:Could I implement moving the UNDO log by flushing everything to disk, so
:that the UNDO log gets empty and then simply switching the log to the
:new one? IIRC, writing an UNDO entry required the root volume to be
:updated in HAMMER versions <= 3, which is no longer true as of V4.
:
:Regards,
:
: Michael
I think it can be done by acquiring the appropriate lock inside
HAMMER to prevent anyone else from messing with the UNDO area,
then copying the contents to new blocks. Then flush, then
reassign the blocks. The block assignments for the UNDO log are
in the volume header I believe. Then flush the volume header
and you are done.
I haven't looked at it closely but I think that's all there is
to it.
-Matt
Matthew Dillon
<dil...@backplane.com>
