how to use O_DIRECT ?

Stephan_Craft · 10-04-2009, 12:36 PM

Hi,
yesterday i moved from MYISAM to innodb and everything works great, than i changed innodb_flush_method to O_DIRECT and things work even better...

my question is, what O_DIRECT do? how to use it with apache httpd or other services?

zhjim · 10-05-2009, 05:16 AM

http://dev.mysql.com/doc/refman/5.1/...b_flush_method for further reading

O_DIRECT is just the way things are getting synced to disk. InnoDB uses memory in every fashion, but somehow the data has to be stored permanently on the disk. That the syncing mechanism.
As far as I recall there is no similar option to apache. Mainly cause it only writes logs...