How to speed up a data loading into InnoDB (LOAD D

Question

I want to speed up a data loading.

I use MySQL 5.5, InnoDB and have 1M rows of data (65Mb file). It takes 5 minutes.

What mysql settings and commands affect the speed of LOAD DATA INFILE for InnoDB?

Thank you.

Answer 1

I can recommend these settings to improve load time:

• innodb_doublewrite = 0
• innodb_support_xa = 0
• innodb_buffer_pool_size = (50-80% of system memory)
• innodb_log_file_size = (a large number - 256M etc)
• innodb_flush_log_at_trx_commit = 0

Other than settings, there are some things you can do yourself:

• Create indexes after loading (this is a new optimization with 5.5 / InnoDB plugin).
• Sort the data file before loading.
• Split the data file, and load in parallel.

Answer 2

Try removing indexes and triggers. You can re-create them after the load. Also look into using some of the high-load settings in my-huge.cnf instead of the defaults.

Some more innodb performance settings:

http://www.mysqlperformanceblog.com/2007/11/01/innodb-performance-optimization-basics/

Answer 3

Also make sure that binary logging disabled if possible.

Answer 4

This might not be exactly what you're looking for but is a trick I've used in the past

ALTER TABLE TABLE_NAME DISABLE KEYS;
LOAD DATA INFILE ... ;
ALTER TABLE TABLE_NAME ENABLE KEYS;

Hope it helps.

Answer 5

If you are in a hurry because you are replacing the contents of a live table, then do it this way instead:

CREATE TABLE new LIKE live;
LOAD DATA ... INTO new;
RENAME TABLE live TO old, new TO live;
DROP TABLE old;

The RENAME is 'instantaneous' and atomic, so you are 'never' down, regardless of table size.

(Hence you don't need to worry so much about speeding up the LOAD.)