mySQLtuner.pl result

 >>  MySQLTuner 1.7.1 - Major Hayden <major@mhtx.net>
 >>  Bug reports, feature requests, and downloads at http://mysqltuner.com/
 >>  Run with '--help' for additional options and output filtering

[--] Skipped version check for MySQLTuner script
[OK] Logged in using credentials from debian maintenance account.
[OK] Currently running supported MySQL version 10.1.22-MariaDB-1~jessie
[OK] Operating on 64-bit architecture

-------- Log file Recommendations ------------------------------------------------------------------
[--] Log file: (0B)
[!!] Log file  doesn't exist
[!!] Log file  isn't readable.

-------- Storage Engine Statistics -----------------------------------------------------------------
[--] Status: +Aria +CSV +InnoDB +MEMORY +MRG_MyISAM +MyISAM +PERFORMANCE_SCHEMA +SEQUENCE
[--] Data in InnoDB tables: 259M (Tables: 28)
[OK] Total fragmented tables: 0

-------- Security Recommendations ------------------------------------------------------------------
[OK] There are no anonymous accounts for any database users
[OK] All database users have passwords assigned
[!!] There is no basic password file list!

-------- CVE Security Recommendations --------------------------------------------------------------
[--] Skipped due to --cvefile option undefined

-------- Performance Metrics -----------------------------------------------------------------------
[--] Up for: 14s (405 q [28.929 qps], 12 conn, TX: 785K, RX: 67K)
[--] Reads / Writes: 95% / 5%
[--] Binary logging is enabled (GTID MODE: OFF)
[--] Physical Memory     : 494.4M
[--] Max MySQL memory    : 1.0G
[--] Other process memory: 228.6M
[--] Total buffers: 658.0M global + 7.5M per thread (50 max threads)
[--] P_S Max memory usage: 0B
[--] Galera GCache Max memory usage: 0B
[!!] Maximum reached memory usage: 673.1M (136.13% of installed RAM)
[!!] Maximum possible memory usage: 1.0G (209.25% of installed RAM)
[!!] Overall possible memory usage with other process exceeded memory
[OK] Slow queries: 0% (0/405)
[OK] Highest usage of available connections: 4% (2/50)
[OK] Aborted connections: 0.00%  (0/12)
[!!] name resolution is active : a reverse name resolution is made for each new connection and can reduce performance
[!!] Query cache may be disabled by default due to mutex contention.
[!!] Query cache efficiency: 19.3% (87 cached / 450 selects)
[OK] Query cache prunes per day: 0
[OK] Sorts requiring temporary tables: 0% (0 temp sorts / 52 sorts)
[!!] Joins performed without indexes: 2
[!!] Temporary tables created on disk: 76% (38 on disk / 50 total)
[OK] Thread cache hit rate: 83% (2 created / 12 connections)
[OK] Table cache hit rate: 81% (27 open / 33 opened)
[OK] Open file limit used: 0% (26/16K)
[OK] Table locks acquired immediately: 100% (410 immediate / 410 locks)
[OK] Binlog cache memory access: 100.00% (16 Memory / 16 Total)

-------- Performance schema ------------------------------------------------------------------------
[--] Performance schema is disabled.
[--] Memory used by P_S: 0B
[--] Sys schema isn't installed.

-------- ThreadPool Metrics ------------------------------------------------------------------------
[--] ThreadPool stat is enabled.
[--] Thread Pool Size: 1 thread(s).
[--] Using default value is good enough for your version (10.1.22-MariaDB-1~jessie)

-------- MyISAM Metrics ----------------------------------------------------------------------------
[!!] Key buffer used: 18.2% (24M used / 134M cache)
[OK] Key buffer size / total MyISAM indexes: 128.0M/123.0K

-------- InnoDB Metrics ----------------------------------------------------------------------------
[--] InnoDB is enabled.
[--] InnoDB Thread Concurrency: 0
[OK] InnoDB File per table is activated
[!!] InnoDB buffer pool / data size: 256.0M/259.8M
[!!] Ratio InnoDB log file size / InnoDB Buffer pool size (37.5 %): 48.0M * 2/256.0M should be equal 25%
[!!] InnoDB buffer pool <= 1G and Innodb_buffer_pool_instances(!=1).
[--] InnoDB Buffer Pool Chunk Size not used or defined in your version
[OK] InnoDB Read buffer efficiency: 99.37% (162357 hits/ 163393 total)
[!!] InnoDB Write Log efficiency: 72.86% (51 hits/ 70 total)
[OK] InnoDB log waits: 0.00% (0 waits / 19 writes)

-------- AriaDB Metrics ----------------------------------------------------------------------------
[--] AriaDB is enabled.
[OK] Aria pagecache size / total Aria indexes: 128.0M/1B
[OK] Aria pagecache hit rate: 97.0% (730 cached / 22 reads)

-------- TokuDB Metrics ----------------------------------------------------------------------------
[--] TokuDB is disabled.

-------- XtraDB Metrics ----------------------------------------------------------------------------
[--] XtraDB is disabled.

-------- RocksDB Metrics ---------------------------------------------------------------------------
[--] RocksDB is disabled.

-------- Spider Metrics ----------------------------------------------------------------------------
[--] Spider is disabled.

-------- Connect Metrics ---------------------------------------------------------------------------
[--] Connect is disabled.

-------- Galera Metrics ----------------------------------------------------------------------------
[--] Galera is disabled.

-------- Replication Metrics -----------------------------------------------------------------------
[--] Galera Synchronous replication: NO
[--] No replication slave(s) for this server.
[--] This is a standalone server.

-------- Recommendations ---------------------------------------------------------------------------
General recommendations:
    MySQL started within last 24 hours - recommendations may be inaccurate
    Reduce your overall MySQL memory footprint for system stability
    Dedicate this server to your database for highest performance.
    Configure your accounts with ip or subnets only, then update your configuration with skip-name-resolve=1
    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 which have no LIMIT clause
    Performance should be activated for better diagnostics
    Consider installing Sys schema from https://github.com/mysql/mysql-sys
Variables to adjust:
  *** MySQL's maximum memory usage is dangerously high ***
  *** Add RAM before increasing MySQL buffer variables ***
    query_cache_size (=0)
    query_cache_type (=0)
    query_cache_limit (> 128K, or use smaller result sets)
    join_buffer_size (> 256.0K, or always use indexes with joins)
    tmp_table_size (> 64M)
    max_heap_table_size (> 64M)
    performance_schema = ON enable PFS
    innodb_buffer_pool_size (>= 259M) if possible.
    innodb_log_file_size * innodb_log_files_in_group should be equals to 1/4 of buffer pool size (=128M) if possible.
    innodb_buffer_pool_instances (=1)