MySQL – Server Zustand und Optimierung mittels Performance Tuning Primer Script

Eine Möglichkeit eine umfassende Analyse über den Zustand der Konfiguration und der Leistung des laufenden MySQL Servers zu erhalten ist das Performance Tuning Primer Script von Matthew Montgomery. Nachfolgend werde ich die kurze Einrichtung und ein Beispiel einer Auswertung unter Debian zeigen.

Installation

# wget http://www.day32.com/MySQL/tuning-primer.sh && chmod +x tuning-primer.sh

Ausführen

Am Anfang versucht das Script den Zugang / Login zum Server selber aufzulösen. Sollte hier z.B. noch keine vorkonfigurierte my.cnf im Homeverzeichnis liegen, werden die Zugangsdaten für den Administrator des MySQL Servers abgefragt und angeboten eine solche Datei zu erstellen. Danach folgen dann die ausführlichen Auswertungen und die Empfehlungen für die Optimierung der Datenbanken im Anschluss.

# ./tuning-primer.sh

Using login values from ~/.my.cnf
– INITIAL LOGIN ATTEMPT FAILED –
Testing for stored webmin passwords:
None Found
Could not auto detect login info!
Found potential sockets: /var/run/mysqld/mysqld.sock
Using: /var/run/mysqld/mysqld.sock
Would you like to provide a different socket?: [y/N] n
Do you have your login handy ? [y/N] : y
User: xxx
Password: xxx

Would you like me to create a ~/.my.cnf file for you? [y/N] : n

— MYSQL PERFORMANCE TUNING PRIMER —
– By: Matthew Montgomery –

MySQL Version 5.1.73-1 x86_64

Uptime = 57 days 13 hrs 2 min 55 sec
Avg. qps = 26
Total Questions = 130081415
Threads Connected = 3

Server has been running for over 48hrs.
It should be safe to follow these recommendations

To find out more information on how each of these
runtime variables effects performance visit:
http://dev.mysql.com/doc/refman/5.1/en/server-system-variables.html
Visit http://www.mysql.com/products/enterprise/advisors.html
for info about MySQL’s Enterprise Monitoring and Advisory Service

SLOW QUERIES
The slow query log is NOT enabled.
Current long_query_time = 10.000000 sec.
You have 253 out of 130081436 that take longer than 10.000000 sec. to complete
Your long_query_time seems to be fine

BINARY UPDATE LOG
The binary update log is NOT enabled.
You will not be able to do point in time recovery
See http://dev.mysql.com/doc/refman/5.1/en/point-in-time-recovery.html

WORKER THREADS
Current thread_cache_size = 8
Current threads_cached = 7
Current threads_per_sec = 0
Historic threads_per_sec = 0
Your thread_cache_size is fine

MAX CONNECTIONS
Current max_connections = 151
Current threads_connected = 3
Historic max_used_connections = 46
The number of used connections is 30% of the configured maximum.
Your max_connections variable seems to be fine.

INNODB STATUS
Current InnoDB index space = 7 M
Current InnoDB data space = 21 M
Current InnoDB buffer pool free = 0 %
Current innodb_buffer_pool_size = 8 M
Depending on how much space your innodb indexes take up it may be safe
to increase this value to up to 2 / 3 of total system memory

MEMORY USAGE
Max Memory Ever Allocated : 165 M
Configured Max Per-thread Buffers : 405 M
Configured Max Global Buffers : 42 M
Configured Max Memory Limit : 447 M
Physical Memory : 5.35 G
Max memory limit seem to be within acceptable norms

KEY BUFFER
Current MyISAM index space = 88 M
Current key_buffer_size = 16 M
Key cache miss rate is 1 : 262
Key buffer free ratio = 81 %
Your key_buffer_size seems to be fine

QUERY CACHE
Query cache is enabled
Current query_cache_size = 16 M
Current query_cache_used = 11 M
Current query_cache_limit = 1 M
Current Query cache Memory fill ratio = 70.56 %
Current query_cache_min_res_unit = 4 K
MySQL won’t cache query results that are larger than query_cache_limit in size

SORT OPERATIONS
Current sort_buffer_size = 2 M
Current read_rnd_buffer_size = 256 K
Sort buffer seems to be fine

JOINS
Current join_buffer_size = 132.00 K
You have had 1169617 queries where a join could not use an index properly
You have had 6248 joins without keys that check for key usage after each row
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.

OPEN FILES LIMIT
Current open_files_limit = 1024 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

TABLE CACHE
Current table_open_cache = 64 tables
Current table_definition_cache = 256 tables
You have a total of 971 tables
You have 64 open tables.
Current table_cache hit rate is 0%
, while 100% of your table cache is in use
You should probably increase your table_cache
You should probably increase your table_definition_cache value.

TEMP TABLES
Current max_heap_table_size = 16 M
Current tmp_table_size = 16 M
Of 7224815 temp tables, 23% were created on disk
Created disk tmp tables ratio seems fine

TABLE SCANS
Current read_buffer_size = 128 K
Current table scan ratio = 140 : 1
read_buffer_size seems to be fine

TABLE LOCKING
Current Lock Wait ratio = 1 : 114
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 on Dynamic row-length tables
consider setting ‚concurrent_insert=2‘.

So weit so gut. Aufpassen sollte man bei dem Punkt „Table Cache“ und hier ggf. den Link zu dem Artikel lesen, bevor man einfach den Wert nach oben schiebt. Eine weitere Möglichkeit ist das MySQL-Tuner Perl Script