Crash during OPTIMIZE TABLE

00:10:26 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.
Please help us make Percona Server better by reporting any
bugs at http://bugs.percona.com/

key_buffer_size=536870912
read_buffer_size=262144
max_used_connections=699
max_threads=100020
thread_count=411
connection_count=408
It is possible that mysqld could use up to
key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 435 821 357 K bytes of memory
Hope that's ok; if not, decrease some variables in the equation.

Thread pointer: 0x7f08753e3000
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 = 7f0abcf07be0 thread_stack 0x40000
/usr/sbin/mysqld(my_print_stacktrace+0x3b)[0x8e81db]
/usr/sbin/mysqld(handle_fatal_signal+0x471)[0x65f461]
/lib64/libpthread.so.0(+0xf370)[0x7f2e59417370]
/usr/sbin/mysqld(_Z10key_unpackP6StringP5TABLEP6st_key+0x38)[0x645e98]
/usr/sbin/mysqld(_Z18print_keydup_errorP5TABLEP6st_keyPKci+0x82)[0x5a0242]
/usr/sbin/mysqld[0x9adfcc]
/usr/sbin/mysqld(_Z17mysql_alter_tableP3THDPcS1_P24st_ha_create_informationP10TABLE_LISTP10Alter_infojP8st_orderb+0x1e66)[0x73b266]
/usr/sbin/mysqld(_Z20mysql_recreate_tableP3THDP10TABLE_LISTb+0x17c)[0x73ca8c]
/usr/sbin/mysqld[0x81f41c]
/usr/sbin/mysqld(_ZN22Sql_cmd_optimize_table7executeEP3THD+0xde)[0x81fc9e]
/usr/sbin/mysqld(_Z21mysql_execute_commandP3THD+0xfda)[0x6e3b4a]
/usr/sbin/mysqld(_Z11mysql_parseP3THDPcjP12Parser_state+0x5b8)[0x6e9e78]
/usr/sbin/mysqld(_Z16dispatch_command19enum_server_commandP3THDPcj+0x1002)[0x6eb622]
/usr/sbin/mysqld(_Z26threadpool_process_requestP3THD+0x108)[0x77a8f8]
/usr/sbin/mysqld[0x77b6ee]
/usr/sbin/mysqld(pfs_spawn_thread+0x146)[0x983b46]
/lib64/libpthread.so.0(+0x7dc5)[0x7f2e5940fdc5]
/lib64/libc.so.6(clone+0x6d)[0x7f2e575e476d]

Trying to get some variables.
Some pointers may be invalid and cause the dump to abort.
Query (7f0b2662e010): is an invalid pointer
Connection ID (thread ID): 8249845
Status: NOT_KILLED

You may download the Percona Server operations manual by visiting
http://www.percona.com/software/percona-server/. You may find information
in the manual which will help you identify the cause of the crash.