hi all, I am executing a stored proc that has a top level cursor to loop over a user set, and then execute certain transactions for each user. After processing about 5 users, it always generates: ERROR 2013 (HY000): Lost connection to MySQL server during query. However, if I restart from the same user again, it processes that user, and then encounters the same error after about 5-6 users. The other interesting thing to note is that this failure occurs at different points inside the stored proc. In essence, there is no predictability to this situation.
On further debugging, we found the issue to be bringing the server down, the stack info for which we are listing below, along with the mysql.cnf properties. Any immediate help is greatly appreciated. stack info (This is after executing the command resolve_stack_dump -s /tmp/mysqld.sym -n mysqld.stack ) 0x8156750 handle_segfault + 416 0xf4f420 (?) 0x3e49a4 (?) 0x825587d _ZN11sp_rcontext13set_item_evalEP3THDjPP4Item16enum_field_types + 61 0x8252ba6 _ZN12sp_instr_set9exec_coreEP3THDPj + 54 0x8252940 _ZN13sp_lex_keeper23reset_lex_and_exec_coreEP3THDPjbP8sp_instr + 304 0x8252b5e _ZN12sp_instr_set7executeEP3THDPj + 46 0x82504f4 _ZN7sp_head7executeEP3THD + 644 0x825140f _ZN7sp_head17execute_procedureEP3THDP4ListI4ItemE + 1215 0x816ff85 _Z21mysql_execute_commandP3THD + 19413 0x8172880 _Z11mysql_parseP3THDPcj + 304 0x8169d03 _Z16dispatch_command19enum_server_commandP3THDPcj + 1139 0x816983d _Z10do_commandP3THD + 141 0x8168d48 handle_one_connection + 600 0xa1fb80 (?) 0x83d9ce (?) my.cnf configiration ------------------------------ #password = your_password port = 3306 socket = /var/lib/mysql/mysql.sock [mysqld] datadir=/data/mysqldata/ port = 3306 socket = /var/lib/mysql/mysql.sock skip-locking key_buffer = 200M max_allowed_packet = 16M table_cache = 512 sort_buffer_size = 2M read_buffer_size = 2M read_rnd_buffer_size = 8M myisam_sort_buffer_size = 4M thread_cache = 8 query_cache_size = 32M # Try number of CPU's*2 for thread_concurrency thread_concurrency = 4 default-table-type=innodb innodb_log_group_home_dir = /data/logs/ innodb_log_arch_dir = /data/logs/ innodb_buffer_pool_size = 512M innodb_additional_mem_pool_size = 20M innodb_log_file_size = 256M innodb_log_buffer_size = 8M innodb_flush_log_at_trx_commit = 1 innodb_lock_wait_timeout = 50 log_error log_slow_queries [mysqldump] quick max_allowed_packet = 16M [mysql] no-auto-rehash # Remove the next comment character if you are not familiar with SQL #safe-updates [isamchk] key_buffer = 256M sort_buffer_size = 256M read_buffer = 2M write_buffer = 2M [myisamchk] key_buffer = 256M sort_buffer_size = 256M read_buffer = 2M write_buffer = 2M [mysqlhotcopy] interactive-timeout Thank you sujay
