我需要从 MySQL（运行 MariaDB）备份我的一个数据库。问题是，除了我所有其他可以完美备份的数据库之外，这个数据库在备份时会出现问题，并且每次我尝试备份时都会使服务器崩溃。
mysqldump shadygam_forum -u root -p > dump.sql
Enter password:
mysqldump: Got error: 2013: "Lost connection to MySQL server during query" when using LOCK TABLES
所以我查看了错误日志，发现/var/lib/mysql/myerrorlog.err
InnoDB: Error: tried to read 16384 bytes at offset 0 819200.
InnoDB: Was only able to read 0.
141219 4:32:54 InnoDB: Operating system error number 5 in a file operation.
InnoDB: Error number 5 means 'Input/output error'.
InnoDB: Some operating system error numbers are described at
InnoDB: http://dev.mysql.com/doc/refman/5.5/en/operating-system-error-codes.html
InnoDB: File operation call: 'read'.
InnoDB: Cannot continue operation.
141219 04:32:54 mysqld_safe Number of processes running now: 0
141219 04:32:54 mysqld_safe mysqld restarted
141219 4:32:54 InnoDB: The InnoDB memory heap is disabled
141219 4:32:54 InnoDB: Mutexes and rw_locks use GCC atomic builtins
141219 4:32:54 InnoDB: Compressed tables use zlib 1.2.3
141219 4:32:54 InnoDB: Using Linux native AIO
141219 4:32:54 InnoDB: Initializing buffer pool, size = 2.0G
141219 4:32:54 InnoDB: Completed initialization of buffer pool
141219 4:32:54 InnoDB: highest supported file format is Barracuda.
InnoDB: The log sequence number in ibdata files does not match
InnoDB: the log sequence number in the ib_logfiles!
141219 4:32:54 InnoDB: Database was not shut down normally!
InnoDB: Starting crash recovery.
InnoDB: Reading tablespace information from the .ibd files...
InnoDB: Restoring possible half-written data pages from the doublewrite
InnoDB: buffer...
141219 4:32:55 InnoDB: Waiting for the background threads to start
141219 4:32:56 Percona XtraDB (http://www.percona.com) 5.5.38-MariaDB-35.2 started; log sequence number 12116884277
141219 4:32:56 [Note] Plugin 'FEEDBACK' is disabled.
141219 4:32:56 [Note] Server socket created on IP: '0.0.0.0'.
141219 4:32:56 [ERROR] Missing system table mysql.proxies_priv; please run mysql_upgrade to create it
141219 4:32:56 [ERROR] Native table 'performance_schema'.'events_waits_current' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'events_waits_history' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'events_waits_history_long' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'setup_consumers' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'setup_instruments' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'setup_timers' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'performance_timers' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'threads' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'events_waits_summary_by_thread_by_event_name' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'events_waits_summary_by_instance' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'events_waits_summary_global_by_event_name' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'file_summary_by_event_name' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'file_summary_by_instance' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'mutex_instances' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'rwlock_instances' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'cond_instances' has the wrong structure
141219 4:32:56 [ERROR] Native table 'performance_schema'.'file_instances' has the wrong structure
141219 4:32:56 [ERROR] Incorrect definition of table mysql.event: expected column 'sql_mode' at position 14 to have type set('REAL_AS_FLOAT','PIPES_AS_CONCAT','ANSI_QUOTES','IGNORE_SPACE','IGNORE_BAD_TABLE_OPTIONS','ONLY_FULL_GROUP_BY','NO_UNSIGNED_SUBTRACTION','NO_DIR_IN_CREATE','POSTGRESQL','ORACLE','MSSQL','DB2','MAXDB','NO_KEY_OPTIONS','NO_TABLE_OPTIONS','NO_FIELD_OPTIONS','MYSQL323','MYSQL40','ANSI','NO_AUTO_VALUE_ON_ZERO','NO_BACKSLASH_ESCAPES','STRICT_TRANS_TABLES','STRICT_ALL_TABLES','NO_ZERO_IN_DATE','NO_ZERO_DATE','INVALID_DATES','ERROR_FOR_DIVISION_BY_ZERO','TRADITIONAL','NO_AUTO_CREATE_USER','HIGH_NOT_PRECEDENCE','NO_ENGINE_SUBSTITUTION','PAD_CHAR_TO_FULL_LENGTH'), found type set('REAL_AS_FLOAT','PIPES_AS_CONCAT','ANSI_QUOTES','IGNORE_SPACE','NOT_USED','ONLY_FULL_GROUP_BY','NO_UNSIGNED_SUBTRACTION','NO_DIR_IN_CREATE','POSTGRESQL','ORACLE','MSSQL','DB2','MAXDB','NO_KEY_OPTIONS','NO_TABLE_OPTIONS','NO_FIELD_OPTIONS','MYSQL323','MYSQL40','ANSI','NO_AUTO_VALUE_ON_ZERO','NO_BACKSLASH_ESCAPES','STRICT_TRANS_TABLES','STRICT_A
141219 4:32:56 [ERROR] Event Scheduler: An error occurred when initializing system tables. Disabling the Event Scheduler.
141219 4:32:56 [Note] /usr/sbin/mysqld: ready for connections.
Version: '5.5.39-MariaDB' socket: '/var/lib/mysql/mysql.sock' port: 3306 MariaDB Server
141219 4:32:59 [ERROR] mysqld: Table './shadygam_forum/xf_session' is marked as crashed and should be repaired
141219 4:32:59 [Warning] Checking table: './shadygam_forum/xf_session'
查看其中一些错误，我尝试了以下操作
mysql_upgrade -u root -p
它会检查所有的表，OK直到开始处理该数据库的表并崩溃。
.
.
.
phanime_xenForo.xf_user_upgrade_expired OK
phanime_xenForo.xf_user_upgrade_log OK
phanime_xenForo.xf_warning OK
phanime_xenForo.xf_warning_action OK
phanime_xenForo.xf_warning_action_trigger OK
phanime_xenForo.xf_warning_definition OK
phanime_xenForo.xf_widget OK
phanime_xenForo.xf_widgetframework_widget_page OK
shadygam_forum
mysqlcheck: Got error: 2013: Lost connection to MySQL server during query when executing 'CHECK TABLE ... FOR UPGRADE'
FATAL ERROR: Upgrade failed
因此我检查错误日志，发现是完全相同的错误。
所以我也尝试执行命令来修复shadygam_forum.xf_session表，像这样
REPAIR TABLE xf_session而在 shadygam_forum 数据库中，这也会导致服务器崩溃。