Mysql is slow with InnoDB during insertion compared to MYISAM

Question

I just installed MySQL 5.5, which has the default InnoDB engine, and the implemented INSERT queries are very slow! After disabling the general journal, it got a little better, but still very slow. I am analyzing mysql to find a problem, but no chance.

Here's a comparative test:

Testing the (n) MYISAM table using 500 rows. - 5866 inserts per second. - 128866 lines per second. - 56306 updates per second.

Testing the INNODB (n) INNODB table using 500 rows. - 9 inserts per second. - 28539 lines per second. - 4358 updates per second.

I have 9 insert queries in InnoDB compared to 5866 with MyISAM.

here is my my.ini (windows 8 64bit):

[mysql] default-character-set=utf8 no-auto-rehash [mysqld] max_allowed_packet = 500M table_open_cache = 512 # The TCP/IP Port the MySQL Server will listen on port=3306 # Path to installation directory. All paths are usually resolved relative to this. basedir="C:\Program Files\MySQL\MySQL Server 5.5\" # Path to the database root datadir="D:\MySQL Datafiles\data\" # The default character set that will be used when a new schema or table is # created and no character set is defined character-set-server=utf8 # The default storage engine that will be used when create new tables when # default-storage-engine=MYISAM # Set the SQL mode to strict sql-mode="STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION" # Enable Windows Authentication # plugin-load=authentication_windows.dll # General and Slow logging. #log-output=FILE #general-log=0 #general_log_file="POOYA.log" #slow-query-log=0 #slow_query_log_file="POOYA-slow.log" #long_query_time=10 #innodb_flush_log_at_trx_commit = 2 # Binary Logging. # log-bin # Error Logging. log-error="POOYA.err" max_connections=100 query_cache_size=32M table_cache=512 tmp_table_size=64M thread_cache_size=8 myisam_max_sort_file_size=100G myisam_sort_buffer_size=64M key_buffer_size=256M # Size of the buffer used for doing full table scans of MyISAM tables. # Allocated per thread, if a full scan is needed. read_buffer_size=1M read_rnd_buffer_size=4M # This buffer is allocated when MySQL needs to rebuild the index in # REPAIR, OPTIMZE, ALTER table statements as well as in LOAD DATA INFILE # into an empty table. It is allocated per thread so be careful with # large settings. sort_buffer_size=1M #*** INNODB Specific options *** # innodb_data_home_dir=0.0 # Use this option if you have a MySQL server with InnoDB support enabled # but you do not plan to use it. This will save memory and disk space # and speed up some things. # skip-innodb # Additional memory pool that is used by InnoDB to store metadata # information. If InnoDB requires more memory for this purpose it will # start to allocate it from the OS. As this is fast enough on most # recent operating systems, you normally do not need to change this # value. SHOW INNODB STATUS will display the current amount used. innodb_additional_mem_pool_size=64M # If set to 1, InnoDB will flush (fsync) the transaction logs to the # disk at each commit, which offers full ACID behavior. If you are # willing to compromise this safety, and you are running small # transactions, you may set this to 0 or 2 to reduce disk I/O to the # logs. Value 0 means that the log is only written to the log file and # the log file flushed to disk approximately once per second. Value 2 # means the log is written to the log file at each commit, but the log # file is only flushed to disk approximately once per second. innodb_flush_log_at_trx_commit=1 # The size of the buffer InnoDB uses for buffering log data. As soon as # it is full, InnoDB will have to flush it to disk. As it is flushed # once per second anyway, it does not make sense to have it very large # (even with long transactions). innodb_log_buffer_size=8M # InnoDB, unlike MyISAM, uses a buffer pool to cache both indexes and # row data. The bigger you set this the less disk I/O is needed to # access data in tables. On a dedicated database server you may set this # parameter up to 80% of the machine physical memory size. Do not set it # too large, though, because competition of the physical memory may # cause paging in the operating system. Note that on 32bit systems you # might be limited to 2-3.5G of user level memory per process, so do not # set it too high. innodb_buffer_pool_size=512M # Size of each log file in a log group. You should set the combined size # of log files to about 25%-100% of your buffer pool size to avoid # unneeded buffer pool flush activity on log file overwrite. However, # note that a larger logfile size will increase the time needed for the # recovery process. innodb_log_file_size=49M # Number of threads allowed inside the InnoDB kernel. The optimal value # depends highly on the application, hardware as well as the OS # scheduler properties. A too high value may lead to thread thrashing. innodb_thread_concurrency=17 [mysqldump] quick max_allowed_packet = 16M [myisamchk] key_buffer_size = 128M sort_buffer_size = 128M read_buffer = 2M write_buffer = 2M [mysqlhotcopy] interactive-timeout 

I edited this file for high performance, also had no problems with mysql 5.1

Answer 1

As required, the commit level in the protocol often causes a lot of disk stress and thereby significantly reduces the data throughput on mysql instances using inno.

Setting mysql.ini to innodb_flush_log_at_trx_commit = 0 (or 2) often solves this problem.

Plese remark, ACID rules would like this value to be 1 ...

Answer 2

Do you add rows one at a time?

If you add multiple rows for each transaction, this helps a lot .

 # 1: INSERT INTO my_table VALUES (1, "A"); INSERT INTO my_table VALUES (2, "B"); # 2: INSERT INTO my_table VALUES (1, "A"),(2, "B"); # 3: BEGIN; INSERT INTO my_table VALUES (1, "A"); INSERT INTO my_table VALUES (2, "B"); COMMIT; 

In InnoDB # 2 and # 3 will be much faster than # 1.

# 2 also helps with MyISAM, but not so much. Rough numbers, I saw that it speeds up MyISAM by 2x and InnoDB by 100x.

Answer 3

You can also install it directly on the MySQL command line using the following command:

 SET GLOBAL innodb_flush_log_at_trx_commit = 0;