On Fri, 2017-01-20 at 18:24 +0900, Yasunori Goto wrote: : > > > > Like mentioned before, this discussion is more about presentation > > of errors in a known consumable format, rather than recovering from > > errors. While recovering from errors is interesting, we already > > have layers like RAID for that, and they are as applicable to > > NVDIMM backed storage as they have been for disk/SSD based storage. > > I have one question here. > > Certainly, user can use LVM mirroring for storage mode of NVDIMM. > However, NVDIMM has DAX mode. > Can user use LVM mirroring for NVDIMM DAX mode? > I could not find any information that LVM support DAX.... dm-linear and dm-stripe support DAX. This is done by mapping block allocations to LVM physical devices. Once blocks are allocated, all DAX I/Os are direct and do not go through the device-mapper layer. We may be able to change it for read/write paths, but it remains true for mmap. So, I do not think DAX can be supported with LVM mirroring. This does not preclude hardware mirroring, though. -Toshi ��.n��������+%������w��{.n�����{���)��jg��������ݢj����G�������j:+v���w�m������w�������h�����٥