sbester@linux:~/server/5.0/mysql-standard-5.0.26-linux-i686-glibc23> tail ./data/linux.err -n 40 thd=0x8a9a350 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... Cannot determine thread, fp=0x4288b12c, backtrace may not be correct. Stack range sanity check OK, backtrace follows: 0x817adf8 handle_segfault + 356 0x838437f hp_delete_key + 115 0x8383d1d heap_write + 317 0x821f686 _ZN7ha_heap9write_rowEPc + 66 0x81c9b9f _Z9end_writeP4JOINP13st_join_tableb + 227 0x81c8ff1 _Z20evaluate_join_recordP4JOINP13st_join_tableiPc + 329 0x81c2b1a _Z10sub_selectP4JOINP13st_join_tableb + 270 0x81c8cb3 _Z9do_selectP4JOINP4ListI4ItemEP8st_tableP9Procedure + 275 0x81bdf76 _ZN4JOIN4execEv + 1366 0x81bf5c1 _Z12mysql_selectP3THDPPP4ItemP13st_table_listjR4ListIS1_ES2_jP8st_orderSB_S2_SB_mP13select_resultP18st_select_lex_unitP13st_sel + 305 0x81bb382 _Z13handle_selectP3THDP6st_lexP13select_resultm + 270 0x818fa2a _Z21mysql_execute_commandP3THD + 642 0x8196a02 _Z11mysql_parseP3THDPcj + 306 0x818e2a6 _Z16dispatch_command19enum_server_commandP3THDPcj + 1182 0x818ddcd _Z10do_commandP3THD + 129 0x818d4c4 handle_one_connection + 620 0x40040aa7 _end + 933727415 0x40175c2e _end + 934993470 New value of fp=(nil) failed sanity check, terminating stack trace! Please read http://dev.mysql.com/doc/mysql/en/Using_stack_trace.html and follow instructions on how to resolve the stack trace. Resolved stack trace is much more helpful in diagnosing the problem, so please do resolve it Trying to get some variables. Some pointers may be invalid and cause the dump to abort... thd->query at 0x8aa58a0 = select * from oom group by id thd->thread_id=2 The manual page at http://www.mysql.com/doc/en/Crashing.html contains information that should help you find out what is causing the crash. Number of processes running now: 0 061019 00:12:16 mysqld restarted