Should I increase my key_buffer_size?

I have 4 node and database has InnoDB tables. my key_buffer_size is 128M. Should i increase it in my system? My innodb_buffer_pool_size is 75G and innodb_log_buffer_size = 256M. Mem: 96688 92580 4107 0 116 8501 -/+ buffers/cache: 83962 12725 Swap: 10239 5104 5135 MariaDB [mydata]> SHOW STATUS LIKE "key%"; +------------------------+--------+ | Variable_name | Value | +------------------------+--------+ | Key_blocks_not_flushed | 0 | | Key_blocks_unused | 107171 | | Key_blocks_used | 4 | | Key_blocks_warm | 0 | | Key_read_requests | 25 | | Key_reads | 4 | | Key_write_requests | 14 | | Key_writes | 11 | +------------------------+--------+ 8 rows in set (0.00 sec) I got that error, one of my node closed so I have that question. I use 5.5.46-MariaDB-1~trusty wsrep_25.12.r4f8102 Thanks RECORD LOCKS space id 513 page no 16 n bits 296 index GEN_CLUST_INDEX of table mydata.user_counter trx id 65CFC8177 lock_mode X locks rec but not gap 161230 19:08:36 [ERROR] mysqld got signal 6 ; 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 http://kb.askmonty.org/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: 5.5.46-MariaDB-1~trusty-wsrep-log key_buffer_size=134217728 read_buffer_size=2097152 max_used_connections=809 max_threads=2002 thread_count=224 It is possible that mysqld could use up to key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 12467846 K bytes of memory Hope that's ok; if not, decrease some variables in the equation. Thread pointer: 0x0x7feb728c6000 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 = 0x7ff378886a00 thread_stack 0x48000 (my_addr_resolve failure: fork) /usr/sbin/mysqld(my_print_stacktrace+0x2e) [0x7ff37c2db1ae] /usr/sbin/mysqld(handle_fatal_signal+0x457) [0x7ff37bebffc7] /lib/x86_64-linux-gnu/libpthread.so.0(+0x10340) [0x7ff37a90e340] /lib/x86_64-linux-gnu/libc.so.6(gsignal+0x39) [0x7ff379f65cc9] /lib/x86_64-linux-gnu/libc.so.6(abort+0x148) [0x7ff379f690d8] /usr/sbin/mysqld(+0x2ded4e) [0x7ff37bcafd4e] /usr/sbin/mysqld(+0x835033) [0x7ff37c206033] /usr/sbin/mysqld(+0x83b811) [0x7ff37c20c811] /usr/sbin/mysqld(+0x83c35b) [0x7ff37c20d35b] /usr/sbin/mysqld(+0x75a2b2) [0x7ff37c12b2b2] /usr/sbin/mysqld(+0x75e7ad) [0x7ff37c12f7ad] /usr/sbin/mysqld(+0x729202) [0x7ff37c0fa202] /usr/sbin/mysqld(Rows_log_event::find_row(Relay_log_info const*)+0x665) [0x7ff37bfa0a45] /usr/sbin/mysqld(Update_rows_log_event::do_exec_row(Relay_log_info const*)+0x9c) [0x7ff37bfa0e8c] /usr/sbin/mysqld(Rows_log_event::do_apply_event(Relay_log_info const*)+0x25c) [0x7ff37bf944ac] /usr/sbin/mysqld(wsrep_apply_cb(void*, void const*, unsigned long, unsigned int, wsrep_trx_meta const*)+0x7ba) [0x7ff37be70afa] /usr/lib/galera/libgalera_smm.so(galera::TrxHandle::apply(void*, wsrep_cb_status (*)(void*, void const*, unsigned long, unsigned int, wsrep_trx_meta const*), wsrep_trx_meta const&) const+0xd8) [0x7ff377b188f8] /usr/lib/galera/libgalera_smm.so(+0x1df27d) [0x7ff377b4f27d] /usr/lib/galera/libgalera_smm.so(galera::ReplicatorSMM::apply_trx(void*, galera::TrxHandle*)+0xd2) [0x7ff377b51b32] /usr/lib/galera/libgalera_smm.so(galera::ReplicatorSMM::process_trx(void*, galera::TrxHandle*)+0x10e) [0x7ff377b5498e] /usr/lib/galera/libgalera_smm.so(galera::GcsActionSource::dispatch(void*, gcs_action const&, bool&)+0x1b8) [0x7ff377b33668] /usr/lib/galera/libgalera_smm.so(galera::GcsActionSource::process(void*, bool&)+0x58) [0x7ff377b33ef8] /usr/lib/galera/libgalera_smm.so(galera::ReplicatorSMM::async_recv(void*)+0x73) [0x7ff377b54ef3] /usr/lib/galera/libgalera_smm.so(galera_recv+0x18) [0x7ff377b634e8] /usr/sbin/mysqld(+0x4a0744) [0x7ff37be71744] /usr/sbin/mysqld(start_wsrep_THD+0x48e) [0x7ff37bcccc0e] /lib/x86_64-linux-gnu/libpthread.so.0(+0x8182) [0x7ff37a906182] /lib/x86_64-linux-gnu/libc.so.6(clone+0x6d) [0x7ff37a02947d] Trying to get some variables. Some pointers may be invalid and cause the dump to abort. Query (0x0): is an invalid pointer Connection ID (thread ID): 10 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=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. 161230 19:08:40 mysqld_safe Number of processes running now: 0 161230 19:08:40 mysqld_safe WSREP: not restarting wsrep node automatically 161230 19:08:40 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended