ufs_copy fails with aio + compression ― 2009年02月18日 06時03分52秒
Ufs_copy also supports asynchronous I/O which makes coping faster. kldload aio
needs to be done, prior. I verified that it works fine.
Ufs_copy, in addision, takes -c option to create a compressed filesystem image. It uses a copy of cloopfs source code. That is GEOM uzip equivalent. Indeed, it is ufs_copy -c
is equivalent to mkuzip(1) excpet that mkuzip copies every block. ufs_copy is faster and results higher compression rate because how ufs_copy handles unused blocks. This works very well, too.
However, be CAUTIONED. When -a, asynchronous, and -c, compression, are used together, ufs_copy generates unreadable disk image.
$ ufs_copy -a -c -B /dev/da0.journal /usr/local/tmp/da0.uzip
$ mdconfig -a -t vnode -f /usr/local/tmp/da0.uzip
md4
$ mount -r /dev/md4.uzip /mnt/backup/
mount: /dev/md4.uzip : Invalid argument
$ tunefs -p /dev/md4
tunefs: /dev/md4: could not read superblock to fill out disk
$ tunefs -p /dev/md4.uzip
tunefs: /dev/md4.uzip: could not read superblock to fill out disk
$ dumpfs /dev/md4.uzip
dumpfs: /dev/md4.uzip: could not read superblock to fill out disk
最近のコメント