Suggestion About MySQL (5.7) Optimization
Posted by: Jack UK
Date: February 01, 2020 12:50PM

Hi everyone,

Firstly, I'm new here. If the topic is not in right category for this.

I have a cloud machine on AWS. The machine has 2 GB RAM, 1 vCPU, 50 GB SSD.

An open-source, e-commerce script runs on it with PHP 7.3 and MySQL 5.7.

MySQL has arround 300 tables (InnoDB), 2 GB.

I installed MySQL Tunner, is working for 4-5 days.

I'll share the output. Would you comment to them please?

There is no code block in this editor. :/
>> MySQLTuner 1.7.19 - Major Hayden <>
[OK] Currently running supported MySQL version 5.7.26
[OK] Operating on 64-bit architecture

[OK] Log file /opt/bitnami/mysql/data/mysqld.log exists
[--] Log file: /opt/bitnami/mysql/data/mysqld.log(187K)
[OK] Log file /opt/bitnami/mysql/data/mysqld.log is readable.
[OK] Log file /opt/bitnami/mysql/data/mysqld.log is not empty
[OK] Log file /opt/bitnami/mysql/data/mysqld.log is smaller than 32 Mb
[!!] /opt/bitnami/mysql/data/mysqld.log contains 78 warning(s).
[!!] /opt/bitnami/mysql/data/mysqld.log contains 40 error(s).
[--] 25 start(s) detected in /opt/bitnami/mysql/data/mysqld.log
[--] 1) 2020-01-29T10:01:46.722081Z 0 [Note] /opt/bitnami/mysql/bin/mysqld.bin: ready for connections.
[--] 10) 2020-01-29T08:30:51.403160Z 0 [Note] /opt/bitnami/mysql/bin/mysqld.bin: ready for connections.
[--] 21 shutdown(s) detected in /opt/bitnami/mysql/data/mysqld.log
[--] 1) 2020-01-29T10:01:42.837601Z 0 [Note] /opt/bitnami/mysql/bin/mysqld.bin: Shutdown complete
[--] 10) 2020-01-29T08:11:48.085422Z 0 [Note] /opt/bitnami/mysql/bin/mysqld.bin: Shutdown complete

-------- Storage Engine Statistics -----------------------------------------------------------------
[--] Data in InnoDB tables: 1.3G (Tables: 302)
[--] Data in MyISAM tables: 35.5K (Tables: 6)
[OK] Total fragmented tables: 0

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

-------- Security Recommendations ------------------------------------------------------------------
[OK] There are no anonymous accounts for any database users
[OK] All database users have passwords assigned
[!!] User 'DB_BDLUSR@%' does not specify hostname restrictions.
[!!] There is no basic password file list!

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

-------- Performance Metrics -----------------------------------------------------------------------
[--] Up for: 3d 7h 39m 27s (80M q [279.115 qps], 147K conn, TX: 81G, RX: 20G)
[--] Reads / Writes: 98% / 2%
[--] Binary logging is disabled
[--] Physical Memory : 2.0G
[--] Max MySQL memory : 6.0G
[--] Other process memory: 0B
[--] Total buffers: 234.0M global + 39.2M per thread (151 max threads)
[--] P_S Max memory usage: 0B
[--] Galera GCache Max memory usage: 0B
[OK] Maximum reached memory usage: 1.3G (66.70% of installed RAM)
[!!] Maximum possible memory usage: 6.0G (308.25% of installed RAM)
[!!] Overall possible memory usage with other process exceeded memory
[OK] Slow queries: 0% (0/80M)
[OK] Highest usage of available connections: 18% (28/151)
[OK] Aborted connections: 0.00% (2/147769)
[!!] Query cache may be disabled by default due to mutex contention.
[OK] Query cache efficiency: 72.8% (57M cached / 79M selects)
[!!] Query cache prunes per day: 5506703
[OK] Sorts requiring temporary tables: 0% (8K temp sorts / 4M sorts)
[!!] Joins performed without indexes: 57369
[OK] Temporary tables created on disk: 8% (476K on disk / 5M total)
[OK] Thread cache hit rate: 99% (28 created / 147K connections)
[!!] Table cache hit rate: 2% (2K open / 71K opened)
[OK] table_definition_cache(1000) is upper than number of tables(587)
[OK] Open file limit used: 0% (20/5K)
[OK] Table locks acquired immediately: 100% (3K immediate / 3K locks)

-------- 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: 18.3% (1M used / 8M cache)
[OK] Key buffer size / total MyISAM indexes: 8.0M/55.0K
[OK] Read Key buffer hit rate: 96.8% (2K cached / 78 reads)

-------- InnoDB Metrics ----------------------------------------------------------------------------
[--] InnoDB is enabled.
[--] InnoDB Thread Concurrency: 0
[OK] InnoDB File per table is activated
[!!] InnoDB buffer pool / data size: 128.0M/1.3G
[!!] Ratio InnoDB log file size / InnoDB Buffer pool size (75 %): 48.0M * 2/128.0M should be equal to 25%
[OK] InnoDB buffer pool instances: 1
[--] Number of InnoDB Buffer Pool Chunk : 1 for 1 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: 99.80% (1992943853 hits/ 1996852014 total)
[!!] InnoDB Write Log efficiency: 82.08% (2113892 hits/ 2575548 total)
[OK] InnoDB log waits: 0.00% (0 waits / 461656 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 /opt/bitnami/mysql/data/mysqld.log file
Control error line(s) into /opt/bitnami/mysql/data/mysqld.log file
Restrict Host for 'DB_USR'@% to DB_USR@SpecificDNSorIp
UPDATE mysql.user SET host ='SpecificDNSorIp' WHERE user='DB_USR' AND host ='%'; FLUSH PRIVILEGES;
Reduce your overall MySQL memory footprint for system stability
Dedicate this server to your database for highest performance.
We will suggest raising the 'join_buffer_size' until JOINs not using indexes are found.
(specially the conclusions at the bottom of the page).
Increase table_open_cache gradually to avoid file descriptor limits
Read this before increasing table_open_cache over 64:
Read this before increasing for MariaDB
This is MyISAM only table_cache scalability problem, InnoDB not affected.
See more details here:
This bug already fixed in MySQL 5.7.9 and newer MySQL versions.
Beware that open_files_limit (5000) variable
should be greater than table_open_cache (2100)
Performance schema should be activated for better diagnostics
Before changing innodb_log_file_size and/or innodb_log_files_in_group read this:

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_size (> 50M)
join_buffer_size (> 2.0M, or always use indexes with JOINs)
table_open_cache (> 2100)
performance_schema = ON enable PFS
innodb_buffer_pool_size (>= 1.3G) if possible.
innodb_log_file_size should be (=16M) if possible, so InnoDB total log files size equals to 25% of buffer pool size.


Many thanks!

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Suggestion About MySQL (5.7) Optimization
February 01, 2020 12:50PM

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