Re: [PATCH 05/12] fs: add a F_IOINFO fcntl

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, Feb 28, 2017 at 08:51:39AM -0800, Darrick J. Wong wrote:
> Hm... is fio_alignment is specified in units of bytes?

Yes.

> If so, then
> shouldn't this be a __u32 so that we can handle some weird future device
> that wants, say, 1MB alignment for its atomic IO?

That would be pretty useless.  Anything bigger than sector / block
size would not really be usable for typical applications.

> Though, now that I look at the XFS ioinfo patch, I guess fio_alignment
> is set only for O_DIRECT files?

Yes.

> So it's really the required alignment
> for directio operations.

For buffered I/O we can write at byte granularity and still use the
atomic commits, but for direct I/O we can only COW at block size
granularity.
--
To unsubscribe from this list: send the line "unsubscribe linux-xfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [XFS Filesystem Development (older mail)]     [Linux Filesystem Development]     [Linux Audio Users]     [Yosemite Trails]     [Linux Kernel]     [Linux RAID]     [Linux SCSI]


  Powered by Linux