On Thu, Jul 30, 2015 at 5:26 PM, derek <denc716@xxxxxxxxx> wrote: > On Thu, Jul 30, 2015 at 11:24 AM, Chris Murphy <lists@xxxxxxxxxxxxxxxxx> wrote: >> Could be this: >> https://bugzilla.redhat.com/show_bug.cgi?id=1220950 >> >> However I don't see the same snapshot message in that bug, that you get. >> > > No, it's different. > > This bug is as easy to reproduce: run Fedora 22 Live Mode on laptop or VM, > it boots default into liveuser, try a `sudo dnf install 'Development > Tools'` then kernel crash, > from console I collected the dm-0 IO Errors. Yes it's reproducible. The problem is not inherently with device-mapper. It's a configuration issue where the snapshot is too small and it's a fixed size, doesn't grow. So it fills up, the file system face plants, then kernel oopses. The untested workaround for this for baremetal install is to re-create the installer media using livecd-iso-to-disk with the --overlay-size-mb option and set to something like 1000. Now there will be a live overlay of sufficient size for this installation. For VM, just install the OS and then install the tools post-install. > This is always reproducible that makes me think Fedora Live Mode is > not usable at all, or maybe no users at all. Your snark amuses me. I might try to recruit you for QA. > On Thu, Jul 30, 2015 at 11:28 AM, Chris Murphy <lists@xxxxxxxxxxxxxxxxx> wrote: >> >> Also, overlayfs is really recently added to the kernel. It's much much >> newer than device mapper stuff. So I wouldn't call it immature. You >> might be thinking of the thin provisioning snapshots which is much >> newer, but still has been around longer than overlayfs. But I don't >> think the live media is using thin snapshots (?) I think they're the >> conventional (thick) type. > > The fact is with overlayfs (or aufs from 2014 Ubuntu release) Live > Linux you can apt-get install whatever (write to /) as much data as > possible; till it becomes full and returns -ENOSPACE (and continues > usable if clean some data), on this Fedora Live OS with device-mapper > and simple sudo dnf install a few packages crashes kernel. Which is > more mature? Feel free to ask a kernel developer. Based on development time and testing, device-mapper has a lot more of both compared to overlayfs. On that basis alone I think device-mapper is more mature by a lot. The failure of your use case with Fedora is a configuration related issue rather than device-mapper vs overlayfs. Whether your use case should be better supported I don't know, so I asked on the devel@ list. And in the footnote are the technical details on why this fails. https://lists.fedoraproject.org/pipermail/devel/2015-July/212956.html -- Chris Murphy -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
