超出 Amazon RDS MySQL 5.5 Innodb Lock 等待超时

Question

超出 Amazon RDS MySQL 5.5 Innodb Lock 等待超时

Tra*_*vis 9 mysql innodb performance amazon-rds performance-tuning

自从我们迁移到 Amazon RDS 以来，我们遇到了一些非常疯狂的性能问题，今天我们开始遇到锁定问题。正因为如此，我认为这只是一个超时问题，并去检查我们使用的内存。我们交换了大约 70MB 的数据。我用 mysqltuner 进行了一次内存追捕，它说可能有大约 400% 的最大内存使用率。多亏了 Percona 的配置向导，我现在把它降到了 100% 以上。

但是，我们仍然有这个锁问题，所以我假设它与内存/交换无关。为什么我仍然收到锁定？这里发生了什么？

我相信重新启动将解决问题，但这不应该是解决方案。我们可以做些什么来防止将来发生这种情况？我尝试刷新查询缓存和表 - 有效。

由于 RDS，其他类型的冲洗不起作用：/

以下是我可以提供的大量信息：

询问

INSERT INTO `myTable` (`firstName`, `lastName`, `email`) VALUES ('Travis', 'B...', '...@gmail.com')

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错误信息

Lock wait timeout exceeded; try restarting transaction

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表模式

CREATE TABLE IF NOT EXISTS `myTable` (
  `id` int(15) NOT NULL AUTO_INCREMENT,
  `firstName` varchar(255) COLLATE utf8_unicode_ci NOT NULL,
  `lastName` varchar(255) COLLATE utf8_unicode_ci NOT NULL,
  `email` varchar(255) COLLATE utf8_unicode_ci NOT NULL,

  PRIMARY KEY (`id`),
  UNIQUE KEY `Unique Emails` (`email`),
  KEY `FullName` (`firstName`,`lastName`),
) ENGINE=InnoDB  DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=504 ;

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mysqltuner.pl

 >>  MySQLTuner 1.2.0 - Major Hayden <major@mhtx.net>
 >>  Bug reports, feature requests, and downloads at http://mysqltuner.com/
 >>  Run with '--help' for additional options and output filtering
[--] Performing tests on emp:3306
[OK] Logged in using credentials passed on the command line
[--] Assuming 17511 MB of physical memory
[!!] Assuming 0 MB of swap space (use --forceswap to specify)

-------- General Statistics --------------------------------------------------
[--] Skipped version check for MySQLTuner script
[OK] Currently running supported MySQL version 5.5.20-log

-------- Storage Engine Statistics -------------------------------------------
[--] Status: +Archive -BDB -Federated +InnoDB -ISAM -NDBCluster 
[--] Data in InnoDB tables: 451M (Tables: 75)
[--] Data in PERFORMANCE_SCHEMA tables: 0B (Tables: 17)
[!!] Total fragmented tables: 8

-------- Security Recommendations  -------------------------------------------
[OK] All database users have passwords assigned

-------- Performance Metrics -------------------------------------------------
[--] Up for: 32d 22h 37m 31s (6M q [2.145 qps], 29K conn, TX: 62B, RX: 2B)
[--] Reads / Writes: 60% / 40%
[--] Total buffers: 13.5G global + 28.6M per thread (150 max threads)
Use of uninitialized value $arch in string eq at ./mysqltuner.pl line 720 (#1)
    (W uninitialized) An undefined value was used as if it were already
    defined.  It was interpreted as a "" or a 0, but maybe it was a mistake.
    To suppress this warning assign a defined value to your variables.

    To help you figure out what was undefined, perl will try to tell you the
    name of the variable (if any) that was undefined. In some cases it cannot
    do this, so it also tells you what operation you used the undefined value
    in.  Note, however, that perl optimizes your program and the operation
    displayed in the warning may not necessarily appear literally in your
    program.  For example, "that $foo" is usually optimized into "that "
    . $foo, and the warning will refer to the concatenation (.) operator,
    even though there is no . in your program.

[!!] Maximum possible memory usage: 17.7G (103% of installed RAM)
[OK] Slow queries: 0% (7K/6M)
[OK] Highest usage of available connections: 61% (92/150)
[OK] Key buffer size / total MyISAM indexes: 32.0M/2.4M
[OK] Query cache efficiency: 82.1% (2M cached / 3M selects)
[OK] Query cache prunes per day: 0
[OK] Sorts requiring temporary tables: 0% (152 temp sorts / 106K sorts)
[OK] Temporary tables created on disk: 18% (17K on disk / 95K total)
[OK] Thread cache hit rate: 99% (92 created / 29K connections)
[!!] Table cache hit rate: 0% (86 open / 11K opened)
[OK] Open file limit used: 0% (9/65K)
[OK] Table locks acquired immediately: 99% (1M immediate / 1M locks)
[OK] InnoDB data size / buffer pool: 451.5M/12.7G

-------- Recommendations -----------------------------------------------------
General recommendations:
    Run OPTIMIZE TABLE to defragment tables for better performance
    Reduce your overall MySQL memory footprint for system stability
    Increase table_cache gradually to avoid file descriptor limits
Variables to adjust:
  *** MySQL's maximum memory usage is dangerously high ***
  *** Add RAM before increasing MySQL buffer variables ***
    table_cache (> 2048)

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显示 INNODB 引擎状态

=====================================
120820 18:33:44 INNODB MONITOR OUTPUT
=====================================
Per second averages calculated from the last 6 seconds
-----------------
BACKGROUND THREAD
-----------------
srv_master_thread loops: 330692 1_second, 330448 sleeps, 29989 10_second, 31250 background, 31249 flush
srv_master_thread log flush and writes: 332918
----------
SEMAPHORES
----------
OS WAIT ARRAY INFO: reservation count 67641, signal count 988874
Mutex spin waits 2257282, rounds 1886106, OS waits 12973
RW-shared spins 178174, rounds 1056448, OS waits 18278
RW-excl spins 606712, rounds 2742530, OS waits 32994
Spin rounds per wait: 0.84 mutex, 5.93 RW-shared, 4.52 RW-excl
------------
TRANSACTIONS
------------
Trx id counter 954707
Purge done for trx's n:o < 9535F2 undo n:o < 0
History list length 1943
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 0, not started
MySQL thread id 29763, OS thread handle 0x49a33940, query id 6086387LOCAL
sHOW ENGINE INNODB STATUS
---TRANSACTION 95454A, not started
MySQL thread id 29753, OS thread handle 0x49cfe940, query id 6085376EC2_1
---TRANSACTION 9543EB, not started
MySQL thread id 29752, OS thread handle 0x4a08c940, query id 6084567EC2_1
---TRANSACTION 95452A, not started
MySQL thread id 29746, OS thread handle 0x49768940, query id 6085452EC2_1
---TRANSACTION 9544BD, not started
MySQL thread id 29740, OS thread handle 0x4949d940, query id 6086384EC2_1
---TRANSACTION 954600, not started
MySQL thread id 29735, OS thread handle 0x4a51e940, query id 6086225EC2_1
---TRANSACTION 9546D1, not started
MySQL thread id 29712, OS thread handle 0x49b78940, query id 6086274 EC2_2
---TRANSACTION 9546AB, not started
MySQL thread id 29711, OS thread handle 0x497a9940, query id 6086169 EC2_2
---TRANSACTION 954587, not started
MySQL thread id 29707, OS thread handle 0x49c3b940, query id 6085510 EC2_2
---TRANSACTION 95453A, not started
MySQL thread id 29706, OS thread handle 0x49bb9940, query id 6085342 EC2_2
---TRANSACTION 9544CD, not started
MySQL thread id 29699, OS thread handle 0x499b1940, query id 6085099 EC2_2
---TRANSACTION 95464B, not started
MySQL thread id 29705, OS thread handle 0x4982b940, query id 6085987 EC2_2
---TRANSACTION 9545D4, not started
MySQL thread id 29704, OS thread handle 0x4172f940, query id 6085675 EC2_2
---TRANSACTION 9545F8, not started
MySQL thread id 29703, OS thread handle 0x4a357940, query id 6085800 EC2_2
---TRANSACTION 954468, not started
MySQL thread id 29702, OS thread handle 0x41a7f940, query id 6084853 EC2_2
---TRANSACTION 954496, not started
MySQL thread id 29700, OS thread handle 0x496e6940, query id 6084976 EC2_2
---TRANSACTION 95451A, not started
MySQL thread id 29701, OS thread handle 0x41a3e940, query id 6085264 EC2_2
---TRANSACTION 952531, not started
MySQL thread id 29690, OS thread handle 0x4165d940, query id 6066385 EC2_3
---TRANSACTION 954608, not started
MySQL thread id 29654, OS thread handle 0x416ee940, query id 6085838EC2_1
---TRANSACTION 952052, not started
MySQL thread id 29620, OS thread handle 0x49b37940, query id 6062029 EC2_3
---TRANSACTION 951EE8, not started
MySQL thread id 29608, OS thread handle 0x49f88940, query id 6060576 EC2_3
---TRANSACTION 951E7A, not started
MySQL thread id 29606, OS thread handle 0x41ac0940, query id 6060179 EC2_3
---TRANSACTION 0, not started
MySQL thread id 29417, OS thread handle 0x498ee940, query id 6081627LOCAL
---TRANSACTION 951EDE, not started
MySQL thread id 29463, OS thread handle 0x49f06940, query id 6060539 EC2_3
---TRANSACTION 954458, not started
MySQL thread id 29169, OS thread handle 0x49bfa940, query id 6084817EC2_1
---TRANSACTION 954403, not started
MySQL thread id 29154, OS thread handle 0x49af6940, query id 6085912EC2_1
---TRANSACTION 954625, not started
MySQL thread id 29173, OS thread handle 0x4a398940, query id 6085896EC2_1
---TRANSACTION 9546C1, not started
MySQL thread id 29170, OS thread handle 0x4a316940, query id 6086239EC2_1
---TRANSACTION 9544A2, not started
MySQL thread id 29168, OS thread handle 0x499f2940, query id 6085002EC2_1
---TRANSACTION 9545AD, not started
MySQL thread id 29153, OS thread handle 0x4945c940, query id 6085594EC2_1
---TRANSACTION 952679, not started
MySQL thread id 29418, OS thread handle 0x49cbd940, query id 6081627LOCAL
---TRANSACTION 9543F3, not started
MySQL thread id 29156, OS thread handle 0x49e02940, query id 6086208EC2_1
---TRANSACTION 954542, not started
MySQL thread id 29161, OS thread handle 0x41770940, query id 6085530EC2_1
---TRANSACTION 9546FE, not started
MySQL thread id 29150, OS thread handle 0x494de940, query id 6086368EC2_1
---TRANSACTION 954480, not started
MySQL thread id 29157, OS thread handle 0x41874940, query id 6085286EC2_1
---TRANSACTION 9546EF, not started
MySQL thread id 29155, OS thread handle 0x49e84940, query id 6086336EC2_1
---TRANSACTION 9544A5, not started
MySQL thread id 29174, OS thread handle 0x418b5940, query id 6085288EC2_1
---TRANSACTION 954522, not started
MySQL thread id 29158, OS thread handle 0x4a00a940, query id 6085281EC2_1
---TRANSACTION 954439, not started
MySQL thread id 29152, OS thread handle 0x4a2d5940, query id 6084755EC2_1
---TRANSACTION 9546D9, not started
MySQL thread id 29159, OS thread handle 0x4992f940, query id 6086289EC2_1
---TRANSACTION 9546E1, not started
MySQL thread id 29162, OS thread handle 0x49d3f940, query id 6086310EC2_1
---TRANSACTION 954706, not started
MySQL thread id 29151, OS thread handle 0x49560940, query id 6086381EC2_1
---TRANSACTION 954558, not started
MySQL thread id 29164, OS thread handle 0x417f2940, query id 6085402EC2_1
---TRANSACTION 95468A, not started
MySQL thread id 29172, OS thread handle 0x49dc1940, query id 6086104EC2_1
---TRANSACTION 95462D, not started
MySQL thread id 29171, OS thread handle 0x4a45b940, query id 6086031EC2_1
---TRANSACTION 9546F7, not started
MySQL thread id 29149, OS thread handle 0x4a14f940, query id 6086362EC2_1
---TRANSACTION 954597, not started
MySQL thread id 29163, OS thread handle 0x41978940, query id 6085714EC2_1
---TRANSACTION 954567, not started
MySQL thread id 29166, OS thread handle 0x49f47940, query id 6085434EC2_1
---TRANSACTION 954577, not started
MySQL thread id 29165, OS thread handle 0x49970940, query id 6086386EC2_1
---TRANSACTION 9545EE, not started
MySQL thread id 29211, OS thread handle 0x41b83940, query id 6085767EC2_4
---TRANSACTION 954532, not started
MySQL thread id 29193, OS thread handle 0x4951f940, query id 6085322EC2_4
---TRANSACTION 95457F, not started
MySQL thread id 29194, OS thread handle 0x41833940, query id 6085490EC2_4
---TRANSACTION 95466F, not started
MySQL thread id 29202, OS thread handle 0x4a3d9940, query id 6086048EC2_4
---TRANSACTION 9544C5, not started
MySQL thread id 29201, OS thread handle 0x497ea940, query id 6085081EC2_4
---TRANSACTION 954512, not started
MySQL thread id 29200, OS thread handle 0x4941b940, query id 6085245EC2_4
---TRANSACTION 9546C9, not started
MySQL thread id 29199, OS thread handle 0x4161c940, query id 6086256EC2_4
---TRANSACTION 95463D, not started
MySQL thread id 29198, OS thread handle 0x496a5940, query id 6085950EC2_4
---TRANSACTION 9545C4, not started
MySQL thread id 29197, OS thread handle 0x4a49c940, query id 6085645EC2_4
---TRANSACTION 954460, not started
MySQL thread id 29196, OS thread handle 0x4986c940, query id 6084834EC2_4
---TRANSACTION 94DEA8, not started
MySQL thread id 21921, OS thread handle 0x415db940, query id 6086180 localhost 127.0.0.1 rdsadmin
---TRANSACTION 94E45F, ACTIVE 12759 sec
20 lock struct(s), heap size 3112, 4 row lock(s), undo log entries 78
MySQL thread id 29195, OS thread handle 0x418f6940, query id 6084915EC2_4
--------
FILE I/O
--------
I/O thread 0 state: waiting for i/o request (insert buffer thread)
I/O thread 1 state: waiting for i/o request (log thread)
I/O thread 2 state: waiting for i/o request (read thread)
I/O thread 3 state: waiting for i/o request (read thread)
I/O thread 4 state: waiting for i/o request (read thread)
I/O thread 5 state: waiting for i/o request (read thread)
I/O thread 6 state: waiting for i/o request (write thread)
I/O thread 7 state: waiting for i/o request (write thread)
I/O thread 8 state: waiting for i/o request (write thread)
I/O thread 9 state: waiting for i/o request (write thread)
Pending normal aio reads: 0 [0, 0, 0, 0] , aio writes: 0 [0, 0, 0, 0] ,
 ibuf aio reads: 0, log i/o's: 0, sync i/o's: 0
Pending flushes (fsync) log: 0; buffer pool: 0
61692 OS file reads, 618676 OS file writes, 263209 OS fsyncs
0.00 reads/s, 0 avg bytes/read, 0.17 writes/s, 0.17 fsyncs/s
-------------------------------------
INSERT BUFFER AND ADAPTIVE HASH INDEX
-------------------------------------
Ibuf: size 1, free list len 27, seg size 29, 13470 merges
merged operations:
 insert 16085, delete mark 1, delete 0
discarded operations:
 insert 0, delete mark 0, delete 0
Hash table size 26925443, node heap has 12297 buffer(s)
88.49 hash searches/s, 299.95 non-hash searches/s
---
LOG
---
Log sequence number 26883102702
Log flushed up to   26883102702
Last checkpoint at  26883102692
0 pending log writes, 0 pending chkp writes
147530 log i/o's done, 0.17 log i/o's/second
----------------------
BUFFER POOL AND MEMORY
----------------------
Total memory allocated 13924155392; in additional pool allocated 0
Dictionary memory allocated 584219
Buffer pool size   830399
Free buffers       4746
Database pages     813356
Old database pages 300262
Modified db pages  1
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 325, not young 0
0.00 youngs/s, 0.00 non-youngs/s
Pages read 83323, created 730033, written 2387294
0.00 reads/s, 0.00 creates/s, 0.00 writes/s
Buffer pool hit rate 1000 / 1000, young-making rate 0 / 1000 not 0 / 1000
Pages read ahead 0.00/s, evicted without access 0.00/s, Random read ahead 0.00/s
LRU len: 813356, unzip_LRU len: 0
I/O sum[0]:cur[0], unzip sum[0]:cur[0]
--------------
ROW OPERATIONS
--------------
0 queries inside InnoDB, 0 queries in queue
1 read views open inside InnoDB
Main thread process no. 7755, id 1197041984, state: sleeping
Number of rows inserted 69343335, updated 755918, deleted 6235734, read 5140753915
0.00 inserts/s, 0.00 updates/s, 0.00 deletes/s, 542.41 reads/s
----------------------------
END OF INNODB MONITOR OUTPUT

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显示状态

Variable_name   Value
Aborted_clients 6941
Aborted_connects    39
Binlog_cache_disk_use   171
Binlog_cache_use    43567
Binlog_stmt_cache_disk_use  2
Binlog_stmt_cache_use   82079
Bytes_received  983
Bytes_sent  5749
Com_admin_commands  11
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Com_show_status 1
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Compression ON
Connections 29818
Created_tmp_disk_tables 0
Created_tmp_files   524
Created_tmp_tables  2
Delayed_errors  0
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Handler_commit  0
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Innodb_buffer_pool_read_ahead   20910
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Innodb_buffer_pool_read_requests    10304108333
Innodb_buffer_pool_reads    49001
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Innodb_buffer_pool_write_requests   617475366
Innodb_data_fsyncs  263503
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Innodb_data_read    1369460736
Innodb_data_reads   61692
Innodb_data_writes  619040
Innodb_data_written 100213573632
Innodb_dblwr_pages_written  2387449
Innodb_dblwr_writes 42845
Innodb_have_atomic_builtins ON
Innodb_log_waits    29
Innodb_log_write_requests   47769295
Innodb_log_writes   134764
Innodb_os_log_fsyncs    144634
Innodb_os_log_pending_fsyncs    0
Innodb_os_log_pending_writes    0
Innodb_os_log_written   21975030784
Innodb_page_size    16384
Innodb_pages_created    730033
Innodb_pages_read   83323
Innodb_pages_written    2387449
Innodb_row_lock_current_waits   0
Innodb_row_lock_time    779558
Innodb_row_lock_time_avg    3765
Innodb_row_lock_time_max    51611
Innodb_row_lock_waits   207
Innodb_rows_deleted 6235739
Innodb_rows_inserted    69343350
Innodb_rows_read    5143551347
Innodb_rows_updated 755920
Innodb_truncated_status_writes  0
Key_blocks_not_flushed  0
Key_blocks_unused   26792
Key_blocks_used 0
Key_read_requests   0
Key_reads   0
K

Answer 1

Rol*_*DBA 6

由于您正在运行 MySQL 5.5，您是否考虑过调整 InnoDB 以获得更好的性能？

MySQL 5.1 InnoDB 插件中添加了几个变量，这些变量现在是 MySQL 5.5 的原生变量。如果环境可以处理，它们通常有助于增加超线程并利用更多的 IOPS。在你的情况下，你应该能够。

我之前研究过 RDS 模型（请参阅我的帖子：本地数据库与 Amazon RDS）并且可以告诉您 RDS 在调整 InnoDB 方面不是很有帮助。你将不得不在这个问题上大放异彩。

当您启动 RDS 实例时，您可能使用了默认的数据库参数组

您应该能够为自己创建一个新的数据库参数组。当你到达这里时，设置以下内容：

innodb_read_io_threads：允许的最高值为 64。在 RDS 中，允许的最高值为 16。默认值为 4。
innodb_write_io_threads：允许的最高值为 64。在 RDS 中，允许的最高值为 16。默认值为 4。
innodb_thread_concurrency：默认值已经是 0。永远不要将此值设置为任何其他数字。

我建议这些是因为它们在 RDS 中是默认的，因为 innodb_read_io_threads 和 innodb_write_io_threads 太低了。此外，您的SHOW ENGINE INNODB STATUS\G

--------
FILE I/O
--------
I/O thread 0 state: waiting for i/o request (insert buffer thread)
I/O thread 1 state: waiting for i/o request (log thread)
I/O thread 2 state: waiting for i/o request (read thread)
I/O thread 3 state: waiting for i/o request (read thread)
I/O thread 4 state: waiting for i/o request (read thread)
I/O thread 5 state: waiting for i/o request (read thread)
I/O thread 6 state: waiting for i/o request (write thread)
I/O thread 7 state: waiting for i/o request (write thread)
I/O thread 8 state: waiting for i/o request (write thread)
I/O thread 9 state: waiting for i/o request (write thread)

Run Code Online (Sandbox Code Playgroud)

只显示每类 io 线程的默认值 4。

这是坏消息：要实施配置更改，一旦您创建了自己的数据库参数组，您必须从旧的 RDS 实例导出数据，使用新的数据库参数组创建一个新实例，然后重新加载。更详细...

创建自定义数据库参数组（称之为MySettings）
下载 RDS CLI 并使用您的 AWS 凭证设置配置文件
执行以下操作： ./rds-modify-db-parameter-group MySettings --parameters "name=innodb_read_io_threads,value=16,method=immediate"
使用数据库参数选项列表进行修改 MySettings
重启 MySQL RDS 实例

我希望这有帮助！！！

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