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Full Discussion: Is Concurrent I/O (CIO) available on Linux?
Operating Systems Linux Is Concurrent I/O (CIO) available on Linux? Post 302405451 by jim mcnamara on Friday 19th of March 2010 12:10:52 AM
Old 03-19-2010
No, there is nothing that exactly matches concurrent I/O. AFAIK. You can back into it by turning off file caching, for example:

You can drop_caches for a one-time flush:

Writing to this will cause the kernel to drop clean caches, dentries and
inodes from memory, causing that memory to become free.
Code:
To free pagecache:
	echo 1 > /proc/sys/vm/drop_caches
To free dentries and inodes:
	echo 2 > /proc/sys/vm/drop_caches
To free pagecache, dentries and inodes:
	echo 3 > /proc/sys/vm/drop_caches

This is a non-destructive operation and dirty data objects are not freeable, the
user should run `sync' first.

You can mount filesystems
Code:
 mount -o sync ....

to bypass file caching
The dirsync flag also bypasses file metadata update caching. Doing these can increase your exposure to possible data loss for long term operation.

You can use the O_DIRECT flag on open.

If this question refers to a db applications I would bet the system designers are aware of all of this for a linux install. Are you experiencing performance issues?
 

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RHNPLUGIN(8)							   Red Hat, Inc.						      RHNPLUGIN(8)

NAME

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DESCRIPTION

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SEE ALSO

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