>>  MySQLTuner 1.7.13 - 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 passed on the command line
[!!] Currently running unsupported MySQL version 8.0.26-0ubuntu0.20.04.2
[OK] Operating on 64-bit architecture

-------- Log file Recommendations ------------------------------------------------------------------
[--] Log file: /var/log/mysql/error.log(17K)
[OK] Log file /var/log/mysql/error.log exists
[OK] Log file /var/log/mysql/error.log is readable.
[OK] Log file /var/log/mysql/error.log is not empty
[OK] Log file /var/log/mysql/error.log is smaller than 32 Mb
[!!] /var/log/mysql/error.log contains 81 warning(s).
[OK] /var/log/mysql/error.log doesn't contain any error.
[--] 8 start(s) detected in /var/log/mysql/error.log
[--] 1) 2021-08-16T04:45:55.610703Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.26-0ubuntu0.20.04.2'  socket: '/var/run/mysqld/mysqld.sock'  port: 3306  (Ubuntu).
[--] 2) 2021-08-16T04:45:55.610357Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Bind-address: '::' port: 33060, socket: /var/run/mysqld/mysqlx.sock
[--] 3) 2021-08-16T04:39:05.922038Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.26-0ubuntu0.20.04.2'  socket: '/var/run/mysqld/mysqld.sock'  port: 3306  (Ubuntu).
[--] 4) 2021-08-16T04:39:05.921925Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Bind-address: '::' port: 33060, socket: /var/run/mysqld/mysqlx.sock
[--] 5) 2021-08-16T02:41:18.976888Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.26-0ubuntu0.20.04.2'  socket: '/var/run/mysqld/mysqld.sock'  port: 3306  (Ubuntu).
[--] 6) 2021-08-16T02:41:18.976818Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Bind-address: '::' port: 33060, socket: /var/run/mysqld/mysqlx.sock
[--] 7) 2021-08-16T00:02:04.489409Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.26-0ubuntu0.20.04.2'  socket: '/var/run/mysqld/mysqld.sock'  port: 3306  (Ubuntu).
[--] 8) 2021-08-16T00:02:04.489354Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Bind-address: '::' port: 33060, socket: /var/run/mysqld/mysqlx.sock
[--] 3 shutdown(s) detected in /var/log/mysql/error.log
[--] 1) 2021-08-16T04:45:02.862785Z 0 [System] [MY-010910] [Server] /usr/sbin/mysqld: Shutdown complete (mysqld 8.0.26-0ubuntu0.20.04.2)  (Ubuntu).
[--] 2) 2021-08-16T04:39:01.094194Z 0 [System] [MY-010910] [Server] /usr/sbin/mysqld: Shutdown complete (mysqld 8.0.26-0ubuntu0.20.04.2)  (Ubuntu).
[--] 3) 2021-08-16T02:38:29.780742Z 0 [System] [MY-010910] [Server] /usr/sbin/mysqld: Shutdown complete (mysqld 8.0.26-0ubuntu0.20.04.2)  (Ubuntu).

-------- Storage Engine Statistics -----------------------------------------------------------------
[--] Status: +ARCHIVE +BLACKHOLE +CSV -FEDERATED +InnoDB +MEMORY +MRG_MYISAM +MyISAM +PERFORMANCE_SCHEMA
[--] Data in MEMORY tables: 245.0K (Tables: 2)
[--] Data in InnoDB tables: 14.3G (Tables: 434)
[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 --------------------------------------------------------------
[OK] NO SECURITY CVE FOUND FOR YOUR VERSION

-------- Performance Metrics -----------------------------------------------------------------------
[--] Up for: 1h 31m 47s (545K q [99.064 qps], 36K conn, TX: 3G, RX: 79M)
[--] Reads / Writes: 98% / 2%
[--] Binary logging is enabled (GTID MODE: OFF)
[--] Physical Memory     : 3.8G
[--] Max MySQL memory    : 2.4G
[--] Other process memory: 94.4M
[--] Total buffers: 2.0G global + 3.4M per thread (100 max threads)
[--] P_S Max memory usage: 0B
[--] Galera GCache Max memory usage: 0B
[OK] Maximum reached memory usage: 2.3G (59.44% of installed RAM)
[OK] Maximum possible memory usage: 2.4G (61.88% of installed RAM)
[OK] Overall possible memory usage with other process is compatible with memory available
[OK] Slow queries: 0% (62/545K)
[OK] Highest usage of available connections: 72% (72/100)
[OK] Aborted connections: 0.09%  (33/36053)
[--] Query cache have been removed in MySQL 8
[OK] Sorts requiring temporary tables: 0% (60 temp sorts / 86K sorts)
[!!] Joins performed without indexes: 1729
[OK] Temporary tables created on disk: 0% (0 on disk / 15K total)
[OK] Thread cache hit rate: 99% (72 created / 36K connections)
[OK] Table cache hit rate: 96% (3K open / 3K opened)
[OK] Open file limit used: 0% (3/40K)
[OK] Table locks acquired immediately: 98% (2K immediate / 2K locks)
[OK] Binlog cache memory access: 97.45% (6543 Memory / 6714 Total)

-------- Performance schema ------------------------------------------------------------------------
[--] Performance schema is disabled.
[--] Memory used by P_S: 0B
[--] Sys schema is installed.

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

-------- MyISAM Metrics ----------------------------------------------------------------------------
[!!] Key buffer used: 1.4% (117K used / 8M cache)
[!!] Cannot calculate MyISAM index size - re-run script as root user

-------- InnoDB Metrics ----------------------------------------------------------------------------
[--] InnoDB is enabled.
[--] InnoDB Thread Concurrency: 0
[OK] InnoDB File per table is activated
[!!] InnoDB buffer pool / data size: 2.0G/14.3G
[!!] Ratio InnoDB log file size / InnoDB Buffer pool size (11.71875 %): 120.0M * 2/2.0G should be equal 25%
[!!] InnoDB buffer pool instances: 8
[--] Number of InnoDB Buffer Pool Chunk : 16 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: 99.53% (68749176 hits/ 69070802 total)
[!!] InnoDB Write Log efficiency: 86.24% (208872 hits/ 242201 total)
[OK] InnoDB log waits: 0.00% (0 waits / 33329 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
    MySQL was started within the last 24 hours - recommendations may be inaccurate
    Adjust your join queries to always utilize indexes
    Performance schema should be activated for better diagnostics
    Before changing innodb_log_file_size and/or innodb_log_files_in_group read this: https://bit.ly/2TcGgtU
Variables to adjust:
    join_buffer_size (> 1.0M, or always use indexes with JOINs)
    performance_schema = ON enable PFS
    innodb_buffer_pool_size (>= 14.3G) if possible.
    innodb_log_file_size should be (=256M) if possible, so InnoDB total log files size equals to 25% of buffer pool size.
    innodb_buffer_pool_instances(=2)