4:20 PM

 170209 16:13:05 [ERROR] 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.

 To report this bug, see https://mariadb.com/kb/en/reporting-bugs

 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.

 Server version: 10.1.18-MariaDB-1~xenial

 key_buffer_size=134217728

 read_buffer_size=2097152

 max_used_connections=12

 max_threads=202

 thread_count=9

 It is possible that mysqld could use up to

 key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 1376288 K  bytes of memory

 Hope that's ok; if not, decrease some variables in the equation.

 Thread pointer: 0x0x7f150cc49008

 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 = 0x7f15a774b0a8 thread_stack 0x48400

 /usr/sbin/mysqld(my_print_stacktrace+0x2e)[0x55e1f7a9062e]

 /usr/sbin/mysqld(handle_fatal_signal+0x2d5)[0x55e1f75df3d5]

 /lib/x86_64-linux-gnu/libpthread.so.0(+0x113d0)[0x7f15a5ebd3d0]

 /usr/sbin/mysqld(_ZN13MYSQL_BIN_LOG13mark_xid_doneEmb+0x8b)[0x55e1f769431b]

 /usr/sbin/mysqld(binlog_background_thread+0x2f3)[0x55e1f76948f3]

 /usr/sbin/mysqld(+0x705fb1)[0x55e1f774ffb1]

 /lib/x86_64-linux-gnu/libpthread.so.0(+0x76fa)[0x7f15a5eb36fa]

 /lib/x86_64-linux-gnu/libc.so.6(clone+0x6d)[0x7f15a555eb5d]

 Trying to get some variables.

 Some pointers may be invalid and cause the dump to abort.

 Query (0x0):

 Connection ID (thread ID): 3

 Status: NOT_KILLED

 Optimizer switch: index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=off

 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.

 Main process exited, code=exited, status=1/FAILURE

 Unit entered failed state.

 Failed with result 'exit-code'.