Re: DragonFly-2.3.1.868.g90eca master sbin/hammer cmd_expand.c sys/vfs/hammer hammer_expand.c hammer_ioctl.h

[Michael Neumann <mneumann@xxxxxxxx>]

Matthew Dillon schrieb:
> :It works online!
> :
> :Just ignore the last two lines of the example.  What I wanted to show
> :is that after the expansion you have to specify both devices to
> :mount_hammer, otherwise it will not work.
> :
> :I hope I can get the freemap formatting in today, so that
> :the space of the volume can be used in the filesystem.
> :
> :Regards,
> :
> :   Michael
>
>     Very cool.  Now we need a command to migrate data off a volume and
>     then remove the volume!

Yeah! But lets make expansion stable first. I think replacing the root
volume can be quite tricky, as one has to move the layer1 array and has
to take care that the undo log is correctly "moved" to another volume.
Btw, is there a pointer to the undo log (i.e. can it be placed on
any volume) or is the undo log implicitly assumed to be on the
root-volume?

When I expand a hammer filesystem, upon umount I still get the following
message:

  HAMMER: umount flushing......... giving up

Right now, I split the layer1/layer2 formatting into two steps.
At first I format layer2 (using bread/bwrite), then after the call to
hammer_install_volume() I do all the layer1 formatting using
hammer_bread (for current hard disks this is just one entry) etc.

Do you think it makes sense to do all the formatting using hammer_xxx
functions? I think it is easier to not split the layer1/layer2
formatting into two steps.

Regards,

  Michael