On Tue, Aug 7, 2012 at 2:44 PM, Benoît Canet <benoit.ca...@gmail.com> wrote: > This patchset create a block driver implementing a quorum using three qemu > disk > images. Writes are mirrored on the three files. > For the reading part the three files are read at the same time and a vote is > done to determine which is the majority qiov version. It then return this > majority version to the upper layers. > When three differents versions of the data are returned by the lower layer the > quorum is broken and the read return -EIO.
If you make the quorum setting configurable, then this can replace blkverify. n=2 is blkverify, n=3 is your current patch series, n/m is also possible where n=number of mirrors and m=threshold needed to achieve quorum. Stefan
