Ale*_*exD 5 mysql backup mysql-5.6 amazon-rds
我有一个使用 Amazon RDS MySQL 5.6.39 单可用区实例的简单 WordPress 网站。几乎每天晚上在备份窗口期间，RDS 实例都会崩溃并恢复，从而导致大约 20 分钟的停机时间。在备份窗口期间，几乎没有流量，只有监控系统在访问该站点。所有 RDS 参数均为默认值。我能做些什么吗？
RDS 控制台中的事件
May 24, 2018 at 17:31:00 PM UTC+0 Recovery of the DB instance is complete.
May 24, 2018 at 17:30:43 PM UTC+0 DB instance restarted
May 24, 2018 at 17:27:11 PM UTC+0 Recovery of the DB instance has
started. Recovery time will vary with the amount of data to be recovered.
May 24, 2018 at 17:24:21 PM UTC+0 Backing up DB instance
May 24, 2018 at 17:08:16 PM UTC+0 Backing up DB instance
有mysql-error.log
InnoDB: Warning: a long semaphore wait:
--Thread 47155048924928 has waited at trx0sys.ic line 103 for 1137.00 seconds the semaphore:
X-lock (wait_ex) on RW-latch at 0x2ae2f82536c0 created in file buf0buf.cc line 1069
a writer (thread id 47155048924928) has reserved it in mode wait exclusive
number of readers 1, waiters flag 0, lock_word: ffffffffffffffff
Last time read locked in file buf0flu.cc line 1056
Last time write locked in file /local/mysql-5.6.39.R1/storage/innobase/include/trx0sys.ic line 103
InnoDB: Warning: a long semaphore wait:
--Thread 47155007514368 has waited at trx0trx.cc line 193 for 1126.00 seconds the semaphore:
Mutex at 0x2ae31e7b9468 created file trx0sys.cc line 597, lock var 1
waiters flag 1
... dozens of the same warnings removed ....
InnoDB: ###### Starts InnoDB Monitor for 30 secs to print diagnostic info:
InnoDB: Pending preads 0, pwrites 0
=====================================
2018-05-24 17:27:56 2ae323403700 INNODB MONITOR OUTPUT
=====================================
Per second averages calculated from the last 11 seconds
-----------------
BACKGROUND THREAD
-----------------
srv_master_thread loops: 18166 srv_active, 0 srv_shutdown, 67861 srv_idle
srv_master_thread log flush and writes: 86026
----------
SEMAPHORES
----------
OS WAIT ARRAY INFO: reservation count 21968
OS WAIT ARRAY INFO: signal count 20419
Mutex spin waits 2746, rounds 128132, OS waits 3656
RW-shared spins 17908, rounds 538145, OS waits 12430
RW-excl spins 284, rounds 174171, OS waits 5727
Spin rounds per wait: 46.66 mutex, 30.05 RW-shared, 613.28 RW-excl
------------
TRANSACTIONS
------------
Trx id counter 46791208
Purge done for trx's n:o < 46791128 undo n:o < 0 state: running but idle
History list length 3134
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 0, not started
MySQL thread id 25541, OS thread handle 0x2ae32f78d700, query id 1747215 10.0.10.251 root init
SHOW /*!50000 ENGINE*/ INNODB STATUS
---TRANSACTION 0, not started
MySQL thread id 25526, OS thread handle 0x2ae32770b700, query id 1747126 10.0.10.251 root init
SHOW /*!50000 ENGINE*/ INNODB STATUS
---TRANSACTION 0, not started
MySQL thread id 25514, OS thread handle 0x2ae325aa2700, query id 1747061 10.0.10.251 root init
SHOW /*!50000 ENGINE*/ INNODB STATUS
---TRANSACTION 0, not started
mysql tables in use 1, locked 0
MySQL thread id 25505, OS thread handle 0x2ae327481700, query id 1747010 10.0.11.204 wordpress Sending data
SELECT meta_value FROM wp_sitemeta WHERE meta_key = 'site_name' AND site_id = 9
---TRANSACTION 0, not started
mysql tables in use 1, locked 0
MySQL thread id 25504, OS thread handle 0x2ae3275c6700, query id 1747004 10.0.11.44 wordpress Sending data
SELECT meta_value FROM wp_sitemeta WHERE meta_key = 'site_name' AND site_id = 9
---TRANSACTION 0, not started
mysql tables in use 1, locked 0
MySQL thread id 25503, OS thread handle 0x2ae325ba6700, query id 1746998 10.0.11.44 wordpress Sending data
SELECT meta_value FROM wp_sitemeta WHERE meta_key = 'site_name' AND site_id = 9
---TRANSACTION 0, not started
mysql tables in use 1, locked 0
MySQL thread id 25502, OS thread handle 0x2ae32591c700, query id 1746992 10.0.11.204 wordpress Sending data
SELECT meta_value FROM wp_sitemeta WHERE meta_key = 'site_name' AND site_id = 9
---TRANSACTION 0, not started
mysql tables in use 1, locked 0
MySQL thread id 25501, OS thread handle 0x2ae2dbfe7700, query id 1746986 10.0.11.204 wordpress Sending data
SELECT meta_value FROM wp_sitemeta WHERE meta_key = 'site_name' AND site_id = 9
---TRANSACTION 0, not started
mysql tables in use 1, locked 0
MySQL thread id 25500, OS thread handle 0x2ae3217cf700, query id 1746980 10.0.11.44 wordpress Sending data
SELECT meta_value FROM wp_sitemeta WHERE meta_key = 'site_name' AND site_id = 9
---TRANSACTION 0, not started
MySQL thread id 25499, OS thread handle 0x2ae3276ca700, query id 1746974 10.0.10.251 root init
SHOW /*!50000 ENGINE*/ INNODB STATUS
---TRANSACTION 0, not started
mysql tables in use 1, locked 0
MySQL thread id 25498, OS thread handle 0x2ae323fcf700, query id 1746971 10.0.11.204 wordpress Sending data
SELECT meta_value FROM wp_sitemeta WHERE meta_key = 'site_name' AND site_id = 9
---TRANSACTION 0, not started
mysql tables in use 1, locked 0
MySQL thread id 25497, OS thread handle 0x2ae327544700, query id 1746965 10.0.11.44 wordpress Sending data
SELECT meta_value FROM wp_sitemeta WHERE meta_key = 'site_name' AND site_id = 9
---TRANSACTION 0, not started estimating records in index range
mysql tables in use 1, locked 0
MySQL thread id 25495, OS thread handle 0x2ae325ae3700, query id 1746953 10.0.11.204 wordpress statistics
SELECT wp_site.id FROM wp_site WHERE wp_site.domain IN ( 'www.domain.com.au', 'domain.com.au', 'com.au', 'au' ) AND wp_site.path IN ( '/wp-content/', '/' ) ORDER BY CHAR_LENGTH(wp_site.domain) DESC, CHAR_LENGTH(wp_site.path) DESC
---TRANSACTION 0, not started estimating records in index range
mysql tables in use 1, locked 0
MySQL thread id 25494, OS thread handle 0x2ae3274c2700, query id 1746952 10.0.11.204 wordpress statistics
SELECT wp_site.id FROM wp_site WHERE wp_site.domain IN ( 'www.domain.com.au', 'domain.com.au', 'com.au', 'au' ) AND wp_site.path IN ( '/wp-content/', '/' ) ORDER BY CHAR_LENGTH(wp_site.domain) DESC, CHAR_LENGTH(wp_site.path) DESC
---TRANSACTION 0, not started
mysql tables in use 1, locked 0
MySQL thread id 25493, OS thread handle 0x2ae32f440700, query id 1746941 10.0.11.204 wordpress Sending data
SELECT meta_value FROM wp_sitemeta WHERE meta_key = 'site_name' AND site_id = 10
---TRANSACTION 0, not started
mysql tables in use 1, locked 0
MySQL thread id 25492, OS thread handle 0x2ae327503700, query id 1746935 10.0.11.44 wordpress Sending data
SELECT meta_value FROM wp_sitemeta WHERE meta_key = 'site_name' AND site_id = 9
---TRANSACTION 0, not started
mysql tables in use 1, locked 0
MySQL thread id 25491, OS thread handle 0x2ae32599e700, query id 1746929 10.0.11.44 wordpress Sending data
SELECT meta_value FROM wp_sitemeta WHERE meta_key = 'site_name' AND site_id = 9
---TRANSACTION 0, not started
mysql tables in use 1, locked 0
MySQL thread id 25490, OS thread handle 0x2ae323f4d700, query id 1746923 10.0.11.204 wordpress Sending data
SELECT meta_value FROM wp_sitemeta WHERE meta_key = 'site_name' AND site_id = 10
---TRANSACTION 0, not started estimating records in index range
mysql tables in use 1, locked 0
MySQL thread id 25486, OS thread handle 0x2ae2dbf65700, query id 1746899 10.0.11.204 wordpress statistics
SELECT wp_site.id FROM wp_site WHERE wp_site.domain IN ( 'www.domain.com.au', 'domain.com.au', 'com.au', 'au' ) AND wp_site.path IN ( '/wp-content/', '/' ) ORDER BY CHAR_LENGTH(wp_site.domain) DESC, CHAR_LENGTH(wp_site.path) DESC
---TRANSACTION 0, not started
mysql tables in use 1, locked 0
MySQL thread id 25484, OS thread handle 0x2ae323f8e700, query id 1746887 10.0.11.44 wordpress Sending data
SELECT meta_value FROM wp_sitemeta WHERE meta_key = 'site_name' AND site_id = 9
---TRANSACTION 46791168, not started
MySQL thread id 25481, OS thread handle 0x2ae323f0c700, query id 1746869 10.0.11.204 wordpress
---TRANSACTION 46791135, not started
MySQL thread id 25479, OS thread handle 0x2ae323e49700, query id 1746831 10.0.11.204 wordpress checking permissions
SHOW FULL COLUMNS FROM `wp_32_options`
---TRANSACTION 46791160, not started
MySQL thread id 25480, OS thread handle 0x2ae32170c700, query id 1746856 10.0.11.44 wordpress checking permissions
SHOW FULL COLUMNS FROM `wp_32_options`
---TRANSACTION 46791132, not started
MySQL thread id 25478, OS thread handle 0x2ae327607700, query id 1746816 10.0.11.44 wordpress checking permissions
SHOW FULL COLUMNS FROM `wp_32_options`
---TRANSACTION 46791129, not started
MySQL thread id 25477, OS thread handle 0x2ae32778d700, query id 1746807 10.0.11.44 wordpress checking permissions
SHOW FULL COLUMNS FROM `wp_32_options`
---TRANSACTION 46791122, not started
MySQL thread id 1, OS thread handle 0x2ae2d8944700, query id 1747217 localhost 127.0.0.1 rdsadmin init
SELECT count(*) from mysql.rds_history WHERE action = 'disable set master' GROUP BY action_timestamp,called_by_user,action,mysql_version,master_host,master_port,master_user,master_log_file ,master_log_pos,master_ssl ORDER BY action_timestamp LIMIT 1
--------
FILE I/O
--------
I/O thread 0 state: waiting for completed aio requests (insert buffer thread)
I/O thread 1 state: waiting for completed aio requests (log thread)
I/O thread 2 state: waiting for completed aio requests (read thread)
I/O thread 3 state: waiting for completed aio requests (read thread)
I/O thread 4 state: waiting for completed aio requests (read thread)
I/O thread 5 state: waiting for completed aio requests (read thread)
I/O thread 6 state: waiting for completed aio requests (write thread)
I/O thread 7 state: waiting for completed aio requests (write thread)
I/O thread 8 state: waiting for completed aio requests (write thread)
I/O thread 9 state: waiting for completed aio requests (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
60616 OS file reads, 356399 OS file writes, 165396 OS fsyncs
0.00 reads/s, 0 avg bytes/read, 0.00 writes/s, 0.00 fsyncs/s
-------------------------------------
INSERT BUFFER AND ADAPTIVE HASH INDEX
-------------------------------------
Ibuf: size 1, free list len 3, seg size 5, 66 merges
merged operations:
insert 199, delete mark 0, delete 0
discarded operations:
insert 0, delete mark 0, delete 0
Hash table size 1236953, node heap has 4034 buffer(s)
0.00 hash searches/s, 0.55 non-hash searches/s
---
LOG
---
Log sequence number 8176212174
Log flushed up to 8176212174
Pages flushed up to 8176212174
Last checkpoint at 8176212174
0 pending log writes, 0 pending chkp writes
129212 log i/o's done, 0.00 log i/o's/second
----------------------
BUFFER POOL AND MEMORY
----------------------
Total memory allocated 639598592; in additional pool allocated 0
Dictionary memory allocated 1612053
Buffer pool size 38144
Free buffers 1024
Database pages 33086
Old database pages 12193
Modified db pages 0
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 223420, not young 5361756
0.00 youngs/s, 0.00 non-youngs/s
Pages read 59989, created 131, written 218511
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: 33086, unzip_LRU len: 0
I/O sum[0]:cur[1], unzip sum[0]:cur[0]
--------------
ROW OPERATIONS
--------------
0 queries inside InnoDB, 0 queries in queue
19 read views open inside InnoDB
Main thread process no. 3409, id 47155039454976, state: sleeping
Number of rows inserted 11395, updated 88770, deleted 4851, read 3252049111
0.00 inserts/s, 0.00 updates/s, 0.00 deletes/s, 1.09 reads/s
----------------------------
END OF INNODB MONITOR OUTPUT
============================
=====================================
2018-05-24 17:28:02 2ae323403700 INNODB MONITOR OUTPUT
=====================================
Per second averages calculated from the last 2 seconds
-----------------
BACKGROUND THREAD
-----------------
srv_master_thread loops: 18166 srv_active, 0 srv_shutdown, 67866 srv_idle
srv_master_thread log flush and writes: 86030
----------
SEMAPHORES
----------
OS WAIT ARRAY INFO: reservation count 21977
OS WAIT ARRAY INFO: signal count 20424
Mutex spin waits 2790, rounds 128767, OS waits 3665
RW-shared spins 17908, rounds 538145, OS waits 12430
RW-excl spins 284, rounds 174171, OS waits 5727
Spin rounds per wait: 46.15 mutex, 30.05 RW-shared, 613.28 RW-excl
------------
TRANSACTIONS
------------
Trx id counter 46791224
Purge done for trx's n:o < 46791128 undo n:o < 0 state: running but idle
History list length 3134
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 46791202, not started
MySQL thread id 25536, OS thread handle 0x2ae32f648700, query id 1747187 10.0.11.44 wordpress
---TRANSACTION 46791169, not started
MySQL thread id 25537, OS thread handle 0x2ae32f689700, query id 1747193 10.0.11.204 wordpress
---TRANSACTION 46791172, not started
MySQL thread id 25538, OS thread handle 0x2ae32f6ca700, query id 1747199 10.0.11.204 wordpress
---TRANSACTION 46791186, not started
MySQL thread id 25540, OS thread handle 0x2ae32f74c700, query id 1747211 10.0.11.44 wordpress
---TRANSACTION 46791180, not started
MySQL thread id 25539, OS thread handle 0x2ae32f70b700, query id 1747205 10.0.11.204 wordpress
---TRANSACTION 46791195, not started
MySQL thread id 25535, OS thread handle 0x2ae32f607700, query id 1747181 10.0.11.204 wordpress
---TRANSACTION 46791207, not started
MySQL thread id 25534, OS thread handle 0x2ae32f5c6700, query id 1747175 10.0.11.44 wordpress
---TRANSACTION 46791171, not started
MySQL thread id 25533, OS thread handle 0x2ae32f585700, query id 1747169 10.0.11.44 wordpress
---TRANSACTION 46791174, not started
MySQL thread id 25532, OS thread handle 0x2ae32f544700, query id 1747163 10.0.11.204 wordpress
---TRANSACTION 46791187, not started
MySQL thread id 25531, OS thread handle 0x2ae32f503700, query id 1747157 10.0.11.204 wordpress
---TRANSACTION 46791176, not started
MySQL thread id 25530, OS thread handle 0x2ae32f4c2700, query id 1747150 10.0.11.44 wordpress
---TRANSACTION 46791201, not started
MySQL thread id 25529, OS thread handle 0x2ae2d89c7700, query id 1747144 10.0.11.44 wordpress
---TRANSACTION 46791205, not started
MySQL thread id 25528, OS thread handle 0x2ae325859700, query id 1747138 10.0.11.44 wordpress
---TRANSACTION 46791204, not started
MySQL thread id 25527, OS thread handle 0x2ae3216cb700, query id 1747132 10.0.11.44 wordpress
---TRANSACTION 46791203, not started
MySQL thread id 25525, OS thread handle 0x2ae325b65700, query id 1747123 10.0.11.204 wordpress
---TRANSACTION 46791200, not started
MySQL thread id 25524, OS thread handle 0x2ae2dbfa6700, query id 1747116 10.0.11.204 wordpress
---TRANSACTION 46791182, not started
MySQL thread id 25523, OS thread handle 0x2ae3258db700, query id 1747110 10.0.11.204 wordpress
---TRANSACTION 46791173, not started
MySQL thread id 25522, OS thread handle 0x2ae32774c700, query id 1747104 10.0.11.44 wordpress
---TRANSACTION 46791181, not started
MySQL thread id 25521, OS thread handle 0x2ae2d8a49700, query id 1747098 10.0.11.44 wordpress
---TRANSACTION 46791177, not started
MySQL thread id 25520, OS thread handle 0x2ae323ecb700, query id 1747092 10.0.11.44 wordpress
---TRANSACTION 46791191, not started
MySQL thread id 25519, OS thread handle 0x2ae3277ce700, query id 1747086 10.0.11.44 wordpress
---TRANSACTION 46791189, not started
MySQL thread id 25518, OS thread handle 0x2ae321649700, query id 1747080 10.0.11.204 wordpress
---TRANSACTION 46791199, not started
MySQL thread id 25516, OS thread handle 0x2ae325be7700, query id 1747073 10.0.11.204 wordpress
---TRANSACTION 46791185, not started
MySQL thread id 25515, OS thread handle 0x2ae327440700, query id 1747067 10.0.11.204 wordpress
---TRANSACTION 46791194, not started
MySQL thread id 25513, OS thread handle 0x2ae32174d700, query id 1747058 10.0.11.44 wordpress
---TRANSACTION 46791206, not started
MySQL thread id 25512, OS thread handle 0x2ae32168a700, query id 1747057 10.0.11.44 wordpress
---TRANSACTION 46791175, not started
MySQL thread id 25511, OS thread handle 0x2ae325a61700, query id 1747046 10.0.11.204 wordpress
---TRANSACTION 46791183, not started
MySQL thread id 25510, OS thread handle 0x2ae32589a700, query id 1747040 10.0.11.204 wordpress
---TRANSACTION 46791190, not started
MySQL thread id 25508, OS thread handle 0x2ae3259df700, query id 1747034 10.0.11.44 wordpress
---TRANSACTION 46791178, not started
MySQL thread id 25509, OS thread handle 0x2ae32f481700, query id 1747033 10.0.11.44 wordpress
---TRANSACTION 46791196, not started
MySQL thread id 25507, OS thread handle 0x2ae327689700, query id 1747022 10.0.11.204 wordpress
---TRANSACTION 46791193, not started
MySQL thread id 25506, OS thread handle 0x2ae323e8a700, query id 1747016 10.0.11.204 wordpress
---TRANSACTION 46791210, not started
MySQL thread id 25505, OS thread handle 0x2ae327481700, query id 1747010 10.0.11.204 wordpress
---TRANSACTION 46791213, not started
MySQL thread id 25504, OS thread handle 0x2ae3275c6700, query id 1747004 10.0.11.44 wordpress
---TRANSACTION 46791215, not started
MySQL thread id 25503, OS thread handle 0x2ae325ba6700, query id 1746998 10.0.11.44 wordpress
---TRANSACTION 46791208, not started
MySQL thread id 25502, OS thread handle 0x2ae32591c700, query id 1746992 10.0.11.204 wordpress
---TRANSACTION 46791214, not started
MySQL thread id 25501, OS thread handle 0x2ae2dbfe7700, query id 1746986 10.0.11.204 wordpress
---TRANSACTION 46791216, not started
MySQL thread id 25500, OS thread handle 0x2ae3217cf700, query id 1746980 10.0.11.44 wordpress
---TRANSACTION 0, not started
MySQL thread id 25499, OS thread handle 0x2ae3276ca700, query id 1746974 10.0.10.251 root
---TRANSACTION 46791218, not started
MySQL thread id 25498, OS thread handle 0x2ae323fcf700, query id 1746971 10.0.11.204 wordpress
---TRANSACTION 46791219, not started
MySQL thread id 25497, OS thread handle 0x2ae327544700, query id 1746965 10.0.11.44 wordpress
---TRANSACTION 46791197, not started
MySQL thread id 25496, OS thread handle 0x2ae2d8985700, query id 1746959 10.0.11.44 wordpress
---TRANSACTION 46791212, not started
MySQL thread id 25493, OS thread handle 0x2ae32f440700, query id 1746941 10.0.11.204 wordpress
---TRANSACTION 46791209, not started
MySQL thread id 25492, OS thread handle 0x2ae327503700, query id 1746935 10.0.11.44 wordpress
---TRANSACTION 46791220, not started
MySQL thread id 25491, OS thread handle 0x2ae32599e700, query id 1746929 10.0.11.44 wordpress
---TRANSACTION 46791211, not started
MySQL thread id 25490, OS thread handle 0x2ae323f4d700, query id 1746923 10.0.11.204 wordpress
---TRANSACTION 46791198, not started
MySQL thread id 25489, OS thread handle 0x2ae32595d700, query id 1746917 10.0.11.44 wordpress
---TRANSACTION 46791184, not started
MySQL thread id 25488, OS thread handle 0x2ae327648700, query id 1746916 10.0.11.44 wordpress
---TRANSACTION 46791170, not started
MySQL thread id 25487, OS thread handle 0x2ae327585700, query id 1746905 10.0.11.204 wordpress
---TRANSACTION 46791179, not started
MySQL thread id 25485, OS thread handle 0x2ae2d8a08700, query id 1746893 10.0.11.204 wordpress
---TRANSACTION 46791217, not started
MySQL thread id 25484, OS thread handle 0x2ae323f8e700, query id 1746887 10.0.11.44 wordpress
---TRANSACTION 46791192, not started
MySQL thread id 25483, OS thread handle 0x2ae325a20700, query id 1746881 10.0.11.204 wordpress
---TRANSACTION 46791188, not started
MySQL thread id 25482, OS thread handle 0x2ae32178e700, query id 1746875 10.0.11.44 wordpress
---TRANSACTION 46791168, not started
MySQL thread id 25481, OS thread handle 0x2ae323f0c700, query id 1746869 10.0.11.204 wordpress
---TRANSACTION 46791135, not started
MySQL thread id 25479, OS thread handle 0x2ae323e49700, query id 1746831 10.0.11.204 wordpress
---TRANSACTION 46791160, not started
MySQL thread id 25480, OS thread handle 0x2ae32170c700, query id 1746856 10.0.11.44 wordpress
---TRANSACTION 46791132, not started
MySQL/MariaDB 中的所有表都需要位于 InnoDB/XtraDB 中。
Amazon RDS 文档指出了MySQL和MariaDB的情况。
如果在快照期间大量使用任何 MyISAM 或 Aria 表，则快照可能会出现问题。MyISAM 和 Aria 既不是事务安全的，也不是崩溃安全的。
除非您可以确保在所有 MyISAM/Aria 表上运行FLUSH TABLES WITH READ LOCK;（保证没有写入流量和表锁定）并启动手动快照，否则您将遇到快照问题和崩溃情况，就像您所经历的那样。
我可以看到 MyISAM 的锁定方案（锁定粒度是表）干扰回滚的事务，并且 RDS 尝试独立于存储引擎行为执行自己的锁定。为了让 RDS 支持事务和时间点恢复，必须解决这些问题。
希望您已经将少数几个 MyISAM 表转换为 InnoDB后，不会再看到任何崩溃。