>>  MySQLTuner 1.7.19 - 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] Currently running supported MySQL version 8.0.17
    [OK] Operating on 64-bit architecture

    -------- Log file Recommendations ------------------------------------------------------------------
    [OK] Log file /var/log/mysql/error.log exists
    [--] Log file: /var/log/mysql/error.log(873K)
    [OK] Log file /var/log/mysql/error.log is readable.
    [OK] Log file /var/log/mysql/error.log is empty
    [OK] Log file /var/log/mysql/error.log is smaller than 32 Mb
    -------- Storage Engine Statistics -----------------------------------------------------------------
    [--] Status: +ARCHIVE +BLACKHOLE +CSV -FEDERATED +InnoDB +MEMORY +MRG_MYISAM +MyISAM +PERFORMANCE_SCHEMA
    [--] Data in InnoDB tables: 241.7G (Tables: 464101)
    [--] Data in MyISAM tables: 4.0K (Tables: 4)
    [--] Data in MEMORY tables: 0B (Tables: 37)
    [OK] Total fragmented tables: 0

    -------- Analysis Performance Metrics --------------------------------------------------------------
    [--] innodb_stats_on_metadata: OFF
    [OK] No stat updates during querying INFORMATION_SCHEMA.

    -------- Security Recommendations ------------------------------------------------------------------
    [--] Skipped due to unsupported feature for MySQL 8

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

    -------- Performance Metrics -----------------------------------------------------------------------
    [--] Up for: 7m 34s (102 q [0.225 qps], 99 conn, TX: 69K, RX: 20K)
    [--] Reads / Writes: 100% / 0%
    [--] Binary logging is enabled (GTID MODE: ON)
    [--] Physical Memory     : 47.2G
    [--] Max MySQL memory    : 337.2G
    [--] Other process memory: 0B
    [--] Total buffers: 24.4G global + 104.2M per thread (3072 max threads)
    [--] P_S Max memory usage: 72B
    [--] Galera GCache Max memory usage: 0B
    [OK] Maximum reached memory usage: 24.8G (52.68% of installed RAM)
    [!!] Maximum possible memory usage: 337.2G (714.91% of installed RAM)
    [!!] Overall possible memory usage with other process exceeded memory
    [OK] Slow queries: 0% (0/102)
    [OK] Highest usage of available connections: 0% (4/3072)
    [OK] Aborted connections: 1.01%  (1/99)
    [!!] name resolution is active : a reverse name resolution is made for each new connection and can reduce performance
    [--] Query cache have been removed in MySQL 8
    [OK] No Sort requiring temporary tables
    [OK] No joins without indexes
    [OK] Temporary tables created on disk: 0% (0 on disk / 4 total)
    [OK] Thread cache hit rate: 97% (2 created / 99 connections)
    [OK] Table cache hit rate: 54% (97 open / 179 opened)
    [!!] table_definition_cache(2000) is lower than number of tables(464470)
    [OK] Open file limit used: 0% (8/10K)
    [OK] Table locks acquired immediately: 100% (4 immediate / 4 locks)
    [OK] Binlog cache memory access: 100.00% (3 Memory / 3 Total)

    -------- Performance schema ------------------------------------------------------------------------
    [--] Memory used by P_S: 72B
    [--] Sys schema is installed.

    -------- ThreadPool Metrics ------------------------------------------------------------------------
    [--] ThreadPool stat is disabled.

    -------- MyISAM Metrics ----------------------------------------------------------------------------
    [--] MyISAM Metrics are disabled on last MySQL versions.

    -------- InnoDB Metrics ----------------------------------------------------------------------------
    [--] InnoDB is enabled.
    [--] InnoDB Thread Concurrency: 12
    [OK] InnoDB File per table is activated
    [!!] InnoDB buffer pool / data size: 24.0G/241.7G
    [!!] Ratio InnoDB log file size / InnoDB Buffer pool size (2.08333333333333 %): 256.0M * 2/24.0G should be equal to 25%
    [!!] InnoDB buffer pool instances: 8
    [--] Number of InnoDB Buffer Pool Chunk : 192 for 8 Buffer Pool Instance(s)
    [OK] Innodb_buffer_pool_size aligned with Innodb_buffer_pool_chunk_size & Innodb_buffer_pool_instances
    [OK] InnoDB Read buffer efficiency: 99.84% (1933866 hits/ 1936895 total)
    [OK] InnoDB Write log efficiency: 90.45% (1137 hits/ 1257 total)
    [OK] InnoDB log waits: 0.00% (0 waits / 120 writes)

    -------- AriaDB Metrics ----------------------------------------------------------------------------
    [--] AriaDB is disabled.

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

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

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

    -------- Replication Metrics -----------------------------------------------------------------------
    [--] Galera Synchronous replication: NO
    [--] No replication slave(s) for this server.
    [--] Binlog format: ROW
    [--] XA support enabled: ON
    [--] Semi synchronous replication Master: Not Activated
    [--] Semi synchronous replication Slave: Not Activated
    [--] This is a standalone server

    -------- Recommendations ---------------------------------------------------------------------------
    General recommendations:
        Control warning line(s) into /var/log/mysql/error.log file
        Control error line(s) into /var/log/mysql/error.log file
        MySQL was started within the 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
        Before changing innodb_log_file_size and/or innodb_log_files_in_group read this: https://bit.ly/2TcGgtU
    Variables to adjust:
      *** MySQL's maximum memory usage is dangerously high ***
      *** Add RAM before increasing MySQL buffer variables ***
        table_definition_cache(2000) > 464470 or -1 (autosizing if supported)
        innodb_buffer_pool_size (>= 241.7G) if possible.
        innodb_log_file_size should be (=3G) if possible, so InnoDB total log files size equals to 25% of buffer pool size.
        innodb_buffer_pool_instances(=24)