We've received 8 instances of signal 11 crashes since October 2021, all detailed in the attachment. The DB has crashed each time and come back online. Unable to replicate on our test/dev database currently.

Feb 22 09:53:13 <daemon.info> redcap-dbserver-prod-02 mariadbd: 220222 9:53:13 [ERROR] mysqld got signal 11 ;
Feb 22 09:53:13 <daemon.info> redcap-dbserver-prod-02 mariadbd: Server version: 10.5.13-MariaDB
Feb 22 09:53:13 <daemon.info> redcap-dbserver-prod-02 mariadbd: key_buffer_size=134217728
Feb 22 09:53:13 <daemon.info> redcap-dbserver-prod-02 mariadbd: read_buffer_size=131072
Feb 22 09:53:13 <daemon.info> redcap-dbserver-prod-02 mariadbd: max_used_connections=173
Feb 22 09:53:13 <daemon.info> redcap-dbserver-prod-02 mariadbd: max_threads=302
Feb 22 09:53:13 <daemon.info> redcap-dbserver-prod-02 mariadbd: thread_count=14
Feb 22 09:53:13 <daemon.info> redcap-dbserver-prod-02 mariadbd: Thread pointer: 0x7fbafc0008d8
Feb 22 09:53:13 <daemon.info> redcap-dbserver-prod-02 mariadbd: stack_bottom = 0x7fbb4d7f9c90 thread_stack 0x49000
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(my_print_stacktrace)[0x55d161720d6e]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(handle_fatal_signal)[0x55d161123367]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: sigaction.c:0(__restore_rt)[0x7fbe193aa630]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(st_join_table::save_explain_data(Explain_table_access*, unsigned long long, bool, st_join_table*))[0x55d160f64c4f]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(JOIN::save_explain_data_intern(Explain_query*, bool, bool, bool, char const*))[0x55d160f6678b]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(JOIN::save_explain_data(Explain_query*, bool, bool, bool, bool))[0x55d160f668f0]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(JOIN::build_explain())[0x55d160f66b4c]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(JOIN::optimize())[0x55d160f7c0b1]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(mysql_select(THD*, TABLE_LIST*, List<Item>&, Item*, unsigned int, st_order*, st_order*, Item*, st_order*, unsigned long long, select_result*, st_select_lex_unit*, st_select_lex*))[0x55d160f7c1c7]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(handle_select(THD*, LEX*, select_result*, unsigned long))[0x55d160f7ce34]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: /usr/sbin/mariadbd(+0x63b749)[0x55d160ddb749]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(mysql_execute_command(THD*))[0x55d160f2087d]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(mysql_parse(THD*, char*, unsigned int, Parser_state*, bool, bool))[0x55d160f22d15]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(dispatch_command(enum_server_command, THD*, char*, unsigned int, bool, bool))[0x55d160f255e5]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(do_command(THD*))[0x55d160f26d7f]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(do_handle_one_connection(CONNECT*, bool))[0x55d161013662]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(handle_one_connection)[0x55d161013934]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(MyCTX_nopad::finish(unsigned char*, unsigned int*))[0x55d16137291d]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: pthread_create.c:0(start_thread)[0x7fbe193a2ea5]
Feb 22 09:53:14 <daemon.info> redcap-dbserver-prod-02 mariadbd: ??:0(__clone)[0x7fbe188bdb0d]