>>> Error log from MySql server ,Starts here 11:12:30 UTC - mysqld got signal 11 ; This could be because you hit a bug. It is also possible that this binary or one of the libraries it was linked against is corrupt, improperly built, or misconfigured. This error can also be caused by malfunctioning hardware. We will try our best to scrape up some info that will hopefully help diagnose the problem, but since we have already crashed, something is definitely wrong and this may fail. key_buffer_size=2097152 read_buffer_size=2097152 max_used_connections=2 max_threads=300 thread_count=2 connection_count=2 It is possible that mysqld could use up to key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 1234902 K bytes of memory Hope that's ok; if not, decrease some variables in the equation. Thread pointer: 0x3255bb0 Attempting backtrace. You can use the following information to find out where mysqld died. If you see no messages after this, something went terribly wrong... stack_bottom = 7f60b4345e48 thread_stack 0x40000 /usr/sbin/mysqld(my_print_stacktrace+0x35)[0x8bfd45] /usr/sbin/mysqld(handle_fatal_signal+0x4a4)[0x65b074] /lib64/libpthread.so.0[0x32c500f4c0] /lib64/libc.so.6[0x32c4d205fa] /usr/sbin/mysqld[0x8ef339] /usr/sbin/mysqld[0x8f01c0] /usr/sbin/mysqld[0x72218a] /usr/sbin/mysqld(_Z17mysql_alter_tableP3THDPcS1_P24st_ha_create_informationP10TABLE_LISTP10Alter_infojP8st_orderb+0x2175)[0x724615] /usr/sbin/mysqld(_ZN19Sql_cmd_alter_table7executeEP3THD+0x479)[0x807149] /usr/sbin/mysqld(_Z21mysql_execute_commandP3THD+0xdf1)[0x6d3b91] /usr/sbin/mysqld(_Z11mysql_parseP3THDPcjP12Parser_state+0x32f)[0x6d7a5f] /usr/sbin/mysqld(_Z16dispatch_command19enum_server_commandP3THDPcj+0xe28)[0x6d8978] /usr/sbin/mysqld(_Z24do_handle_one_connectionP3THD+0xcf)[0x6a682f] /usr/sbin/mysqld(handle_one_connection+0x47)[0x6a6957] /lib64/libpthread.so.0[0x32c50077e1] /lib64/libc.so.6(clone+0x6d)[0x32c4ce153d] Trying to get some variables. Some pointers may be invalid and cause the dump to abort. Query (7f6040004c00): is an invalid pointer Connection ID (thread ID): 2 Status: NOT_KILLED The manual page at http://dev.mysql.com/doc/mysql/en/crashing.html contains information that should help you find out what is causing the crash. 130806 16:42:30 mysqld_safe Number of processes running now: 0 130806 16:42:30 mysqld_safe mysqld restarted 2013-08-06 16:42:30 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details). 2013-08-06 16:42:30 9640 [Note] InnoDB: The InnoDB memory heap is disabled 2013-08-06 16:42:30 9640 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins 2013-08-06 16:42:30 9640 [Note] InnoDB: Compressed tables use zlib 1.2.3 2013-08-06 16:42:30 9640 [Note] InnoDB: CPU does not support crc32 instructions 2013-08-06 16:42:30 9640 [Note] InnoDB: Using Linux native AIO 2013-08-06 16:42:30 9640 [Note] InnoDB: Initializing buffer pool, size = 1.0G 2013-08-06 16:42:30 9640 [Note] InnoDB: Completed initialization of buffer pool 2013-08-06 16:42:30 9640 [Note] InnoDB: Highest supported file format is Barracuda. 2013-08-06 16:42:30 9640 [Note] InnoDB: Log scan progressed past the checkpoint lsn 3781199717 2013-08-06 16:42:30 9640 [Note] InnoDB: Database was not shutdown normally! 2013-08-06 16:42:30 9640 [Note] InnoDB: Starting crash recovery. 2013-08-06 16:42:30 9640 [Note] InnoDB: Reading tablespace information from the .ibd files... 2013-08-06 16:42:30 9640 [Note] InnoDB: Restoring possible half-written data pages 2013-08-06 16:42:30 9640 [Note] InnoDB: from the doublewrite buffer... InnoDB: Doing recovery: scanned up to log sequence number 3781239176 2013-08-06 16:42:30 9640 [Note] InnoDB: Starting an apply batch of log records to the database... InnoDB: Progress in percent: 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 InnoDB: Apply batch completed 2013-08-06 16:42:31 9640 [Note] InnoDB: 128 rollback segment(s) are active. 2013-08-06 16:42:31 9640 [Note] InnoDB: Waiting for purge to start 2013-08-06 16:42:31 9640 [Note] InnoDB: 1.2.10 started; log sequence number 3781239176 2013-08-06 16:42:31 9640 [Note] Server hostname (bind-address): '*'; port: 5610 2013-08-06 16:42:31 9640 [Note] IPv6 is available. 2013-08-06 16:42:31 9640 [Note] - '::' resolves to '::'; 2013-08-06 16:42:31 9640 [Note] Server socket created on IP: '::'. 2013-08-06 16:42:31 9640 [Warning] 'proxies_priv' entry '@ root@mysql5610db.qa.aps.net' ignored in --skip-name-resolve mode. 2013-08-06 16:42:31 9640 [Note] Event Scheduler: Loaded 0 events 2013-08-06 16:42:31 9640 [Note] /usr/sbin/mysqld: ready for connections. Version: '5.6.10-log' socket: '/db_5610/MySql_5.6.10/mysql_5610.sock' port: 5610 MySQL Community Server (GPL) <<< Error log from MySql server ,Ends here