Re: [RFC 2/8] Aufs2: structure

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

 



> The struct of a xino file is simple, just a sequence of aufs inode
> numbers which is indexed by the lower inode number.
> In the above sample, assume the inode number of /ro/fileA is i111 and
> aufs assigns the inode number i999 for fileA. Then aufs writes 999 as
> 4(8) bytes at 111 * 4(8) bytes offset in the xino file.

I think it is worth mentioning that the xino file, if I understand it correctly, is a 'sparse file', that means it is full of 'holes' and doesn't consume as much disk space as it might appear.

In my opinion, the current xino-file approach is not much usable on filesystems which do not support sparse files (for example, if you wish to union two vfats), since some 'seeks' would probably write a lot of nulls. But I am not any kernel developer so I don't even know if there exists any filesystem which would be unable to support sparse files (except the mentioned VFAT, of course).


Tomas M
slax.org

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

[Index of Archives]     [Linux Ext4 Filesystem]     [Union Filesystem]     [Filesystem Testing]     [Ceph Users]     [Ecryptfs]     [AutoFS]     [Kernel Newbies]     [Share Photos]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux Cachefs]     [Reiser Filesystem]     [Linux RAID]     [Samba]     [Device Mapper]     [CEPH Development]
  Powered by Linux