MySQL my.cnf tweak for faster importing large database

Few small hack will ease you importing large sized mysql dump in a bit faster process. The trick worked for me for a 70 GB dumped sql, can’t guarantee it’d work for you!


need to change the following:

innodb_buffer_pool_size = 4G
innodb_log_buffer_size = 256M
innodb_log_file_size = 1G
innodb_write_io_threads = 16
innodb_flush_log_at_trx_commit = 0

Why these settings ?

innodb_buffer_pool_size will cache frequently read data
innodb_log_buffer_size : Larger buffer reduces write I/O to Transaction Logs
innodb_log_file_size : Larger log file reduces checkpointing and write I/O
innodb_write_io_threads : Service Write Operations to .ibd files. According to MySQL Documentation on Configuring the Number of Background InnoDB I/O Threads, each thread can handle up to 256 pending I/O requests. Default for MySQL is 4, 8 for Percona Server. Max is 64.
innodb_flush_log_at_trx_commitIn the event of a crash, both 0 and 2 can lose once second of data.
The tradeoff is that both 0 and 2 increase write performance.
I choose 0 over 2 because 0 flushes the InnoDB Log Buffer to the Transaction Logs (ib_logfile0, ib_logfile1) once per second, with or without a commit. Setting 2 flushes the InnoDB Log Buffer only on commit. There are other advantages to setting 0 mentioned by @jynus, a former Percona instructor.

Restart mysql like this

service mysql restart --innodb-doublewrite=0

This disables the InnoDB Double Write Buffer. Import your data. When done, restart mysql normally. This re-enables the InnoDB Double Write Buffer.

service mysql restart


Add these 2 lines-

service mysql restart

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