Re: Stale NFS file handle when using aufs on top of btrfs?

[Michael Johnson - MJ]

   I'll try to get to this today/tonight.

   I see another difference between my test case and yours which might be
   altering the result.  In my case, both branches are on physically separate
   file systems rather than directories on the same fs.  I'll check and see if
   this makes a difference in the result for me.

   On Feb 2, 2015 8:56 PM, <[1]sf...@users.sourceforge.net> wrote:

     Michael Johnson - MJ:
     > I think I know why you were unable to recreate the problem.  It appears
     to
     > only occur in attempt the test case from a directory contained within
     the
     > aufs mount point, and not the base of the mount itself.  In fact, if
     the
     > directory you are in exists in all branches, the problem does not
     occur.  I
     > have verified that this problem does not occur when the underlying
     > filesystes are all ext4, but it does occur when they are all btrfs.
     Hmm...
     Still I cannot reproduce the problem.
     Linux jrofr 3.13.11.6aufsD #8 SMP Mon Feb 2 13:56:32 JST 2015 x86_64
     x86_64 x86_64 GNU/Linux
     /dev/sda15 / btrfs rw,relatime,space_cache 0 0
     + sudo mount -t aufs -o br=/rw:/ro=rw none /u
     [Â  Â 51.057477] aufs 3.13-20140303
     + sudo mkdir -p /u/dir1/dir2/dir3
     + cd /u/dir1
     + sudo rm -fr dir2
     + ls
     (no error)
     > I can try building a new aufs module, but I will need some directions to
     > get that started.
     - get all source files of ubuntu trusty and build as it is
     Â  $ git clone git://[2]kernel.ubuntu.com/ubuntu/ubuntu-trusty.git
     Â  $ cd ubuntu-trusty
     Â  $ fakeroot make-kpkg --uc --us --config silentoldconfig configure
     Â  $ fakeroot make-kpkg --uc --us --append_to_version -aufsD --revision
     `date +%y%m%d%H%M` kernel_image
     Â  (lots of time and space are necessary)
     - install the built kernel pkg
     Â  $ dpkg -i ../linux-image-....deb
     - reboot
     - make sure you can receive "kern.debug" logs
     Â  $ logger -p kern.debug testing
     Â  check the kernel log
     - reproduce the problem, in order to make sure
     Â  check the kernel log
     - enable debugging
     Â  $ cd ubuntu-trusty
     Â  $ make menuconfig
     Â  Â  enable CONFIG_AUFS_DEBUG
     Â  Â  (menu) "Ubuntu Supplied Third-Party Device Drivers"
     Â  Â  Â  Â  Â  Â --> "Aufs (Advanced multi layered unification filesystem)
     support"
     Â  Â  Â  Â  Â  Â  Â  Â --> "Debug aufs"
     - re-run "make-kpkg ... kernel_image" and re-install the pkg
     - reboot
     - reproduce the problem
     Â  check the kernel log
     - apply the patch in
     Â
     [3]http://www.mail-archive.com/aufs-users@lists.sourceforge.net/msg04991.h
     tml
     - re-run "make-kpkg ... kernel_image" and re-install the pkg
     - reboot
     - reproduce the problem
     Â  check the kernel log
     > If it would be helpful, I can figure out have to give you ssh access to
     > this VM if you want to provide me with an SSH public to add.
     Can I reboot the system and check the log anytime via ssh?
     If so, I will send my public key privately.
     J. R. Okajima

References

   1. mailto:sf...@users.sourceforge.net
   2. http://kernel.ubuntu.com/ubuntu/ubuntu-trusty.git
   3. http://www.mail-archive.com/aufs-users@lists.sourceforge.net/msg04991.html

------------------------------------------------------------------------------
Dive into the World of Parallel Programming. The Go Parallel Website,
sponsored by Intel and developed in partnership with Slashdot Media, is your
hub for all things parallel software development, from weekly thought
leadership blogs to news, videos, case studies, tutorials and more. Take a
look and join the conversation now. http://goparallel.sourceforge.net/