MySQL tuning memory

I have some MySQL problems, I am not sure how to tune memory settings From mysqltuner.pl: >> MySQLTuner 1.3.0 - Major Hayden >> Bug reports, feature requests, and downloads at [url=http://mysqltuner.com/]MySQLTuner-perl by major >> Run with '--help' for additional options and output filtering [OK] Currently running supported MySQL version 5.6.16-log [OK] Operating on 64-bit architecture -------- Storage Engine Statistics ------------------------------------------- [--] Status: +ARCHIVE +BLACKHOLE +CSV -FEDERATED +InnoDB +MRG_MYISAM [--] Data in MyISAM tables: 7M (Tables: 61) [--] Data in InnoDB tables: 84M (Tables: 2251) [--] Data in PERFORMANCE_SCHEMA tables: 0B (Tables: 52) [!!] Total fragmented tables: 33 -------- Security Recommendations ------------------------------------------- [OK] All database users have passwords assigned -------- Performance Metrics ------------------------------------------------- [--] Up for: 11d 0h 57m 2s (4M q [4.870 qps], 92K conn, TX: 11B, RX: 1B) [--] Reads / Writes: 74% / 26% [--] Total buffers: 12.6G global + 128.9M per thread (400 max threads) [!!] Maximum possible memory usage: 63.0G (404% of installed RAM) [OK] Slow queries: 0% (66/4M) [OK] Highest usage of available connections: 4% (18/400) [OK] Key buffer size / total MyISAM indexes: 256.0M/1.6M [OK] Key buffer hit rate: 98.9% (553K cached / 6K reads) [OK] Query cache efficiency: 67.9% (2M cached / 3M selects) [OK] Query cache prunes per day: 0 [OK] Sorts requiring temporary tables: 0% (16 temp sorts / 86K sorts) [!!] Joins performed without indexes: 4897 [!!] Temporary tables created on disk: 29% (82K on disk / 275K total) [OK] Thread cache hit rate: 99% (18 created / 92K connections) [!!] Table cache hit rate: 0% (2K open / 229K opened) [OK] Open file limit used: 1% (151/9K) [OK] Table locks acquired immediately: 99% (1M immediate / 1M locks) [OK] InnoDB buffer pool / data size: 12.0G/84.8M [OK] InnoDB log waits: 0 -------- Recommendations ----------------------------------------------------- General recommendations: Run OPTIMIZE TABLE to defragment tables for better performance Reduce your overall MySQL memory footprint for system stability Adjust your join queries to always utilize indexes When making adjustments, make tmp_table_size/max_heap_table_size equal Reduce your SELECT DISTINCT queries without LIMIT clauses Increase table_cache gradually to avoid file descriptor limits Read this before increasing table_cache over 64: [url=http://bit.ly/1mi7c4C]table_cache negative scalability - MySQL Performance Blog Variables to adjust: *** MySQL's maximum memory usage is dangerously high *** *** Add RAM before increasing MySQL buffer variables *** join_buffer_size (> 128.0M, or always use indexes with joins) tmp_table_size (> 128M) max_heap_table_size (> 128M) table_cache (> 2000) my.cfn: [mysqld] # InnoDB settings innodb_buffer_pool_size=12G innodb_log_file_size=2G # Binary log/replication log-bin sync_binlog=1 sync_relay_log=1 relay-log-info-repository=TABLE master-info-repository=TABLE expire_logs_days=10 binlog_format=ROW transaction-isolation=READ-COMMITTED innodb_autoinc_lock_mode = 2 # Other #timezone=GMT+1 character-set-server=utf8 collation-server=utf8_general_ci max-connect-errors=100000 max-connections=500 open_files_limit=9708 query_cache_type=1 join_buffer_size=128M tmp_table_size=128M max_heap_table_size=128M query_cache_limit=128M key_buffer = 256M query_cache_size = 256M max_connections = 400 innodb_lock_wait_timeout = 100 I have server with 16GB ram and MySQL 5.6 I am not sure how to set it properly and ask for advice Thanks