#BEGIN CONFIG INFO #DESCR: 4GB RAM, InnoDB only, ACID, few connections, heavy queries #TYPE: SYSTEM #END CONFIG INFO # # This is a MySQL example config file for systems with 4GB of memory # running mostly MySQL using InnoDB only tables and performing complex # queries with few connections. # # MySQL programs look for option files in a set of # locations which depend on the deployment platform. # You can copy this option file to one of those # locations. For information about these locations, see: # http://dev.mysql.com/doc/mysql/en/option-files.html # # In this file, you can use all long options that a program supports. # If you want to know which options a program supports, run the program # with the "--help" option. # # More detailed information about the individual options can also be # found in the manual. # # # The following options will be read by MySQL client applications. # Note that only client applications shipped by MySQL are guaranteed # to read this section. If you want your own MySQL client program to # honor these values, you need to specify it as an option during the # MySQL client library initialization. # [client] #password = [your_password] port = 3306 socket = /var/lib/mysql/mysql.sock # *** Application-specific options follow here *** # # The MySQL server # [mysqld] # generic configuration options port = 3306 socket = /var/lib/mysql/mysql.sock # back_log is the number of connections the operating system can keep in # the listen queue, before the MySQL connection manager thread has # processed them. If you have a very high connection rate and experience # "connection refused" errors, you might need to increase this value. # Check your OS documentation for the maximum value of this parameter. # Attempting to set back_log higher than your operating system limit # will have no effect. back_log = 50 # Don't listen on a TCP/IP port at all. This can be a security # enhancement, if all processes that need to connect to mysqld run # on the same host. All interaction with mysqld must be made via Unix # sockets or named pipes. # Note that using this option without enabling named pipes on Windows # (via the "enable-named-pipe" option) will render mysqld useless! #skip-networking # The maximum amount of concurrent sessions the MySQL server will # allow. One of these connections will be reserved for a user with # SUPER privileges to allow the administrator to login even if the # connection limit has been reached. max_connections = 100 # Maximum amount of errors allowed per host. If this limit is reached, # the host will be blocked from connecting to the MySQL server until # "FLUSH HOSTS" has been run or the server was restarted. Invalid # passwords and other errors during the connect phase result in # increasing this value. See the "Aborted_connects" status variable for # global counter. max_connect_errors = 10 # The number of open tables for all threads. Increasing this value # increases the number of file descriptors that mysqld requires. # Therefore you have to make sure to set the amount of open files # allowed to at least 4096 in the variable "open-files-limit" in # section [mysqld_safe] table_open_cache = 2048 # Enable external file level locking. Enabled file locking will have a # negative impact on performance, so only use it in case you have # multiple database instances running on the same files (note some # restrictions still apply!) or if you use other software relying on # locking MyISAM tables on file level. #external-locking # The maximum size of a query packet the server can handle as well as # maximum query size server can process (Important when working with # large BLOBs). enlarged dynamically, for each connection. max_allowed_packet = 16M # The size of the cache to hold the SQL statements for the binary log # during a transaction. If you often use big, multi-statement # transactions you can increase this value to get more performance. All # statements from transactions are buffered in the binary log cache and # are being written to the binary log at once after the COMMIT. If the # transaction is larger than this value, temporary file on disk is used # instead. This buffer is allocated per connection on first update # statement in transaction binlog_cache_size = 1M # Maximum allowed size for a single HEAP (in memory) table. This option # is a protection against the accidential creation of a very large HEAP # table which could otherwise use up all memory resources. max_heap_table_size = 64M # Size of the buffer used for doing full table scans. # Allocated per thread, if a full scan is needed. read_buffer_size = 2M # When reading rows in sorted order after a sort, the rows are read # through this buffer to avoid disk seeks. You can improve ORDER BY # performance a lot, if set this to a high value. # Allocated per thread, when needed. read_rnd_buffer_size = 16M # Sort buffer is used to perform sorts for some ORDER BY and GROUP BY # queries. If sorted data does not fit into the sort buffer, a disk # based merge sort is used instead - See the "Sort_merge_passes" # status variable. Allocated per thread if sort is needed. sort_buffer_size = 8M # This buffer is used for the optimization of full JOINs (JOINs without # indexes). Such JOINs are very bad for performance in most cases # anyway, but setting this variable to a large value reduces the # performance impact. See the "Select_full_join" status variable for a # count of full JOINs. Allocated per thread if full join is found join_buffer_size = 8M # How many threads we should keep in a cache for reuse. When a client # disconnects, the client's threads are put in the cache if there aren't # more than thread_cache_size threads from before. This greatly reduces # the amount of thread creations needed if you have a lot of new # connections. (Normally this doesn't give a notable performance # improvement if you have a good thread implementation.) thread_cache_size = 8 # This permits the application to give the threads system a hint for the # desired number of threads that should be run at the same time. This # value only makes sense on systems that support the thread_concurrency() # function call (Sun Solaris, for example). # You should try [number of CPUs]*(2..4) for thread_concurrency thread_concurrency = 8 # Query cache is used to cache SELECT results and later return them # without actual executing the same query once again. Having the query # cache enabled may result in significant speed improvements, if your # have a lot of identical queries and rarely changing tables. See the # "Qcache_lowmem_prunes" status variable to check if the current value # is high enough for your load. # Note: In case your tables change very often or if your queries are # textually different every time, the query cache may result in a # slowdown instead of a performance improvement. query_cache_size = 64M # Only cache result sets that are smaller than this limit. This is to # protect the query cache of a very large result set overwriting all # other query results. query_cache_limit = 2M # Minimum word length to be indexed by the full text search index. # You might wish to decrease it if you need to search for shorter words. # Note that you need to rebuild your FULLTEXT index, after you have # modified this value. ft_min_word_len = 4 # If your system supports the memlock() function call, you might want to # enable this option while running MySQL to keep it locked in memory and # to avoid potential swapping out in case of high memory pressure. Good # for performance. #memlock # Table type which is used by default when creating new tables, if not # specified differently during the CREATE TABLE statement. default-storage-engine = MYISAM # Thread stack size to use. This amount of memory is always reserved at # connection time. MySQL itself usually needs no more than 64K of # memory, while if you use your own stack hungry UDF functions or your # OS requires more stack for some operations, you might need to set this # to a higher value. thread_stack = 192K # Set the default transaction isolation level. Levels available are: # READ-UNCOMMITTED, READ-COMMITTED, REPEATABLE-READ, SERIALIZABLE transaction_isolation = REPEATABLE-READ # Maximum size for internal (in-memory) temporary tables. If a table # grows larger than this value, it is automatically converted to disk # based table This limitation is for a single table. There can be many # of them. tmp_table_size = 64M # Enable binary logging. This is required for acting as a MASTER in a # replication configuration. You also need the binary log if you need # the ability to do point in time recovery from your latest backup. log-bin=mysql-bin # binary logging format - mixed recommended binlog_format=mixed # If you're using replication with chained slaves (A->B->C), you need to # enable this option on server B. It enables logging of updates done by # the slave thread into the slave's binary log. #log_slave_updates # Enable the full query log. Every query (even ones with incorrect # syntax) that the server receives will be logged. This is useful for # debugging, it is usually disabled in production use. #log # Print warnings to the error log file. If you have any problem with # MySQL you should enable logging of warnings and examine the error log # for possible explanations. #log_warnings # Log slow queries. Slow queries are queries which take more than the # amount of time defined in "long_query_time" or which do not use # indexes well, if log_short_format is not enabled. It is normally good idea # to have this turned on if you frequently add new queries to the # system. slow_query_log # All queries taking more than this amount of time (in seconds) will be # trated as slow. Do not use "1" as a value here, as this will result in # even very fast queries being logged from time to time (as MySQL # currently measures time with second accuracy only). long_query_time = 2 # *** Replication related settings # Unique server identification number between 1 and 2^32-1. This value # is required for both master and slave hosts. It defaults to 1 if # "master-host" is not set, but will MySQL will not function as a master # if it is omitted. server-id = 1 # Replication Slave (comment out master section to use this) # # To configure this host as a replication slave, you can choose between # two methods : # # 1) Use the CHANGE MASTER TO command (fully described in our manual) - # the syntax is: # # CHANGE MASTER TO MASTER_HOST=, MASTER_PORT=, # MASTER_USER=, MASTER_PASSWORD= ; # # where you replace , , by quoted strings and # by the master's port number (3306 by default). # # Example: # # CHANGE MASTER TO MASTER_HOST='125.564.12.1', MASTER_PORT=3306, # MASTER_USER='joe', MASTER_PASSWORD='secret'; # # OR # # 2) Set the variables below. However, in case you choose this method, then # start replication for the first time (even unsuccessfully, for example # if you mistyped the password in master-password and the slave fails to # connect), the slave will create a master.info file, and any later # changes in this file to the variable values below will be ignored and # overridden by the content of the master.info file, unless you shutdown # the slave server, delete master.info and restart the slaver server. # For that reason, you may want to leave the lines below untouched # (commented) and instead use CHANGE MASTER TO (see above) # # required unique id between 2 and 2^32 - 1 # (and different from the master) # defaults to 2 if master-host is set # but will not function as a slave if omitted #server-id = 2 # # The replication master for this slave - required #master-host = # # The username the slave will use for authentication when connecting # to the master - required #master-user = # # The password the slave will authenticate with when connecting to # the master - required #master-password = # # The port the master is listening on. # optional - defaults to 3306 #master-port = # Make the slave read-only. Only users with the SUPER privilege and the # replication slave thread will be able to modify data on it. You can # use this to ensure that no applications will accidently modify data on # the slave instead of the master #read_only #*** MyISAM Specific options # Size of the Key Buffer, used to cache index blocks for MyISAM tables. # Do not set it larger than 30% of your available memory, as some memory # is also required by the OS to cache rows. Even if you're not using # MyISAM tables, you should still set it to 8-64M as it will also be # used for internal temporary disk tables. key_buffer_size = 32M # MyISAM uses special tree-like cache to make bulk inserts (that is, # INSERT ... SELECT, INSERT ... VALUES (...), (...), ..., and LOAD DATA # INFILE) faster. This variable limits the size of the cache tree in # bytes per thread. Setting it to 0 will disable this optimisation. Do # not set it larger than "key_buffer_size" for optimal performance. # This buffer is allocated when a bulk insert is detected. bulk_insert_buffer_size = 64M # This buffer is allocated when MySQL needs to rebuild the index in # REPAIR, OPTIMIZE, 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. myisam_sort_buffer_size = 128M # The maximum size of the temporary file MySQL is allowed to use while # recreating the index (during REPAIR, ALTER TABLE or LOAD DATA INFILE. # If the file-size would be bigger than this, the index will be created # through the key cache (which is slower). myisam_max_sort_file_size = 10G # If a table has more than one index, MyISAM can use more than one # thread to repair them by sorting in parallel. This makes sense if you # have multiple CPUs and plenty of memory. myisam_repair_threads = 1 # Automatically check and repair not properly closed MyISAM tables. myisam_recover # *** INNODB Specific options *** # 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 = 16M # 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 = 2G # InnoDB stores data in one or more data files forming the tablespace. # If you have a single logical drive for your data, a single # autoextending file would be good enough. In other cases, a single file # per device is often a good choice. You can configure InnoDB to use raw # disk partitions as well - please refer to the manual for more info # about this. innodb_data_file_path = ibdata1:10M:autoextend # Set this option if you would like the InnoDB tablespace files to be # stored in another location. By default this is the MySQL datadir. #innodb_data_home_dir = # Number of IO threads to use for async IO operations. This value is # hardcoded to 4 on Unix, but on Windows disk I/O may benefit from a # larger number. innodb_file_io_threads = 4 # If you run into InnoDB tablespace corruption, setting this to a nonzero # value will likely help you to dump your tables. Start from value 1 and # increase it until you're able to dump the table successfully. #innodb_force_recovery=1 # 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 = 16 # 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 # Speed up InnoDB shutdown. This will disable InnoDB to do a full purge # and insert buffer merge on shutdown. It may increase shutdown time a # lot, but InnoDB will have to do it on the next startup instead. #innodb_fast_shutdown # 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 # 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 = 256M # Total number of files in the log group. A value of 2-3 is usually good # enough. innodb_log_files_in_group = 3 # Location of the InnoDB log files. Default is the MySQL datadir. You # may wish to point it to a dedicated hard drive or a RAID1 volume for # improved performance #innodb_log_group_home_dir # Maximum allowed percentage of dirty pages in the InnoDB buffer pool. # If it is reached, InnoDB will start flushing them out agressively to # not run out of clean pages at all. This is a soft limit, not # guaranteed to be held. innodb_max_dirty_pages_pct = 90 # The flush method InnoDB will use for Log. The tablespace always uses # doublewrite flush logic. The default value is "fdatasync", another # option is "O_DSYNC". #innodb_flush_method=O_DSYNC # How long an InnoDB transaction should wait for a lock to be granted # before being rolled back. InnoDB automatically detects transaction # deadlocks in its own lock table and rolls back the transaction. If you # use the LOCK TABLES command, or other transaction-safe storage engines # than InnoDB in the same transaction, then a deadlock may arise which # InnoDB cannot notice. In cases like this the timeout is useful to # resolve the situation. innodb_lock_wait_timeout = 120 [mysqldump] # Do not buffer the whole result set in memory before writing it to # file. Required for dumping very large tables quick max_allowed_packet = 16M [mysql] no-auto-rehash # Only allow UPDATEs and DELETEs that use keys. #safe-updates [myisamchk] key_buffer_size = 512M sort_buffer_size = 512M read_buffer = 8M write_buffer = 8M [mysqlhotcopy] interactive-timeout [mysqld_safe] # Increase the amount of open files allowed per process. Warning: Make # sure you have set the global system limit high enough! The high value # is required for a large number of opened tables open-files-limit = 8192