Hi, Running a mysqltuner.pl scan tells the following: [--] Up for: 6d 15h 31m 3s (139M q [242.402 qps], 2M conn, TX: 427B, RX: 16B) [--] Reads / Writes: 95% / 5% [--] Total buffers: 2.0G global + 2.3M per thread (175 max threads) [OK] Maximum possible memory usage: 2.4G (31% of installed RAM) However , it seems to be using more than what mysqltuner reports (3.3G now): [~]# ps -eo comm,rss|awk '{arr[$1]+=$2} END {for (i in arr) {print arr[i]/1024, i}}'|grep -v '^0 '|grep mysqld 3314.3 mysqld my.cnf: [mysqld] user = mysql extra_port = 3308 default_storage_engine = MyISAM sql-mode = NO_ENGINE_SUBSTITUTION # DATA STORAGE # datadir = /databases/mysql # MariaDB # thread_handling = pool-of-threads optimizer_switch ='mrr=on' optimizer_switch ='mrr_sort_keys=on' optimizer_switch ='mrr_cost_based=off' optimizer_switch ='join_cache_incremental=on' optimizer_switch ='join_cache_hashed=on' optimizer_switch ='join_cache_bka=on' mrr_buffer_size = 1M aria_pagecache_buffer_size = 128M aria_sort_buffer_size = 128M key_cache_segments = 8 # MyISAM # key_buffer_size = 256M myisam_recover = BACKUP,FORCE myisam_sort_buffer_size = 128M group_concat_max_len = 4096 max_seeks_for_key = 1000 #myisam_use_mmap = 1 # SAFETY # max_allowed_packet = 32M max_connect_errors = 1000 local-infile = 0 # CACHES AND LIMITS # tmp_table_size = 128M max_heap_table_size = 128M query_cache_type = 1 query_cache_size = 128M query_cache_limit = 1M query_cache_min_res_unit = 2K max_connections = 175 max_user_connections = 75 thread_cache_size = 32 open_files_limit = 50K table_definition_cache = 10K table_open_cache = 40K join_buffer_size = 1M sort_buffer_size = 512K read_buffer_size = 256K read_rnd_buffer_size = 256K # INNODB # sysdate_is_now = 1 innodb = FORCE innodb_strict_mode = 1 innodb_flush_method = O_DIRECT innodb_log_files_in_group = 2 innodb_log_file_size = 256M innodb_flush_log_at_trx_commit = 2 innodb_file_per_table = 1 innodb_buffer_pool_size = 1536M innodb_read_io_threads = 4 innodb_write_io_threads = 4 innodb_io_capacity = 400 # LOGGING # slow_query_log = 1 long_query_time = 5 connect_timeout=30 interactive_timeout=120 wait_timeout=120 Is this some memory leak problem , problems with the script or normal behavior ? Thank you in advance, Alexandru