電源障害とmysqlクラッシュ

Question

私はInnoDbエンジンでMySqlをしばらく使用しており、パフォーマンスにかなり満足しています。私は10のテーブルを持っていて、毎秒2回更新しています。最近停電があり、innodb_force_recoveryを少なくとも4に設定せずにデータベースを再起動できませんでした。しかし、壊れたテーブルを修正しようとすると、データベースが再びクラッシュします。私は最適化、チェック、分析などを試みましたが、すべてがクラッシュしました。 エラーログには次のようなメッセージが含まれています。

InnoDB：エラー：570ページログシーケンス番号7289495 InnoDB：今後です！現在のシステムログシーケンス番号5574939.

最終的に、特定のテーブルに関連するすべてのファイルを削除した後、mysqldump（innodb_force_recovery = 6）を使用してデータベースをダンプすることができました。それから、xamppを再インストールしてダンプを再ロードしました。これは、1つのテーブルだけを失って、私を立ち上げて、再び走った。

私の質問は、どのように1つのテーブルを破損させるとデータベース全体がクラッシュする可能性がありますか？

この問題が再び発生する危険性を最小限に抑える方法はありますか？停電に対する堅牢性を高めるための何らかの設定ですか？ 明らかなのは、複製されたバックアップデータベースを別のサーバに保存することですが、開発のテスト段階にあり、過度のように思えます。

ここに私が使用している設定ファイルがあります。

# Example MySQL config file for small systems. 
# 
# This is for a system with little memory (<= 64M) where MySQL is only used 
# from time to time and it's important that the mysqld daemon 
# doesn't use much resources. 
# 
# You can copy this file to 
# C:/xampp2/mysql/bin/my.cnf to set global options, 
# mysql-data-dir/my.cnf to set server-specific options (in this 
# installation this directory is C:/xampp2/mysql/data) or 
# ~/.my.cnf to set user-specific options. 
# 
# In this file, you can use all long options that a program supports. 
# If you want to know which options a program supports, run the program 
# with the "--help" option. 

# The following options will be passed to all MySQL clients 
[client] 
# password  = your_password 
port   = 3306 
socket   = "C:/xampp2/mysql/mysql.sock" 


# Here follows entries for some specific programs 

# The MySQL server 
[mysqld] 
port= 3306 
socket = "C:/xampp2/mysql/mysql.sock" 
basedir = "C:/xampp2/mysql" 
tmpdir = "C:/xampp2/tmp" 
datadir = "C:/xampp2/mysql/data" 
pid_file = "mysql.pid" 
# enable-named-pipe 
key_buffer = 16M 
max_allowed_packet = 1G 
sort_buffer_size = 512K 
net_buffer_length = 8K 
read_buffer_size = 256K 
read_rnd_buffer_size = 512K 
myisam_sort_buffer_size = 8M 
log_error = "mysql_error.log" 

# Change here for bind listening 
# bind-address="127.0.0.1" 
# bind-address = ::1   # for ipv6 

# Where do all the plugins live 
plugin_dir = "C:/xampp2/mysql/lib/plugin/" 

# Don't listen on a TCP/IP port at all. This can be a security enhancement, 
# if all processes that need to connect to mysqld run on the same host. 
# All interaction with mysqld must be made via Unix sockets or named pipes. 
# Note that using this option without enabling named pipes on Windows 
# (via the "enable-named-pipe" option) will render mysqld useless! 
# 
# commented in by lampp security 
#skip-networking 
#skip-federated 

# Replication Master Server (default) 
# binary logging is required for replication 
# log-bin deactivated by default since XAMPP 1.4.11 
#log-bin=mysql-bin 

# required unique id between 1 and 2^32 - 1 
# defaults to 1 if master-host is not set 
# but will not function as a master if omitted 
server-id = 1 

# Replication Slave (comment out master section to use this) 
# 
# To configure this host as a replication slave, you can choose between 
# two methods : 
# 
# 1) Use the CHANGE MASTER TO command (fully described in our manual) - 
# the syntax is: 
# 
# CHANGE MASTER TO MASTER_HOST=<host>, MASTER_PORT=<port>, 
# MASTER_USER=<user>, MASTER_PASSWORD=<password> ; 
# 
# where you replace <host>, <user>, <password> by quoted strings and 
# <port> by the master's port number (3306 by default). 
# 
# Example: 
# 
# CHANGE MASTER TO MASTER_HOST='125.564.12.1', MASTER_PORT=3306, 
# MASTER_USER='joe', MASTER_PASSWORD='secret'; 
# 
# OR 
# 
# 2) Set the variables below. However, in case you choose this method, then 
# start replication for the first time (even unsuccessfully, for example 
# if you mistyped the password in master-password and the slave fails to 
# connect), the slave will create a master.info file, and any later 
# change in this file to the variables' values below will be ignored and 
# overridden by the content of the master.info file, unless you shutdown 
# the slave server, delete master.info and restart the slaver server. 
# For that reason, you may want to leave the lines below untouched 
# (commented) and instead use CHANGE MASTER TO (see above) 
# 
# required unique id between 2 and 2^32 - 1 
# (and different from the master) 
# defaults to 2 if master-host is set 
# but will not function as a slave if omitted 
#server-id  = 2 
# 
# The replication master for this slave - required 
#master-host  = <hostname> 
# 
# The username the slave will use for authentication when connecting 
# to the master - required 
#master-user  = <username> 
# 
# The password the slave will authenticate with when connecting to 
# the master - required 
#master-password = <password> 
# 
# The port the master is listening on. 
# optional - defaults to 3306 
#master-port  = <port> 
# 
# binary logging - not required for slaves, but recommended 
#log-bin=mysql-bin 


# Point the following paths to different dedicated disks 
#tmpdir = "C:/xampp2/tmp" 
#log-update = /path-to-dedicated-directory/hostname 

# Uncomment the following if you are using BDB tables 
#bdb_cache_size = 4M 
#bdb_max_lock = 10000 

# Comment the following if you are using InnoDB tables 
#skip-innodb 
innodb_data_home_dir = "C:/xampp2/mysql/data" 
innodb_data_file_path = ibdata1:10M:autoextend 
innodb_log_group_home_dir = "C:/xampp2/mysql/data" 
#innodb_log_arch_dir = "C:/xampp2/mysql/data" 
## You can set .._buffer_pool_size up to 50 - 80 % 
## of RAM but beware of setting memory usage too high 
innodb_buffer_pool_size = 2G 
innodb_additional_mem_pool_size = 16M 
## Set .._log_file_size to 25 % of buffer pool size 
innodb_log_file_size = 50M 
innodb_log_buffer_size = 20M 
innodb_flush_log_at_trx_commit = 2 
innodb_lock_wait_timeout = 50 
innodb_buffer_pool_instances = 4 

## UTF 8 Settings 
#init-connect=\'SET NAMES utf8\' 
#collation_server=utf8_unicode_ci 
#character_set_server=utf8 
#skip-character-set-client-handshake 
#character_sets-dir="C:/xampp2/mysql/share/charsets" 

[mysqldump] 
quick 
max_allowed_packet = 16M 

[mysql] 
no-auto-rehash 
# Remove the next comment character if you are not familiar with SQL 
#safe-updates 

[isamchk] 
key_buffer = 20M 
sort_buffer_size = 20M 
read_buffer = 2M 
write_buffer = 2M 

[myisamchk] 
key_buffer = 20M 
sort_buffer_size = 20M 
read_buffer = 2M 
write_buffer = 2M 

[mysqlhotcopy] 
interactive-timeout 

Answer 1

InnoDBはデータの一貫性に関して非常に控えめです。予期せぬもの（チェックサム、ヘッダ値、何かが間違っている）をキャッチすると、意図的にデータが破損しないようにクラッシュします。

どのように「この問題が再び発生する危険性を最小限に抑える」？

innodb_flush_log_at_trx_commit,doublewriteなどの安全なデフォルトを維持することが最善の方法です。インターネットには、「MySQLをより速くする方法」についての無意味なアドバイスがたくさんありますが、それは価格が付いています。