How to optimize the MySQL using scripts

To optimize the mysql, you can use either of the scripts provided below.

The first one is MysqlTuner

The MysqlTuner is a Perl script that analyzes your MySQL performance and, based on the statistics it gathers, gives recommendations which variables you should adjust in order to increase performance. That way, you can tune your my.cnf file to tease out the last bit of performance from your MySQL server and make it work more efficiently.

You can download the MySQLTuner script by

# wget

# chmod 755

Once you make the .pl script executable

# ./

It will show output as below (its sample output)

>> MySQLTuner 1.0.0 – Major Hayden

>> Bug reports, feature requests, and downloads at

>> Run with ‘–help’ for additional options and output filtering

——– General Statistics ————————————————–

[–] Skipped version check for MySQLTuner script

[OK] Currently running supported MySQL version 5.0.81-community

[!!] Switch to 64-bit OS – MySQL cannot currently use all of your RAM

——– Storage Engine Statistics ——————————————-

[–] Status: +Archive -BDB -Federated +InnoDB -ISAM -NDBCluster

[–] Data in MyISAM tables: 374M (Tables: 3987)

[–] Data in InnoDB tables: 3M (Tables: 98)

[–] Data in MEMORY tables: 0B (Tables: 2)

[!!] Total fragmented tables: 201

——– Performance Metrics ————————————————-

[–] Up for: 14d 0h 24m 52s (12M q [10.043 qps], 491K conn, TX: 3B, RX: 1B)

[–] Reads / Writes: 86% / 14%

[–] Total buffers: 442.0M global + 12.3M per thread (100 max threads)

[OK] Maximum possible memory usage: 1.6G (41% of installed RAM)

[OK] Slow queries: 0% (91/12M)

[!!] Highest connection usage: 100% (101/100)

[OK] Key buffer size / total MyISAM indexes: 384.0M/111.0M

[OK] Key buffer hit rate: 100.0% (3B cached / 1M reads)

[OK] Query cache efficiency: 75.8% (7M cached / 9M selects)

[!!] Query cache prunes per day: 33741

[OK] Sorts requiring temporary tables: 0% (1 temp sorts / 1M sorts)

[!!] Joins performed without indexes: 53627

[!!] Temporary tables created on disk: 35% (587K on disk / 1M total)

[OK] Thread cache hit rate: 99% (2K created / 491K connections)

[!!] Table cache hit rate: 1% (512 open / 38K opened)

[OK] Open file limit used: 24% (1K/4K)

[OK] Table locks acquired immediately: 99% (3M immediate / 3M locks)

[OK] InnoDB data size / buffer pool: 3.7M/8.0M

——– Recommendations —————————————————–

General recommendations:

Run OPTIMIZE TABLE to defragment tables for better performance

Enable the slow query log to troubleshoot bad queries

Reduce or eliminate persistent connections to reduce connection usage

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

Variables to adjust:

max_connections (> 100)

wait_timeout (< 28800)

interactive_timeout (< 28800) query_cache_size (> 32M)

join_buffer_size (> 128.0K, or always use indexes with joins)

tmp_table_size (> 32M)

max_heap_table_size (> 16M)

table_cache (> 512)

Check the “Recommendations” and edit the my.cnf accordingly.

You can use another script as below.

Its MySQL Performance Tuning Primer Script which can be downloadd from

# wget

# chmod 755

# ./

It will provide sample output as below.


– By: Matthew Montgomery –

MySQL Version 5.0.81-community i686

Uptime = 30 days 0 hrs 20 min 55 sec

Avg. qps = 10

Total Questions = 12160398

Threads Connected = 3

Server has been running for over 65hrs.

It should be safe to follow these recommendations

To find out more information on how each of these

runtime variables effects performance visit:


for info about MySQL’s Enterprise Monitoring and Advisory Service


The slow query log is NOT enabled.

Current long_query_time = 10 sec.

You have 90 out of 12160419 that take longer than 10 sec. to complete

Your long_query_time may be too high, I typically set this under 5 sec.


The binary update log is NOT enabled.

You will not be able to do point in time recovery



Current thread_cache_size = 8

Current threads_cached = 5

Current threads_per_sec = 0

Historic threads_per_sec = 0

Your thread_cache_size is fine


Current max_connections = 100

Current threads_connected = 3

Historic max_used_connections = 101

The number of used connections is 101% of the configured maximum.

You should raise max_connections


Max Memory Ever Allocated : 1.63 G

Configured Max Per-thread Buffers : 1.20 G

Configured Max Global Buffers : 426 M

Configured Max Memory Limit : 1.61 G

Physical Memory : 3.96 G

Max memory limit seem to be within acceptable norms


Current MyISAM index space = 108 M

Current key_buffer_size = 384 M

Key cache miss rate is 1 : 3157

Key buffer free ratio = 85 %

Your key_buffer_size seems to be fine


Query cache is enabled

Current query_cache_size = 32 M

Current query_cache_used = 18 M

Current query_cache_limit = 1 M

Current Query cache Memory fill ratio = 59.10 %

Current query_cache_min_res_unit = 4 K

MySQL won’t cache query results that are larger than query_cache_limit in size


Current sort_buffer_size = 2 M

Current read_rnd_buffer_size = 8 M

Sort buffer seems to be fine


Current join_buffer_size = 132.00 K

You have had 53627 queries where a join could not use an index properly

You should enable “log-queries-not-using-indexes”

Then look for non indexed joins in the slow query log.

If you are unable to optimize your queries you may want to increase your

join_buffer_size to accommodate larger joins in one pass.

Note! This script will still suggest raising the join_buffer_size when

ANY joins not using indexes are found.


Current open_files_limit = 4096 files

The open_files_limit should typically be set to at least 2x-3x

that of table_cache if you have heavy MyISAM usage.

Your open_files_limit value seems to be fine


Current table_cache value = 512 tables

You have a total of 4104 tables

You have 512 open tables.

Current table_cache hit rate is 1%, while 100% of your table cache is in use

You should probably increase your table_cache


Current max_heap_table_size = 16 M

Current tmp_table_size = 32 M

Of 1081722 temp tables, 35% were created on disk

Effective in-memory tmp_table_size is limited to max_heap_table_size.

Perhaps you should increase your tmp_table_size and/or max_heap_table_size

to reduce the number of disk-based temporary tables

Note! BLOB and TEXT columns are not allow in memory tables.

If you are using these columns raising these values might not impact your

ratio of on disk temp tables.


Current read_buffer_size = 2 M

Current table scan ratio = 1537 : 1

read_buffer_size seems to be fine


Current Lock Wait ratio = 1 : 1545

You may benefit from selective use of InnoDB.

If you have long running SELECT’s against MyISAM tables and perform

frequent updates consider setting ‘low_priority_updates=1′

If you have a high concurrency of inserts.

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