Direct IO and Page cache

[Valdis.Kletnieks at vt.edu]

On Thu, 25 Jul 2013 23:15:49 -0400, Kumar amit mehta said:

> applications are being written. So one bad day somebody comes up with
> an application which does both these two types of IO(one that goes
> through page cache and the other that doesn't) and in that application,
> one instance is writing directly to the backend device and the other
> instance, who is not aware of this write, goes ahead and writes to the
> page cache, and that write would be written later to the backend device.
> So wouldn't we end up corrupting the on disk data.

Applications that intermix O_DIRECT and non-O_DIRECT to the same file
get what they deserve.  Consider it evolution in action, you're not going
to get any sympathy from the kernel community for this.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 865 bytes
Desc: not available
Url : http://lists.kernelnewbies.org/pipermail/kernelnewbies/attachments/20130726/78e61101/attachment-0001.bin