Re: [Fwd: Re: Linking two files together][RFC]

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

 



On Wed, 9 Jun 2010, Roberto Ragusa wrote:
> I hope that ideas about btrfs are not off-topic for this mailing list.
> 
> The forwarded message below was written by me on fedora-users.
> The thread is about the ability to link two files in a manner
> similar to "cat 1 2 >3 && rm 1 2" while avoiding any data
> movement on the disk.
> The implementation should just put the original extents together in
> the new file. Is there any filesystem which is capable of doing that?
> As btrfs is already based on extents and COW, couldn't this feature be
> evaluated for feasibility? I think a lot of usages will be found
> for it if actually implemented.

Btrfs already has a CLONE_RANGE ioctl that will clone a range of 
(block-aligned) bytes from file A to any offset in file B.  The fs just 
fixes up the file metadata to reference the same bytes on disk without 
reading or writing any actual file data.

sage
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Filesystem Development]     [Linux NFS]     [Linux NILFS]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux