> On Jul 5, 2018, at 5:23 PM, Ian Jackson <ian.jack...@citrix.com> wrote: > > Sander Eikelenboom writes ("Re: [Xen-devel] [Notes for xen summit 2018 design > session] Process changes: is the 6 monthly release Cadence too short, > Security Process, ..."): >> Thursday, July 5, 2018, 5:14:39 PM, you wrote: >>> So that means that often, and at least from one test flight to the >>> next, all of the base dom0 OS needs to be copied from somewhere else >>> to the test host. This is not currently as fast as it could be, but >>> running d-i is not massively slower than something like FAI. >> >> how about using (LVM) snapshotting (whch does COW) and drop the >> snapshots after a test ? Only do a new OS install once a day/week >> (or point releas) and only after having an OSSTEST pass ? That >> should have fairly little overhead. > > I'm sorry to have to say this, but you seem not to have read what I > wrote above. > > Leaving aside other questions about using LVM for a whole machine > including possible EFI system partition, bootloader etc., where would > the base image be for this LVM snapshot ? > > If it is on the host itself then the previous test can corrupt it. > This is not theoretical: we are doing OS and hypervisor development. > Breakage is to be expected.
What would you think of a “backup partition” scheme instead? I.e., make (say) /dev/sda1 and /dev/sda2 identical size, install to /dev/sda1, use a small “snapshot” netboot utility to dd it into /dev/sda2. Run a test, then dd from /dev/sda2 back into /dev/sda1. If this were only a few gigs it shouldn’t take more than a minute or two. How long does a full install take? In theory of course a wild OS write could corrupt something in an unmounted partition, but in practice the chance of that happening in *our* testing seems seems pretty tiny. (Embedded device manufacturers seem to think this is rare enough to update firmware with, and they have a lot more to lose than we do.) -George _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel