 1.25 s |
| mem30__instruments | innodbrowdetailsdata | 248208 | 653.25 ms |
+--------------------+--------------------------------+-------------------+-----------+
30. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
schema_unused_indexes view
mysql> select * from schema_unused_indexes limit 10;
+--------------------+-----------------------------------+--------------------+
| object_schema | object_name | index_name |
+--------------------+-----------------------------------+--------------------+
| mem30__bean_config | plists | path |
| mem30__config | group_selections | name |
| mem30__config | notification_groups | name |
| mem30__config | user_form_defaults | FKC1AEF1F9E7EE2CFB |
| mem30__enterprise | whats_new_entries | entryId |
| mem30__events | action_logs | policyId |
| mem30__events | action_logs | eventId |
| mem30__events | action_logs | ts |
| mem30__events | advisor_scopes_advisorcategoryids | FKF0CB0DB962CAB4 |
| mem30__events | advisor_scopes_advisorclassids | FK650AF1BF962CAB4 |
+--------------------+-----------------------------------+--------------------+
You should ensure you have representative time frame before taking any actions!
31. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
• Wait summaries by class
• Wait details per:
• User
• Host
• Globally
31
Wait Analysis Views
wait_classes_global_by_avg_latency
wait_classes_global_by_latency
waits_by_host_by_latency
waits_by_user_by_latency
waits_global_by_latency
32. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
waits_global_by_latency view
mysql> select * from waits_global_by_latency limit 10;
+--------------------------------------+----------+---------------+-------------+-------------+
| events | total | total_latency | avg_latency | max_latency |
+--------------------------------------+----------+---------------+-------------+-------------+
| wait/io/table/sql/handler | 24196659 | 1.75h | 259.72 us | 2.29 s |
| wait/io/file/innodb/innodb_data_file | 5964255 | 1.36h | 822.01 us | 1.49 s |
| wait/io/file/innodb/innodb_log_file | 2272647 | 00:36:41.37 | 968.64 us | 1.30 s |
| wait/io/file/myisam/kfile | 5463587 | 00:18:14.16 | 200.26 us | 1.17 s |
| wait/io/file/myisam/dfile | 1715187 | 00:08:00.18 | 279.96 us | 1.18 s |
| wait/io/file/sql/binlog | 3722079 | 00:03:23.71 | 54.73 us | 1.42 s |
| wait/lock/table/sql/handler | 10074274 | 00:01:56.63 | 11.58 us | 186.90 ms |
| wait/io/socket/sql/client_connection | 3879827 | 25.36 s | 6.54 us | 219.25 ms |
| wait/io/file/sql/FRM | 43994 | 3.27 s | 74.35 us | 80.43 ms |
| wait/io/file/sql/dbopt | 116765 | 1.29 s | 11.03 us | 63.27 ms |
+--------------------------------------+----------+---------------+-------------+-------------+
InnoDB only instance, this MyISAM IO is all temporary tables, focus tuning there!
33. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
waits_by_user_by_latency view
mysql> select * from waits_by_user_by_latency;
+------+--------------------------------------+----------+---------------+-------------+-------------+
| user | event | total | total_latency | avg_latency | max_latency |
+------+--------------------------------------+----------+---------------+-------------+-------------+
| mark | wait/io/file/myisam/dfile | 19540 | 215.20 ms | 11.01 us | 120.79 ms |
| mark | wait/io/file/myisam/kfile | 501 | 131.58 ms | 262.63 us | 57.74 ms |
| mark | wait/io/file/sql/dbopt | 2 | 17.29 us | 8.64 us | 9.17 us |
| root | wait/io/table/sql/handler | 24189319 | 1.74h | 258.77 us | 2.29 s |
| root | wait/io/file/innodb/innodb_log_file | 2162650 | 00:30:52.87 | 856.76 us | 1.30 s |
| root | wait/io/file/myisam/kfile | 5460992 | 00:18:12.83 | 200.11 us | 1.17 s |
| root | wait/io/file/myisam/dfile | 1694624 | 00:07:59.50 | 282.95 us | 1.18 s |
| root | wait/io/file/sql/binlog | 3711637 | 00:03:23.16 | 54.74 us | 1.42 s |
| root | wait/io/file/innodb/innodb_data_file | 22577 | 00:03:05.73 | 8.23 ms | 492.23 ms |
| root | wait/lock/table/sql/handler | 10069000 | 00:01:56.59 | 11.58 us | 186.90 ms |
……
root is doing the most temporary table IO
34. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
• Table Metadata Lock Waits
• InnoDB Row Lock Waits
34
Lock Wait Views
schema_table_lock_waits
innodb_lock_waits
35. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
sys.schema_table_lock_waits
mysql> select * from sys.schema_table_lock_waitsG
*************************** 1. row ***************************
object_schema: test
object_name: t
waiting_thread_id: 43
waiting_pid: 21
waiting_account: msandbox@localhost
waiting_lock_type: SHARED_UPGRADABLE
waiting_lock_duration: TRANSACTION
waiting_query: alter table test.t add foo int
waiting_query_secs: 988
waiting_query_rows_affected: 0
waiting_query_rows_examined: 0
blocking_thread_id: 42
blocking_pid: 20
blocking_account: msandbox@localhost
blocking_lock_type: SHARED_NO_READ_WRITE
blocking_lock_duration: TRANSACTION
sql_kill_blocking_query: KILL QUERY 20
sql_kill_blocking_connection: KILL 20
36. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
sys.innodb_lock_waits
mysql> SELECT * FROM sys.innodb_lock_waitsG
*************************** 1. row ***************************
wait_started: 2014-11-11 13:39:20
wait_age: 00:00:07
wait_age_secs: 7
locked_table: `db1`.`t1`
locked_index: PRIMARY
locked_type: RECORD
waiting_trx_id: 867158
waiting_trx_started: 2014-11-11 13:39:15
waiting_trx_age: 00:00:12
waiting_trx_rows_locked: 0
waiting_trx_rows_modified: 0
waiting_pid: 3
waiting_query: UPDATE t1 SET val = val + 1 WHERE id = 2
waiting_lock_id: 867158:2363:3:3
waiting_lock_mode: X
blocking_trx_id: 867157
blocking_pid: 4
...
blocking_query: UPDATE t1 SET val …
blocking_lock_id: 867157:2363:3:3
blocking_lock_mode: X
blocking_trx_started: 2014-11-11 13:39:11
blocking_trx_age: 00:00:16
blocking_trx_rows_locked: 1
blocking_trx_rows_modified: 1
sql_kill_blocking_query: KILL QUERY 4
sql_kill_blocking_connection: KILL 4
37. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
• Statement overview
• Find statements by:
• Those with errors
• Those with full table scans
• Those creating temp tables
• Those that cause sorting
• With latency in 95th %ile
37
Statement Analysis Views
statement_analysis
statements_with_errors_or_warnings
statements_with_full_table_scans
statements_with_runtimes_in_95th_p
ercentile
statements_with_sorting
statements_with_temp_tables
38. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
statement_analysis view
mysql> select * from statement_analysis limit 2G
*************************** 1. row ***************************
query: INSERT INTO `mem30__quan` . `n ... nDuration` = IF ( VALUES ( ...
db: mem
full_scan:
exec_count: 4657
err_count: 0
warn_count: 0
total_latency: 00:03:57.40
max_latency: 10.54 s
avg_latency: 50.98 ms
lock_latency: 00:03:00.93
rows_sent: 0
rows_sent_avg: 0
rows_examined: 0
rows_examined_avg: 0
rows_affected: 4794
rows_affected_avg: 1
tmp_tables: 0
tmp_disk_tables: 0
rows_sorted: 0
sort_merge_passes: 0
digest: b98bfe333642e8e4e72c73515810d865
first_seen: 2014-09-24 11:27:01
last_seen: 2014-09-24 11:53:00
39. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
statements_with_errors_or_warnings view
mysql> select * from statements_with_errors_or_warnings limit 1G
*************************** 1. row ***************************
query: CREATE TEMPORARY TABLE IF NOT ... _logs` ( `id` INT8 NOT NULL )
db: mem
exec_count: 1725
errors: 1725
error_pct: 100.0000
warnings: 0
warning_pct: 0.0000
first_seen: 2014-05-20 10:42:32
last_seen: 2014-05-21 18:39:22
digest: 51fb979dbc3910a6294c7cdabd7839c3
40. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
statements_with_temp_tables view
mysql> select * from statements_with_temp_tables limit 1G
*************************** 1. row ***************************
query: SELECT * FROM ( SELECT `digest ... ` ,
`sum_no_index_used` AS ...
db: mysql
exec_count: 68
total_latency: 2.31 s
memory_tmp_tables: 476
disk_tmp_tables: 204
avg_tmp_tables_per_query: 7
tmp_tables_to_disk_pct: 43
first_seen: 2014-09-24 11:26:18
last_seen: 2014-09-24 12:33:00
digest: 50761c6a1818824328745d8a136b9ed6
41. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
statements_with_full_table_scans view
mysql> select * from statements_with_full_table_scans limit 1G
*************************** 1. row ***************************
query: SELECT `pojotimese0_` . `id` A ...
ty_timeseries` `pojotimese0_`
db: mem
exec_count: 1
total_latency: 940.89 us
no_index_used_count: 1
no_good_index_used_count: 0
no_index_used_pct: 100
rows_sent: 116
rows_examined: 116
rows_sent_avg: 116
rows_examined_avg: 116
first_seen: 2014-09-24 11:25:03
last_seen: 2014-09-24 11:25:03
digest: f81b5ce10baee9be754cf35fd245a516
42. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
• Expose summary memory
usage by host, thread and user
• Show global usage
• Based on Performance Schema
memory instruments (disabled by
default, these need enabling)
42
Memory Views
memory_by_host_by_current_bytes
memory_by_thread_by_current_bytes
memory_by_user_by_current_bytes
memory_global_by_current_bytes
memory_global_total
43. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
memory_global_by_current_bytes view
mysql> select * from sys.memory_global_by_current_bytes limit 5G
*************************** 1. row ***************************
event_name: memory/innodb/buf_buf_pool
current_count: 6
current_alloc: 785.62 MiB
current_avg_alloc: 130.94 MiB
high_count: 6
high_alloc: 785.62 MiB
high_avg_alloc: 130.94 MiB
*************************** 2. row ***************************
event_name: memory/innodb/os0file
current_count: 431
current_alloc: 52.51 MiB
current_avg_alloc: 124.76 KiB
high_count: 434
…
InnoDB Buffer Pool
InnoDB file IO memory usage (various)
44. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
memory_by_thread_by_current_bytes view
mysql> select * from sys.memory_by_thread_by_current_bytes
-> where user not like 'innodb%' and user not like 'sql%';
+-----------+----------------+--------------------+-------------------+-------------------+-------------------+-----------------+
| thread_id | user | current_count_used | current_allocated | current_avg_alloc | current_max_alloc | total_allocated |
+-----------+----------------+--------------------+-------------------+-------------------+-------------------+-----------------+
| 176167 | root@localhost | 67 | 633.36 KiB | 9.45 KiB | 256.00 KiB | 246.06 MiB |
| 176220 | root@localhost | 67 | 246.73 KiB | 3.68 KiB | 73.46 KiB | 10.34 MiB |
| 176223 | root@localhost | 48 | 192.12 KiB | 4.00 KiB | 64.10 KiB | 1.03 MiB |
| 176221 | root@localhost | 49 | 180.79 KiB | 3.69 KiB | 64.10 KiB | 766.13 KiB |
| 176224 | root@localhost | 58 | 169.58 KiB | 2.92 KiB | 64.10 KiB | 4.26 MiB |
| 176225 | root@localhost | 83 | 159.06 KiB | 1.92 KiB | 64.10 KiB | 4.38 MiB |
| 176217 | root@localhost | 56 | 149.91 KiB | 2.68 KiB | 64.10 KiB | 5.75 MiB |
| 176226 | root@localhost | 68 | 148.90 KiB | 2.19 KiB | 64.10 KiB | 2.80 MiB |
| 176205 | root@localhost | 41 | 148.06 KiB | 3.61 KiB | 64.10 KiB | 5.08 MiB |
| 176204 | root@localhost | 51 | 143.25 KiB | 2.81 KiB | 64.10 KiB | 11.22 MiB |
| 176222 | root@localhost | 73 | 139.38 KiB | 1.91 KiB | 64.10 KiB | 1.46 MiB |
| 176201 | root@localhost | -33 | 122.04 KiB | -3787 bytes | 64.10 KiB | 14.55 MiB |
Note values can go negative if threads allocate
memory, but pass it to another thread to be freed,
this thread has freed memory from another thread
45. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
• Better SHOW PROCESSLIST
• No mutex contention
• Live statistics for query
• Consolidated metrics
45
Miscellaneous Views
processlist
session
metrics
46. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
processlist / session views
mysql> select * from sessionG
*************************** 1. row ***************************
thd_id: 7890
conn_id: 7870
user: root@localhost
db: mem
command: Query
state: update
time: 0
current_statement: /* mem dbpool.default */ inser ...<truncated>
lock_latency: 0 ps
rows_examined: 0
rows_sent: 0
rows_affected: 0
tmp_tables: 0
tmp_disk_tables: 0
full_scan: NO
last_statement: NULL
last_statement_latency: NULL
last_wait: wait/io/table/sql/handler
last_wait_latency: Still Waiting
source: handler.cc:7274
47. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
sys.sessions progress estimationmysql> select * from sys.sessionsG
*************************** 1. row ***************************
thd_id: 44524
conn_id: 44502
user: msandbox@localhost
db: test
command: Query
state: alter table (flush)
time: 18
current_statement: alter table t1 add column g int
statement_latency: 18.45 s
progress: 98.84
lock_latency: 265.43 ms
rows_examined: 0
rows_sent: 0
rows_affected: 0
tmp_tables: 0
tmp_disk_tables: 0
...
48. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
sys.metrics
mysql> select * from sys.metrics limit 199, 10;
+-----------------------------+----------------+--------------------------------------+---------+
| Variable_name | Variable_value | Type | Enabled |
+-----------------------------+----------------+--------------------------------------+---------+
| tc_log_page_waits | 0 | Global Status | YES |
| threads_cached | 7 | Global Status | YES |
| threads_connected | 3 | Global Status | YES |
| threads_created | 10 | Global Status | YES |
| threads_running | 3 | Global Status | YES |
| uptime | 275689 | Global Status | YES |
| uptime_since_flush_status | 275689 | Global Status | YES |
| adaptive_hash_pages_added | 0 | InnoDB Metrics - adaptive_hash_index | NO |
| adaptive_hash_pages_removed | 0 | InnoDB Metrics - adaptive_hash_index | NO |
| adaptive_hash_rows_added | 0 | InnoDB Metrics - adaptive_hash_index | NO |
+-----------------------------+----------------+--------------------------------------+---------+
performance_schema.global_status
information_schema.innodb_metrics
49. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
Program Agenda
Introduction to the MySQL sys schema
Installation
Formatting / Helper Routines
Summary Views
Tracing Routines
1
5
2
3
4
50. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
• Dump all P_S data to a dot
graph file to trace a thread
• Look in the statement history
table to capture more info on
a statement digest
• Show detailed transaction info
• Dump as much diagnostics info
as possible (support enabler)
50
Statement Tracing Routines
ps_trace_thread
ps_trace_statement_digest
ps_thread_trx_info
ps_thread_stack
ps_statement_avg_latency_histogram
diagnostics
51. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
ps_trace_statement_digest procedure
• ps_trace_statement_digest() analyses live traffic looking for
certain statement digest for a period of time
• Captures statistics on each matching statement it finds
• Returns a report of the captured stats
• An overall summary
• A break down for the longest running example
• An EXPLAIN (if the statement is not truncated)
52. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
ps_trace_statement_digest procedure
• ps_trace_statement_digest() parameters
• in_digest The statement digest to analyse
• in_runtime How long to run analysis for
• in_interval How often to snapshot data
• in_start_fresh Whether to truncate P_S tables first
• in_auto_enable Whether to auto enable required config
53. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
ps_trace_statement_digest procedure example
mysql> call ps_trace_statement_digest(‘6134e9d6f25eb8e6cddf11f6938f202a’, 60, 1, true, true);
+--------------------+
| SUMMARY STATISTICS |
+--------------------+
| SUMMARY STATISTICS |
+--------------------+
1 row in set (59.93 sec)
+------------+-----------+-----------+-----------+---------------+------------+------------+
| executions | exec_time | lock_time | rows_sent | rows_examined | tmp_tables | full_scans |
+------------+-----------+-----------+-----------+---------------+------------+------------+
| 360 | 1.41 s | 138.39 ms | 720 | 0 | 0 | 0 |
+------------+-----------+-----------+-----------+---------------+------------+------------+
1 row in set (59.93 sec)
+--------------------------------+-------+-----------+
| event_name | count | latency |
+--------------------------------+-------+-----------+
| stage/sql/Sending data | 14 | 1.10 s |
| stage/sql/update | 198 | 667.34 ms |
| stage/sql/removing tmp table | 9 | 240.48 ms |
...
54. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
ps_trace_statement_digest procedure example
+---------------------------+
| LONGEST RUNNING STATEMENT |
+---------------------------+
| LONGEST RUNNING STATEMENT |
+---------------------------+
1 row in set (59.95 sec)
+-----------+-----------+-----------+-----------+---------------+------------+-----------+
| thread_id | exec_time | lock_time | rows_sent | rows_examined | tmp_tables | full_scan |
+-----------+-----------+-----------+-----------+---------------+------------+-----------+
| 23277 | 77.64 ms | 97.00 us | 2 | 0 | 0 | 0 |
+-----------+-----------+-----------+-----------+---------------+------------+-----------+
1 row in set (59.95 sec)
+-------------------------------------------------------------------------------------------+
| sql_text |
+-------------------------------------------------------------------------------------------+
| /* mem dbpool.default */ insert into `mem__quan`.`normalized_statements_by_server_by_schema`
(firstSeen, lastSeen, normalized_statement_id, `schema`, server, id) values (1378983745000,
1378998600000, x'808ACEB88FC4B45BC47C4FE9D86C7F26', 'mem', '753c939e-1b99-11e3-b6d4-bc761a1f4f2f',
x'7CFE81F98B1E3FE0895D1AA2C39B326D') ON DUPLICATE KEY UPDATE ...
+-------------------------------------------------------------------------------------------+
...
55. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
ps_trace_statement_digest procedure example
+--------------------------------+----------+
| event_name | latency |
+--------------------------------+----------+
| stage/sql/init | 10.41 ms |
| stage/sql/checking permissions | 2.35 us |
| stage/sql/Opening tables | 10.32 us |
| stage/sql/init | 13.53 us |
| stage/sql/System lock | 3.66 us |
| stage/sql/update | 61.74 ms |
| stage/sql/end | 1.11 us |
| stage/sql/query end | 1.31 us |
| stage/sql/closing tables | 5.44 ms |
| stage/sql/freeing items | 23.31 us |
+--------------------------------+----------+
10 rows in set (59.99 sec)
+----+-------------+-------+------+---------------+------+---------+------+------+----------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+-------+------+---------------+------+---------+------+------+----------------+
| 1 | SIMPLE | NULL | NULL | NULL | NULL | NULL | NULL | NULL | No tables used |
+----+-------------+-------+------+---------------+------+---------+------+------+----------------+
...
56. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
sys.ps_thread_trx_info(<thread_id>)
SELECT sys.ps_thread_trx_info(48) as trx_infoG
*************************** 1. row ***************************
trx_info: [
{
"time": "790.70 us",
"state": "COMMITTED",
"mode": "READ WRITE",
"autocommitted": "NO",
"gtid": "AUTOMATIC",
"isolation": "REPEATABLE READ",
"statements_executed": [
{
"sql_text": "INSERT INTO info VALUES (1, 'foo')",
"time": "471.02 us",
"schema": "trx",
"rows_examined": 0,
"rows_affected": 1,
"rows_sent": 0,
"tmp_tables": 0,
"tmp_disk_tables": 0,
"sort_rows": 0,
"sort_merge_passes": 0
},
...
Pass in thread id
57. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
ps_trace_thread procedure
• ps_trace_thread() monitors a specific thread for a period
• Captures as much information on the thread activity as possible
• Returns a “dot” formatted file, that can graph the event hierarchy
• http://en.wikipedia.org/wiki/DOT_(graph_description_language)
58. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
ps_trace_thread procedure
• ps_trace_thread parameters
• in_thread_id The thread to analyse
• in_outfile The file to dump the data to (INTO OUTFILE)
• in_max_runtime How long to run analysis for
• in_interval How often to snapshot for data
• in_start_fresh Whether to truncate P_S tables first
• in_auto_setup Whether to auto enable required config
• in_debug Whether to also print debug info (source info)
59. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
ps_trace_thread procedure example
mysql> call ps_trace_thread(27768, '/tmp/stack_27768.dot', 60, 0.1, true, true, true);
+------------------------------------------------+
| Info |
+------------------------------------------------+
| Data collection starting for THREAD_ID = 27768 |
+------------------------------------------------+
1 row in set (4.82 sec)
+---------------------------------------------+
| Info |
+---------------------------------------------+
| Stack trace written to /tmp/stack_27768.dot |
+---------------------------------------------+
1 row in set (60.90 sec)
+--------------------------------------------------------+
| Convert to PDF |
+--------------------------------------------------------+
| dot -Tpdf -o /tmp/stack_27768.pdf /tmp/stack_27768.dot |
+--------------------------------------------------------+
1 row in set (60.90 sec)
+--------------------------------------------------------+
| Convert to PNG |
+--------------------------------------------------------+
| dot -Tpng -o /tmp/stack_27768.png /tmp/stack_27768.dot |
+--------------------------------------------------------+
1 row in set (60.90 sec)+
60. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
ps_trace_thread procedure example
cerberus:~ mark$ more Documents/statement_graphs/deletes.dot
digraph events {
graph [rankdir=LR, nodesep="0.10"];
node [label="N"];
graph [bb="0,0,1860,17476"];
1 [label="(0.20μ) mysys/THR_LOCK_threadsn", style=filled, color=lightskyblue, pos="209,18", width="3.19", height="0.50"];
2 [label="(0.18μ) sql/THD::LOCK_thd_datan", style=filled, color=lightskyblue, pos="209,61", width="3.06", height="0.50"];
3 [label="(0.24μ) sql/hash_filo::lockn", style=filled, color=lightskyblue, pos="209,104", width="2.42", height=“0.50"];
4 [label="(0.31μ) sql/LOGGER::LOCK_logger - read_lockn", style=filled, color=orchid, pos="209,147", width="4.22",
height="0.50"];
5 [label="(0.08μ) sql/LOG::LOCK_logn", style=filled, color=lightskyblue, pos="209,190", width="2.64", height="0.50"];
6 [label="(12.97μ) wait/io/file/sql/query_log - write 49 bytesn/Users/mark/mysql/lp-mysql-trunk/mysql-test/var/mysqld.1/
mysqld.logn", style=filled, color=red, shape=box, pos="209,235", width="5.78", height="0.56"];
7 [label="(176.14μ) sql/selectnselect @@version_comment limit 1nerrors: 0nwarnings: 0nlock time: 0.00μnrows affected:
0nrows sent:
209,18", width="3.19", height="0.50"];mp disk tables: 0nselect scan: 0nselect full join: :
2 [label="(0.18μ) sql/THD::LOCK_thd_datan", style=filled, color=lightskyblue, pos="209,61", width="3.06", height="0.50"];
3 [label="(0.24μ) sql/hash_filo::lockn", style=filled, color=lightskyblue, pos="209,104", width="2.42", height="0.50"];
4 [label="(0.31μ) sql/LOGGER::LOCK_logger - read_lockn", style=filled, color=orchid, pos="209,147", width="4.22",
height="0.50"];
5 [label="(0.08μ) sql/LOG::LOCK_logn", style=filled, color=lightskyblue, pos="209,190", width="2.64", height="0.50"];
……
61. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
ps_trace_thread procedure example
MySQL 5.7
Procedures
Transactions
Statements
Stages
Waits
68. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
Question time!
69. Copyright © 2014, Oracle and/or its affiliates. All rights reserved. |
Safe Harbor Statement
The preceding is intended to outline our general product direction. It is
intended for information purposes only, and may not be incorporated into any
contract. It is not a commitment to deliver any material, code, or functionality,
and should not be relied upon in making purchasing decisions. The development,
release, and timing of any features or functionality described for Oracle’s
products remains at the sole discretion of Oracle.