One reason to use O_DIRECT
One reason to use O_DIRECT
Posted Aug 25, 2010 16:33 UTC (Wed) by bhaskar (guest, #69531)Parent article: The 2010 Linux Storage and Filesystem Summit, day 2
The journal (log) file of a database is a write-only file under normal operation. It needs to be read from only during recovery. Using O_DIRECT with a decent IO subsystem means that more the file buffer cache is available for the database file itself, where it helps since databases are read and written.