Trying out `shiftfs`

What’s shiftfs

shiftfs is a kernel filesystem which was initially developed by James Bottomley, then stabilized and extended by @sforshee and @brauner.
That filesystem acts like an overlay on top of an existing mount on the host and then allows mounting inside the container, shifting uid/gid on all filesystem operations. This allows for instant creation and startup of unprivileged containers as no costly filesystem remapping is needed on creation or startup.

In tests, on fast systems backed by NVME storage, we’ve seen the typical lxc launch time for an Ubuntu 18.04 image go from around 2.5s down to just 500ms. For systems using hard disks, the difference should be far more noticeable, possibly saving tens of seconds.

shiftfs will also allow for multiple containers that use non-overlapping maps (security.idmap.isolated=true) to share custom storage volumes, which is currently impossible.

Where can it be found

At this time, shiftfs isn’t mainline. It’s included in the Ubuntu kernel starting with 5.0 and some other Linux distributions may pick it up. It should also be reasonably easy to package as a DKMS package for distributions that ship a suitably recent kernel.

Ubuntu users have it in their kernel out of the box, this can be confirmed with modinfo shiftfs.
As we had to fix a few early issues, you should make sure that your kernel is fully up to date and you are booted onto it.

Limitations

The only limitation we’re currently aware of is that shiftfs will prevent the use of overlayfs inside the container. This may break Docker users. If this applies to you, you should stay away from shiftfs for now.

How can it be used

The easiest is with the LXD snap on version 3.12 or higher. We currently have it disabled out of the box because of the above limitations but you can opt into it if those don’t apply to you.

To turn it on, do:

  • sudo snap set lxd shiftfs.enable=true
  • sudo systemctl reload snap.lxd.daemon

You can then run:

  • lxc info

And should see:

    shiftfs: "true"

Under the kernel_features header. If you see it, then you’ve got it enabled.

After that, any newly created container will use shiftfs.
To convert an existing container, the easiest is to temporarily convert it to privileged:

  • lxc config set NAME security.privileged true
  • lxc restart NAME
  • lxc config unset NAME security.privileged
  • lxc restart NAME

Feedback

Any feedback on shiftfs would be appreciated and we will be updating the limitations section above as we become aware of new issues.

Once all of them are addressed, we will slowly start rolling it out by default to our users as this is a significant performance improvement and completely avoids the rather complex and risky remapping logic that we have to use today.

6 Likes

I looked at it for my 18.04 LTS and all I found is a PPA. It’s not exactly ‘out of the box’ IMO. According to this there may be some hope for August 2019.

Linux 5.0 is currently available in Ubuntu 19.04 or newer. Indeed, it will reach the latest LTS at Ubuntu 18.04.3 (1st Aug).

2 Likes

Here are some benchmarks, on Ubuntu 19.10 (latest daily).

Before enabling shiftfs

myusername@myusername-desktop:~$ time lxc launch ubuntu:18.04 mycontainer
Creating mycontainer
Starting mycontainer

real	0m2,551s
user	0m0,074s
sys	0m0,033s
myusername@myusername-desktop:~$ time lxc launch ubuntu:18.04 mycontainer2
Creating mycontainer2
Starting mycontainer2

real	0m2,550s
user	0m0,071s
sys	0m0,034s
myusername@myusername-desktop:~$ time lxc launch ubuntu:18.04 mycontainer3
Creating mycontainer3
Starting mycontainer3

real	0m2,718s
user	0m0,069s
sys	0m0,036s
myusername@myusername-desktop:~$ 

After enabling shiftfs

myusername@myusername-desktop:~$ time lxc launch ubuntu:18.04 mycontainer
Creating mycontainer
Starting mycontainer

real	0m0,513s
user	0m0,070s
sys	0m0,041s
myusername@myusername-desktop:~$ time lxc launch ubuntu:18.04 mycontainer2
Creating mycontainer2
Starting mycontainer2

real	0m0,473s
user	0m0,066s
sys	0m0,031s
myusername@myusername-desktop:~$ time lxc launch ubuntu:18.04 mycontainer3
Creating mycontainer3
Starting mycontainer3

real	0m0,550s
user	0m0,072s
sys	0m0,027s
myusername@myusername-desktop:~$ 

This shows that the creation speed went from 2.5s down to 500s (SSD disk, using ZFS over a loop file).

Using lxd-benchmark but no shiftfs

$ lxd.benchmark launch --count 10 --parallel 10 ubuntu:18.04
Test environment:
  Server backend: lxd
  Server version: 3.14
  Kernel: Linux
  Kernel architecture: x86_64
  Kernel version: 5.0.0-17-generic
  Storage backend: zfs
  Storage version: 0.7.12-1ubuntu5
  Container backend: lxc
  Container version: 3.1.0

Test variables:
  Container count: 10
  Container mode: unprivileged
  Startup mode: normal startup
  Image: ubuntu:18.04
  Batches: 1
  Batch size: 10
  Remainder: 0

[Jul  2 12:41:37.107] Found image in local store: 6ae1c6e92017402f1aee655fa8d785ee9d2337a3369d76115cecad5e7a303e07
[Jul  2 12:41:37.107] Batch processing start
[Jul  2 12:41:46.664] Processed 10 containers in 9.557s (1.046/s)
[Jul  2 12:41:46.664] Batch processing completed in 9.557s

Using lxd-benchmark and shiftfs

$ lxd.benchmark launch --count 10 --parallel 10 ubuntu:18.04
Test environment:
  Server backend: lxd
  Server version: 3.14
  Kernel: Linux
  Kernel architecture: x86_64
  Kernel version: 5.0.0-17-generic
  Storage backend: zfs
  Storage version: 0.7.12-1ubuntu5
  Container backend: lxc
  Container version: 3.1.0

Test variables:
  Container count: 10
  Container mode: unprivileged
  Startup mode: normal startup
  Image: ubuntu:18.04
  Batches: 1
  Batch size: 10
  Remainder: 0

[Jul  2 12:38:16.553] Found image in local store: 6ae1c6e92017402f1aee655fa8d785ee9d2337a3369d76115cecad5e7a303e07
[Jul  2 12:38:16.553] Batch processing start
[Jul  2 12:38:18.353] Processed 10 containers in 1.800s (5.557/s)
[Jul  2 12:38:18.353] Batch processing completed in 1.800s

This was launching 10 Ubuntu containers in parallel. The time spent, when from 9.5s way down to 1.8s.

2 Likes

The 5.0 kernel is available for Ubuntu 18.04 users as linux-generic-hwe-18.04-edge.

That edge kernel will then get promoted to just linux-generic-hwe-18.04 with the next point release of Ubuntu 18.04.

After the Bionic 5.0 HWE kernel was released I recreated my Disco container to use shiftfs. After running fine for several days, this morning I found that processes running as part of a manual apt update (like gpgv) were hanging in D state. I was able to kill them with ^C. Stopping the container took a long time as well. This is with LXD 3.15 (11437).

So I deleted the container and created it without shiftfs and will watch for the problem to recur. I had no problems running this Disco container with the previous Bionic 4.18 HWE kernel. I use a “real” ZFS for container storage and a “real” bridge with its own network interface. The only unusual part of the configuration is that the container is on a WireGuard VPN using the kernel module from the host.

Can you show uname -a and the output of dmesg?

Normally such hangs are indicative of a kernel issue and should be accompanied by a kernel trace in dmesg.

Linux kif 5.0.0-23-generic #24~18.04.1-Ubuntu SMP Mon Jul 29 16:12:28 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

The dmesg -T output below starts from when I first logged in after first booting into 5.0. After enabling shiftfs as specified earlier in this thread, I deleted and relaunched the container disco and it ran fine for several days. df -T inside the container confirmed that shiftfs was in use.

Based on reviewing journalctl messages, here’s what I think I did (all times local):

Jul 31 19:12:14: First boot into HWE 5.0.0
Jul 31 19:12:31: Login; container disco remains stopped from before reboot
Jul 31 19:14:31: Ran lxc list; lxd starts
Jul 31 19:16:53: Enable shiftfs; delete and launch container disco
Jul 31 19:32:49: Container disco starts with shiftfs (after new image downloads)
Jul 31 19:33:10: Run scripts to configure container and set up WireGuard
Aug 04 07:??:??: Processes in container disco hang during apt update
Aug 04 07:44:02: Stop container disco; this took longer than usual
Aug 04 07:52:58: Delete container disco
Aug 04 07:53:05: Disable shiftfs and launch container disco

[Wed Jul 31 19:14:32 2019] new mount options do not match the existing superblock, will be ignored
[Wed Jul 31 19:16:52 2019] kauditd_printk_skb: 32 callbacks suppressed
[Wed Jul 31 19:16:52 2019] audit: type=1400 audit(1564615013.130:44): apparmor="DENIED" operation="open" profile="snap.lxd.hook.configure" name="/var/lib/snapd/hostfs/usr/lib/os-release" pid=2190 comm="snap-exec" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
[Wed Jul 31 19:16:53 2019] audit: type=1400 audit(1564615013.390:45): apparmor="DENIED" operation="open" profile="snap.lxd.hook.configure" name="/var/lib/snapd/hostfs/usr/lib/os-release" pid=2211 comm="snapctl" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
[Wed Jul 31 19:16:53 2019] audit: type=1400 audit(1564615013.454:46): apparmor="DENIED" operation="open" profile="snap.lxd.hook.configure" name="/var/lib/snapd/hostfs/usr/lib/os-release" pid=2219 comm="snapctl" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
[Wed Jul 31 19:16:53 2019] audit: type=1400 audit(1564615013.462:47): apparmor="DENIED" operation="open" profile="snap.lxd.hook.configure" name="/var/lib/snapd/hostfs/usr/lib/os-release" pid=2225 comm="snapctl" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
[Wed Jul 31 19:16:53 2019] audit: type=1400 audit(1564615013.474:48): apparmor="DENIED" operation="open" profile="snap.lxd.hook.configure" name="/var/lib/snapd/hostfs/usr/lib/os-release" pid=2234 comm="snapctl" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
[Wed Jul 31 19:16:53 2019] audit: type=1400 audit(1564615013.482:49): apparmor="DENIED" operation="open" profile="snap.lxd.hook.configure" name="/var/lib/snapd/hostfs/usr/lib/os-release" pid=2243 comm="snapctl" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
[Wed Jul 31 19:16:53 2019] audit: type=1400 audit(1564615013.494:50): apparmor="DENIED" operation="open" profile="snap.lxd.hook.configure" name="/var/lib/snapd/hostfs/usr/lib/os-release" pid=2253 comm="snapctl" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
[Wed Jul 31 19:32:49 2019] audit: type=1400 audit(1564615969.722:51): apparmor="STATUS" operation="profile_load" profile="unconfined" name="lxd-disco_</var/snap/lxd/common/lxd>" pid=10556 comm="apparmor_parser"
[Wed Jul 31 19:32:49 2019] br0: port 2(veth31XCZZ) entered blocking state
[Wed Jul 31 19:32:49 2019] br0: port 2(veth31XCZZ) entered disabled state
[Wed Jul 31 19:32:49 2019] device veth31XCZZ entered promiscuous mode
[Wed Jul 31 19:32:49 2019] br0: port 2(veth31XCZZ) entered blocking state
[Wed Jul 31 19:32:49 2019] br0: port 2(veth31XCZZ) entered forwarding state
[Wed Jul 31 19:32:49 2019] br0: port 2(veth31XCZZ) entered disabled state
[Wed Jul 31 19:32:49 2019] eth0: renamed from vethEAGWGM
[Wed Jul 31 19:32:49 2019] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
[Wed Jul 31 19:32:49 2019] IPv6: ADDRCONF(NETDEV_CHANGE): veth31XCZZ: link becomes ready
[Wed Jul 31 19:32:49 2019] br0: port 2(veth31XCZZ) entered blocking state
[Wed Jul 31 19:32:49 2019] br0: port 2(veth31XCZZ) entered forwarding state
[Wed Jul 31 19:32:49 2019] new mount options do not match the existing superblock, will be ignored
[Wed Jul 31 19:32:50 2019] audit: type=1400 audit(1564615970.754:52): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="nvidia_modprobe" pid=10840 comm="apparmor_parser"
[Wed Jul 31 19:32:50 2019] audit: type=1400 audit(1564615970.754:53): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="nvidia_modprobe//kmod" pid=10840 comm="apparmor_parser"
[Wed Jul 31 19:32:50 2019] audit: type=1400 audit(1564615970.882:54): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/usr/sbin/tcpdump" pid=10841 comm="apparmor_parser"
[Wed Jul 31 19:32:50 2019] audit: type=1400 audit(1564615970.954:55): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/usr/bin/man" pid=10842 comm="apparmor_parser"
[Wed Jul 31 19:32:50 2019] audit: type=1400 audit(1564615970.954:56): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="man_filter" pid=10842 comm="apparmor_parser"
[Wed Jul 31 19:32:50 2019] audit: type=1400 audit(1564615970.954:57): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="man_groff" pid=10842 comm="apparmor_parser"
[Wed Jul 31 19:32:50 2019] audit: type=1400 audit(1564615971.082:58): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/sbin/dhclient" pid=10837 comm="apparmor_parser"
[Wed Jul 31 19:32:50 2019] audit: type=1400 audit(1564615971.086:59): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/usr/lib/NetworkManager/nm-dhcp-client.action" pid=10837 comm="apparmor_parser"
[Wed Jul 31 19:32:50 2019] audit: type=1400 audit(1564615971.086:60): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/usr/lib/NetworkManager/nm-dhcp-helper" pid=10837 comm="apparmor_parser"
[Wed Jul 31 19:33:07 2019] kauditd_printk_skb: 3 callbacks suppressed
[Wed Jul 31 19:33:07 2019] audit: type=1400 audit(1564615987.503:64): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/snap/core/7270/usr/lib/snapd/snap-confine" pid=11724 comm="apparmor_parser"
[Wed Jul 31 19:33:07 2019] audit: type=1400 audit(1564615987.503:65): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/snap/core/7270/usr/lib/snapd/snap-confine//mount-namespace-capture-helper" pid=11724 comm="apparmor_parser"
[Wed Jul 31 19:33:07 2019] audit: type=1400 audit(1564615987.543:66): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap-update-ns.core" pid=11727 comm="apparmor_parser"
[Wed Jul 31 19:33:07 2019] audit: type=1400 audit(1564615987.671:67): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.core.hook.configure" pid=11728 comm="apparmor_parser"
[Wed Jul 31 19:33:10 2019] audit: type=1400 audit(1564615990.971:68): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/snap/core/7270/usr/lib/snapd/snap-confine" pid=11801 comm="apparmor_parser"
[Wed Jul 31 19:33:10 2019] audit: type=1400 audit(1564615990.975:69): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/snap/core/7270/usr/lib/snapd/snap-confine//mount-namespace-capture-helper" pid=11801 comm="apparmor_parser"
[Wed Jul 31 19:33:10 2019] audit: type=1400 audit(1564615991.003:70): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap-update-ns.core" pid=11946 comm="apparmor_parser"
[Wed Jul 31 19:33:10 2019] audit: type=1400 audit(1564615991.143:71): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.core.hook.configure" pid=11947 comm="apparmor_parser"
[Wed Jul 31 19:33:10 2019] PKCS#7 signature not signed with a trusted key
[Wed Jul 31 19:33:10 2019] wireguard: module verification failed: signature and/or required key missing - tainting kernel
[Wed Jul 31 19:33:10 2019] wireguard: WireGuard 0.0.20190702 loaded. See www.wireguard.com for information.
[Wed Jul 31 19:33:10 2019] wireguard: Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
[Wed Jul 31 19:33:14 2019] audit: type=1400 audit(1564615994.899:72): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap-update-ns.lxd" pid=12516 comm="apparmor_parser"
[Wed Jul 31 19:33:14 2019] audit: type=1400 audit(1564615995.059:73): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.benchmark" pid=12518 comm="apparmor_parser"
[Wed Jul 31 19:33:14 2019] audit: type=1400 audit(1564615995.091:74): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.buginfo" pid=12519 comm="apparmor_parser"
[Wed Jul 31 19:33:14 2019] audit: type=1400 audit(1564615995.099:75): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.check-kernel" pid=12520 comm="apparmor_parser"
[Wed Jul 31 19:33:14 2019] audit: type=1400 audit(1564615995.099:76): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.activate" pid=12517 comm="apparmor_parser"
[Wed Jul 31 19:33:14 2019] audit: type=1400 audit(1564615995.239:77): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.daemon" pid=12521 comm="apparmor_parser"
[Wed Jul 31 19:33:14 2019] audit: type=1400 audit(1564615995.271:78): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.hook.configure" pid=12522 comm="apparmor_parser"
[Wed Jul 31 19:33:14 2019] audit: type=1400 audit(1564615995.279:79): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.hook.install" pid=12523 comm="apparmor_parser"
[Wed Jul 31 19:33:14 2019] audit: type=1400 audit(1564615995.279:80): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.lxc" pid=12524 comm="apparmor_parser"
[Wed Jul 31 19:33:15 2019] audit: type=1400 audit(1564615995.391:81): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.lxd" pid=12525 comm="apparmor_parser"
[Wed Jul 31 19:33:19 2019] kauditd_printk_skb: 34 callbacks suppressed
[Wed Jul 31 19:33:19 2019] audit: type=1400 audit(1564615999.911:116): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.core.hook.configure" pid=12736 comm="apparmor_parser"
[Wed Jul 31 19:33:19 2019] audit: type=1400 audit(1564616000.295:117): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.activate" pid=12786 comm="apparmor_parser"
[Wed Jul 31 19:33:19 2019] audit: type=1400 audit(1564616000.299:118): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.check-kernel" pid=12789 comm="apparmor_parser"
[Wed Jul 31 19:33:19 2019] audit: type=1400 audit(1564616000.299:119): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.buginfo" pid=12788 comm="apparmor_parser"
[Wed Jul 31 19:33:19 2019] audit: type=1400 audit(1564616000.299:120): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.benchmark" pid=12787 comm="apparmor_parser"
[Wed Jul 31 19:33:20 2019] audit: type=1400 audit(1564616000.471:121): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.hook.install" pid=12792 comm="apparmor_parser"
[Wed Jul 31 19:33:20 2019] audit: type=1400 audit(1564616000.479:122): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.hook.configure" pid=12791 comm="apparmor_parser"
[Wed Jul 31 19:33:20 2019] audit: type=1400 audit(1564616000.499:123): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.lxc" pid=12793 comm="apparmor_parser"
[Wed Jul 31 19:33:20 2019] audit: type=1400 audit(1564616000.575:124): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.daemon" pid=12790 comm="apparmor_parser"
[Wed Jul 31 19:33:20 2019] audit: type=1400 audit(1564616000.655:125): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.lxd" pid=12794 comm="apparmor_parser"
[Wed Jul 31 19:33:25 2019] kauditd_printk_skb: 20 callbacks suppressed
[Wed Jul 31 19:33:25 2019] audit: type=1400 audit(1564616005.575:146): apparmor="DENIED" operation="file_inherit" namespace="root//lxd-disco_<var-snap-lxd-common-lxd>" profile="/snap/core/7270/usr/lib/snapd/snap-confine" pid=13002 comm="snap-confine" family="netlink" sock_type="raw" protocol=15 requested_mask="send receive" denied_mask="send receive"
[Wed Jul 31 19:33:25 2019] audit: type=1400 audit(1564616005.587:147): apparmor="DENIED" operation="file_inherit" namespace="root//lxd-disco_<var-snap-lxd-common-lxd>" profile="snap.lxd.hook.configure" name="/apparmor/.null" pid=13002 comm="snap-exec" requested_mask="wr" denied_mask="wr" fsuid=1000000 ouid=0
[Wed Jul 31 19:34:18 2019] audit: type=1400 audit(1564616059.211:148): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="nvidia_modprobe" pid=13885 comm="apparmor_parser"
[Wed Jul 31 19:34:18 2019] audit: type=1400 audit(1564616059.211:149): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="nvidia_modprobe//kmod" pid=13885 comm="apparmor_parser"
[Wed Jul 31 19:34:19 2019] audit: type=1400 audit(1564616059.859:150): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="nvidia_modprobe" pid=13940 comm="apparmor_parser"
[Wed Jul 31 19:34:19 2019] audit: type=1400 audit(1564616059.887:151): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="nvidia_modprobe//kmod" pid=13940 comm="apparmor_parser"
[Wed Jul 31 19:34:19 2019] audit: type=1400 audit(1564616059.979:152): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/usr/bin/man" pid=13942 comm="apparmor_parser"
[Wed Jul 31 19:34:19 2019] audit: type=1400 audit(1564616059.979:153): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="man_filter" pid=13942 comm="apparmor_parser"
[Wed Jul 31 19:34:19 2019] audit: type=1400 audit(1564616059.979:154): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="man_groff" pid=13942 comm="apparmor_parser"
[Wed Jul 31 19:34:19 2019] audit: type=1400 audit(1564616060.003:155): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/usr/sbin/tcpdump" pid=13941 comm="apparmor_parser"
[Wed Jul 31 19:34:19 2019] audit: type=1400 audit(1564616060.035:156): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/sbin/dhclient" pid=13937 comm="apparmor_parser"
[Wed Jul 31 19:34:19 2019] audit: type=1400 audit(1564616060.035:157): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/usr/lib/NetworkManager/nm-dhcp-client.action" pid=13937 comm="apparmor_parser"
[Wed Jul 31 19:34:34 2019] kauditd_printk_skb: 19 callbacks suppressed
[Wed Jul 31 19:34:34 2019] audit: type=1400 audit(1564616074.744:177): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.activate" pid=14601 comm="apparmor_parser"
[Wed Jul 31 19:34:34 2019] audit: type=1400 audit(1564616074.748:178): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.check-kernel" pid=14604 comm="apparmor_parser"
[Wed Jul 31 19:34:34 2019] audit: type=1400 audit(1564616074.752:179): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.benchmark" pid=14602 comm="apparmor_parser"
[Wed Jul 31 19:34:34 2019] audit: type=1400 audit(1564616074.752:180): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.buginfo" pid=14603 comm="apparmor_parser"
[Wed Jul 31 19:34:34 2019] audit: type=1400 audit(1564616074.948:181): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.lxc" pid=14608 comm="apparmor_parser"
[Wed Jul 31 19:34:34 2019] audit: type=1400 audit(1564616074.952:182): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.migrate" pid=14610 comm="apparmor_parser"
[Wed Jul 31 19:34:34 2019] audit: type=1400 audit(1564616074.952:183): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.lxd" pid=14609 comm="apparmor_parser"
[Wed Jul 31 19:34:34 2019] audit: type=1400 audit(1564616075.004:184): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.daemon" pid=14607 comm="apparmor_parser"
[Wed Jul 31 19:34:34 2019] audit: type=1400 audit(1564616075.012:185): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap-update-ns.lxd" pid=14612 comm="apparmor_parser"
[Wed Jul 31 19:34:34 2019] audit: type=1400 audit(1564616075.016:186): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.hook.install" pid=14614 comm="apparmor_parser"
[Wed Jul 31 19:35:28 2019] nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based  firewall rule not found. Use the iptables CT target to attach helpers instead.
[Thu Aug  1 10:27:27 2019] kauditd_printk_skb: 50 callbacks suppressed
[Thu Aug  1 10:27:27 2019] audit: type=1400 audit(1564669648.540:237): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="snap.lxd.benchmark" pid=31639 comm="apparmor_parser"
[Thu Aug  1 10:27:27 2019] audit: type=1400 audit(1564669648.540:238): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="snap.lxd.check-kernel" pid=31641 comm="apparmor_parser"
[Thu Aug  1 10:27:27 2019] audit: type=1400 audit(1564669648.544:239): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="snap.lxd.activate" pid=31638 comm="apparmor_parser"
[Thu Aug  1 10:27:27 2019] audit: type=1400 audit(1564669648.548:240): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="snap.lxd.buginfo" pid=31640 comm="apparmor_parser"
[Thu Aug  1 10:27:27 2019] audit: type=1400 audit(1564669648.728:241): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="snap.lxd.hook.install" pid=31644 comm="apparmor_parser"
[Thu Aug  1 10:27:27 2019] audit: type=1400 audit(1564669648.748:242): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="snap.lxd.lxc" pid=31645 comm="apparmor_parser"
[Thu Aug  1 10:27:27 2019] audit: type=1400 audit(1564669648.792:243): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="snap.lxd.hook.configure" pid=31643 comm="apparmor_parser"
[Thu Aug  1 10:27:27 2019] audit: type=1400 audit(1564669648.804:244): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="snap.lxd.daemon" pid=31642 comm="apparmor_parser"
[Thu Aug  1 10:27:27 2019] audit: type=1400 audit(1564669648.912:245): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="snap.lxd.lxd" pid=31646 comm="apparmor_parser"
[Thu Aug  1 10:27:28 2019] audit: type=1400 audit(1564669648.928:246): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="snap.lxd.migrate" pid=31647 comm="apparmor_parser"
[Thu Aug  1 12:43:48 2019] perf: interrupt took too long (2512 > 2500), lowering kernel.perf_event_max_sample_rate to 79500
[Thu Aug  1 12:47:38 2019] new mount options do not match the existing superblock, will be ignored
[Fri Aug  2 00:59:33 2019] perf: interrupt took too long (3166 > 3140), lowering kernel.perf_event_max_sample_rate to 63000
[Fri Aug  2 16:43:04 2019] perf: interrupt took too long (3979 > 3957), lowering kernel.perf_event_max_sample_rate to 50250
[Sat Aug  3 08:53:34 2019] [UFW BLOCK] IN=enp1s0 OUT= MAC=00:22:4d:1f:5a:2b:00:0d:b9:47:24:05:08:00 SRC=157.240.14.19 DST=10.167.10.8 LEN=91 TOS=0x00 PREC=0x00 TTL=83 ID=49842 DF PROTO=TCP SPT=443 DPT=50151 WINDOW=113 RES=0x00 ACK PSH URGP=0 
[Sat Aug  3 08:55:32 2019] [UFW BLOCK] IN=enp1s0 OUT= MAC=00:22:4d:1f:5a:2b:00:0d:b9:47:24:05:08:00 SRC=31.13.67.35 DST=10.167.10.8 LEN=91 TOS=0x00 PREC=0x00 TTL=83 ID=13193 DF PROTO=TCP SPT=443 DPT=50347 WINDOW=113 RES=0x00 ACK PSH URGP=0 
[Sat Aug  3 08:55:38 2019] [UFW BLOCK] IN=enp1s0 OUT= MAC=00:22:4d:1f:5a:2b:00:0d:b9:47:24:05:08:00 SRC=31.13.67.35 DST=10.167.10.8 LEN=91 TOS=0x00 PREC=0x00 TTL=83 ID=13200 DF PROTO=TCP SPT=443 DPT=50347 WINDOW=113 RES=0x00 ACK PSH FIN URGP=0 
[Sat Aug  3 08:55:44 2019] [UFW BLOCK] IN=enp1s0 OUT= MAC=00:22:4d:1f:5a:2b:00:0d:b9:47:24:05:08:00 SRC=31.13.67.35 DST=10.167.10.8 LEN=91 TOS=0x00 PREC=0x00 TTL=83 ID=13201 DF PROTO=TCP SPT=443 DPT=50347 WINDOW=113 RES=0x00 ACK PSH FIN URGP=0 
[Sat Aug  3 11:11:15 2019] perf: interrupt took too long (4982 > 4973), lowering kernel.perf_event_max_sample_rate to 40000
[Sun Aug  4 07:43:58 2019] kauditd_printk_skb: 12 callbacks suppressed
[Sun Aug  4 07:43:58 2019] audit: type=1400 audit(1564919042.385:259): apparmor="DENIED" operation="mount" info="failed flags match" error=-13 profile="lxd-disco_</var/snap/lxd/common/lxd>" name="/run/" pid=18838 comm="mount" flags="rw, nosuid, nodev, remount"
[Sun Aug  4 07:44:43 2019] br0: port 2(veth31XCZZ) entered disabled state
[Sun Aug  4 07:44:43 2019] device veth31XCZZ left promiscuous mode
[Sun Aug  4 07:44:43 2019] br0: port 2(veth31XCZZ) entered disabled state
[Sun Aug  4 07:45:31 2019] audit: type=1400 audit(1564919135.225:260): apparmor="STATUS" operation="profile_remove" profile="unconfined" name="lxd-disco_</var/snap/lxd/common/lxd>" pid=29094 comm="apparmor_parser"
[Sun Aug  4 07:53:02 2019] audit: type=1400 audit(1564919585.682:261): apparmor="DENIED" operation="open" profile="snap.lxd.hook.configure" name="/var/lib/snapd/hostfs/usr/lib/os-release" pid=29812 comm="snap-exec" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
[Sun Aug  4 07:53:02 2019] audit: type=1400 audit(1564919585.690:262): apparmor="DENIED" operation="open" profile="snap.lxd.hook.configure" name="/var/lib/snapd/hostfs/usr/lib/os-release" pid=29833 comm="snapctl" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
[Sun Aug  4 07:53:02 2019] audit: type=1400 audit(1564919585.698:263): apparmor="DENIED" operation="open" profile="snap.lxd.hook.configure" name="/var/lib/snapd/hostfs/usr/lib/os-release" pid=29841 comm="snapctl" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
[Sun Aug  4 07:53:02 2019] audit: type=1400 audit(1564919585.706:264): apparmor="DENIED" operation="open" profile="snap.lxd.hook.configure" name="/var/lib/snapd/hostfs/usr/lib/os-release" pid=29847 comm="snapctl" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
[Sun Aug  4 07:53:02 2019] audit: type=1400 audit(1564919585.718:265): apparmor="DENIED" operation="open" profile="snap.lxd.hook.configure" name="/var/lib/snapd/hostfs/usr/lib/os-release" pid=29856 comm="snapctl" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
[Sun Aug  4 07:53:02 2019] audit: type=1400 audit(1564919585.730:266): apparmor="DENIED" operation="open" profile="snap.lxd.hook.configure" name="/var/lib/snapd/hostfs/usr/lib/os-release" pid=29866 comm="snapctl" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
[Sun Aug  4 07:53:02 2019] audit: type=1400 audit(1564919585.738:267): apparmor="DENIED" operation="open" profile="snap.lxd.hook.configure" name="/var/lib/snapd/hostfs/usr/lib/os-release" pid=29875 comm="snapctl" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
[Sun Aug  4 07:53:24 2019] audit: type=1400 audit(1564919607.554:268): apparmor="STATUS" operation="profile_load" profile="unconfined" name="lxd-disco_</var/snap/lxd/common/lxd>" pid=30192 comm="apparmor_parser"
[Sun Aug  4 07:53:24 2019] br0: port 2(veth4VINYO) entered blocking state
[Sun Aug  4 07:53:24 2019] br0: port 2(veth4VINYO) entered disabled state
[Sun Aug  4 07:53:24 2019] device veth4VINYO entered promiscuous mode
[Sun Aug  4 07:53:24 2019] eth0: renamed from veth99YIUV
[Sun Aug  4 07:53:24 2019] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
[Sun Aug  4 07:53:24 2019] IPv6: ADDRCONF(NETDEV_CHANGE): veth4VINYO: link becomes ready
[Sun Aug  4 07:53:24 2019] br0: port 2(veth4VINYO) entered blocking state
[Sun Aug  4 07:53:24 2019] br0: port 2(veth4VINYO) entered forwarding state
[Sun Aug  4 07:53:24 2019] new mount options do not match the existing superblock, will be ignored
[Sun Aug  4 07:53:25 2019] audit: type=1400 audit(1564919608.478:269): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="nvidia_modprobe" pid=30821 comm="apparmor_parser"
[Sun Aug  4 07:53:25 2019] audit: type=1400 audit(1564919608.494:270): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="nvidia_modprobe//kmod" pid=30821 comm="apparmor_parser"
[Sun Aug  4 07:53:25 2019] audit: type=1400 audit(1564919608.494:271): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/usr/bin/man" pid=30824 comm="apparmor_parser"
[Sun Aug  4 07:53:25 2019] audit: type=1400 audit(1564919608.498:272): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="man_filter" pid=30824 comm="apparmor_parser"
[Sun Aug  4 07:53:25 2019] audit: type=1400 audit(1564919608.498:273): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="man_groff" pid=30824 comm="apparmor_parser"
[Sun Aug  4 07:53:25 2019] audit: type=1400 audit(1564919608.550:274): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/sbin/dhclient" pid=30823 comm="apparmor_parser"
[Sun Aug  4 07:53:25 2019] audit: type=1400 audit(1564919608.554:275): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/usr/lib/NetworkManager/nm-dhcp-client.action" pid=30823 comm="apparmor_parser"
[Sun Aug  4 07:53:25 2019] audit: type=1400 audit(1564919608.554:276): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/usr/lib/NetworkManager/nm-dhcp-helper" pid=30823 comm="apparmor_parser"
[Sun Aug  4 07:53:25 2019] audit: type=1400 audit(1564919608.554:277): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/usr/lib/connman/scripts/dhclient-script" pid=30823 comm="apparmor_parser"
[Sun Aug  4 07:53:45 2019] kauditd_printk_skb: 3 callbacks suppressed
[Sun Aug  4 07:53:45 2019] audit: type=1400 audit(1564919629.183:281): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/snap/core/7270/usr/lib/snapd/snap-confine" pid=32183 comm="apparmor_parser"
[Sun Aug  4 07:53:45 2019] audit: type=1400 audit(1564919629.183:282): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/snap/core/7270/usr/lib/snapd/snap-confine//mount-namespace-capture-helper" pid=32183 comm="apparmor_parser"
[Sun Aug  4 07:53:45 2019] audit: type=1400 audit(1564919629.231:283): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap-update-ns.core" pid=32185 comm="apparmor_parser"
[Sun Aug  4 07:53:45 2019] audit: type=1400 audit(1564919629.367:284): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.core.hook.configure" pid=32186 comm="apparmor_parser"
[Sun Aug  4 07:53:49 2019] audit: type=1400 audit(1564919633.031:285): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/snap/core/7270/usr/lib/snapd/snap-confine" pid=32296 comm="apparmor_parser"
[Sun Aug  4 07:53:49 2019] audit: type=1400 audit(1564919633.055:286): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="/snap/core/7270/usr/lib/snapd/snap-confine//mount-namespace-capture-helper" pid=32296 comm="apparmor_parser"
[Sun Aug  4 07:53:49 2019] audit: type=1400 audit(1564919633.067:287): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap-update-ns.core" pid=32298 comm="apparmor_parser"
[Sun Aug  4 07:53:49 2019] audit: type=1400 audit(1564919633.067:288): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.core.hook.configure" pid=32299 comm="apparmor_parser"
[Sun Aug  4 07:53:59 2019] audit: type=1400 audit(1564919642.475:289): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap-update-ns.lxd" pid=32541 comm="apparmor_parser"
[Sun Aug  4 07:53:59 2019] audit: type=1400 audit(1564919642.631:290): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.benchmark" pid=32543 comm="apparmor_parser"
[Sun Aug  4 07:53:59 2019] audit: type=1400 audit(1564919642.651:291): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.buginfo" pid=32544 comm="apparmor_parser"
[Sun Aug  4 07:53:59 2019] audit: type=1400 audit(1564919642.667:292): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.activate" pid=32542 comm="apparmor_parser"
[Sun Aug  4 07:53:59 2019] audit: type=1400 audit(1564919642.735:293): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.check-kernel" pid=32545 comm="apparmor_parser"
[Sun Aug  4 07:53:59 2019] audit: type=1400 audit(1564919642.803:294): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.daemon" pid=32546 comm="apparmor_parser"
[Sun Aug  4 07:53:59 2019] audit: type=1400 audit(1564919642.871:295): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.hook.configure" pid=32547 comm="apparmor_parser"
[Sun Aug  4 07:53:59 2019] audit: type=1400 audit(1564919642.895:296): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.hook.install" pid=32548 comm="apparmor_parser"
[Sun Aug  4 07:53:59 2019] audit: type=1400 audit(1564919642.963:297): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.lxc" pid=32549 comm="apparmor_parser"
[Sun Aug  4 07:53:59 2019] audit: type=1400 audit(1564919642.975:298): apparmor="STATUS" operation="profile_load" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.lxd" pid=32550 comm="apparmor_parser"
[Sun Aug  4 07:54:04 2019] kauditd_printk_skb: 61 callbacks suppressed
[Sun Aug  4 07:54:04 2019] audit: type=1400 audit(1564919647.739:360): apparmor="DENIED" operation="file_inherit" namespace="root//lxd-disco_<var-snap-lxd-common-lxd>" profile="/snap/core/7270/usr/lib/snapd/snap-confine" pid=363 comm="snap-confine" family="netlink" sock_type="raw" protocol=15 requested_mask="send receive" denied_mask="send receive"
[Sun Aug  4 07:54:04 2019] audit: type=1400 audit(1564919647.763:361): apparmor="DENIED" operation="file_inherit" namespace="root//lxd-disco_<var-snap-lxd-common-lxd>" profile="snap-update-ns.lxd" name="/apparmor/.null" pid=379 comm="6" requested_mask="wr" denied_mask="wr" fsuid=1000000 ouid=0
[Sun Aug  4 07:54:04 2019] audit: type=1400 audit(1564919648.087:362): apparmor="DENIED" operation="file_inherit" namespace="root//lxd-disco_<var-snap-lxd-common-lxd>" profile="snap.lxd.hook.install" name="/apparmor/.null" pid=363 comm="snap-exec" requested_mask="wr" denied_mask="wr" fsuid=1000000 ouid=0
[Sun Aug  4 07:54:06 2019] audit: type=1400 audit(1564919649.819:363): apparmor="DENIED" operation="file_inherit" namespace="root//lxd-disco_<var-snap-lxd-common-lxd>" profile="/snap/core/7270/usr/lib/snapd/snap-confine" pid=557 comm="snap-confine" family="netlink" sock_type="raw" protocol=15 requested_mask="send receive" denied_mask="send receive"
[Sun Aug  4 07:54:06 2019] audit: type=1400 audit(1564919649.831:364): apparmor="DENIED" operation="file_inherit" namespace="root//lxd-disco_<var-snap-lxd-common-lxd>" profile="snap.lxd.hook.configure" name="/apparmor/.null" pid=557 comm="snap-exec" requested_mask="wr" denied_mask="wr" fsuid=1000000 ouid=0
[Sun Aug  4 07:54:36 2019] audit: type=1400 audit(1564919679.479:365): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.hook.configure" pid=1490 comm="apparmor_parser"
[Sun Aug  4 07:54:36 2019] audit: type=1400 audit(1564919679.487:366): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap-update-ns.lxd" pid=1492 comm="apparmor_parser"
[Sun Aug  4 07:54:36 2019] audit: type=1400 audit(1564919679.491:367): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.activate" pid=1493 comm="apparmor_parser"
[Sun Aug  4 07:54:36 2019] audit: type=1400 audit(1564919679.491:368): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.benchmark" pid=1494 comm="apparmor_parser"
[Sun Aug  4 07:54:36 2019] audit: type=1400 audit(1564919679.491:369): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.check-kernel" pid=1496 comm="apparmor_parser"
[Sun Aug  4 07:54:36 2019] audit: type=1400 audit(1564919679.495:370): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.buginfo" pid=1495 comm="apparmor_parser"
[Sun Aug  4 07:54:36 2019] audit: type=1400 audit(1564919679.495:371): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.hook.install" pid=1498 comm="apparmor_parser"
[Sun Aug  4 07:54:36 2019] audit: type=1400 audit(1564919679.495:372): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.daemon" pid=1497 comm="apparmor_parser"
[Sun Aug  4 07:54:36 2019] audit: type=1400 audit(1564919679.499:373): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.lxd" pid=1500 comm="apparmor_parser"
[Sun Aug  4 07:54:36 2019] audit: type=1400 audit(1564919679.499:374): apparmor="STATUS" operation="profile_replace" info="same as current profile, skipping" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.lxc" pid=1499 comm="apparmor_parser"
[Sun Aug  4 07:54:41 2019] kauditd_printk_skb: 20 callbacks suppressed
[Sun Aug  4 07:54:41 2019] audit: type=1400 audit(1564919684.999:395): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.activate" pid=1709 comm="apparmor_parser"
[Sun Aug  4 07:54:41 2019] audit: type=1400 audit(1564919684.999:396): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.benchmark" pid=1710 comm="apparmor_parser"
[Sun Aug  4 07:54:41 2019] audit: type=1400 audit(1564919685.003:397): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.buginfo" pid=1711 comm="apparmor_parser"
[Sun Aug  4 07:54:41 2019] audit: type=1400 audit(1564919685.003:398): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.check-kernel" pid=1712 comm="apparmor_parser"
[Sun Aug  4 07:54:41 2019] audit: type=1400 audit(1564919685.183:399): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.hook.install" pid=1715 comm="apparmor_parser"
[Sun Aug  4 07:54:41 2019] audit: type=1400 audit(1564919685.183:400): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.lxc" pid=1716 comm="apparmor_parser"
[Sun Aug  4 07:54:41 2019] audit: type=1400 audit(1564919685.183:401): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.hook.configure" pid=1714 comm="apparmor_parser"
[Sun Aug  4 07:54:41 2019] audit: type=1400 audit(1564919685.247:402): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.daemon" pid=1713 comm="apparmor_parser"
[Sun Aug  4 07:54:41 2019] audit: type=1400 audit(1564919685.335:403): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.migrate" pid=1718 comm="apparmor_parser"
[Sun Aug  4 07:54:41 2019] audit: type=1400 audit(1564919685.339:404): apparmor="STATUS" operation="profile_replace" label="lxd-disco_</var/snap/lxd/common/lxd>//&:lxd-disco_<var-snap-lxd-common-lxd>:unconfined" name="snap.lxd.lxd" pid=1717 comm="apparmor_parser"
[Sun Aug  4 07:55:34 2019] nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based  firewall rule not found. Use the iptables CT target to attach helpers instead.
[Sun Aug  4 18:21:19 2019] perf: interrupt took too long (6254 > 6227), lowering kernel.perf_event_max_sample_rate to 31750

Odd, so you’re not hitting any obvious kernel bug at least.

It may be interesting to reproduce your issue, then when you get the stuck process, do cat /proc/PID/stack which should show where exactly the process is stuck.

I’m running a shiftfs and non-shiftfs container side-by-side to see if the problem recurs. Below is output from zfs list edited to remove some very long lines. Both container datasets are clones of the same image snapshot but the space used by the shiftfs container is much higher. This pool uses lz4 compression.

I know that figuring out ZFS disk usage can be confusing, but this looks like using shiftfs causes the entire image to be more than duplicated.

NAME                               USED  AVAIL  REFER
pool/lxd/containers/disco         87.3M  26.0G   558M
pool/lxd/containers/disco-shiftfs  822M  26.0G  1.27G
pool/lxd/images/<removed>          483M  26.0G   483M

That’s quite a bit larger than the image too, can you run du -sch -x / inside both containers?

Both produced identical output:

571M    /
571M    total

That’s odd. With both containers started, can you run the same du but this time against /var/snap/lxd/common/mntns/var/snap/lxd/common/lxd/storage-pools/default/containers/NAME ?

Both commands return 571M.

Here’s something else odd. After some routine package updates the shiftfs container appears to be consuming pool space at a faster rate:

NAME                                USED  AVAIL  REFER
pool/lxd/containers/disco           105M  25.6G   562M
pool/lxd/containers/disco-shiftfs  1.24G  25.6G  1.69G

/var/log/apt/history.log shows the updates to each container were identical. The only snap installed is core.

That’s very weird because the du output for the storage-pool volume entry should have been an identical match to filesystem usage… So I wonder exactly what zfs is tracking here.

I’m assuming that disco-shiftfs doesn’t have any snapshots right?

Might also be interesting to see zfs get all pool/lxd/containers/disco and pool/lxd/containers/disco-shiftfs

NAME                       PROPERTY               VALUE                                                                                      SOURCE
pool/lxd/containers/disco  type                   filesystem                                                                                 -
pool/lxd/containers/disco  creation               Sun Aug  4  7:53 2019                                                                      -
pool/lxd/containers/disco  used                   105M                                                                                       -
pool/lxd/containers/disco  available              25.6G                                                                                      -
pool/lxd/containers/disco  referenced             562M                                                                                       -
pool/lxd/containers/disco  compressratio          2.18x                                                                                      -
pool/lxd/containers/disco  mounted                no                                                                                         -
pool/lxd/containers/disco  origin                 pool/lxd/images/4b6301a6704253ff5e1a12c8521b55d8dcafad30f218b65edcb78ee3e110bf74@readonly  -
pool/lxd/containers/disco  quota                  none                                                                                       local
pool/lxd/containers/disco  reservation            none                                                                                       default
pool/lxd/containers/disco  recordsize             128K                                                                                       default
pool/lxd/containers/disco  mountpoint             /var/snap/lxd/common/lxd/storage-pools/default/containers/disco                            local
pool/lxd/containers/disco  sharenfs               off                                                                                        default
pool/lxd/containers/disco  checksum               on                                                                                         default
pool/lxd/containers/disco  compression            lz4                                                                                        inherited from pool
pool/lxd/containers/disco  atime                  on                                                                                         default
pool/lxd/containers/disco  devices                on                                                                                         inherited from pool/lxd
pool/lxd/containers/disco  exec                   on                                                                                         inherited from pool/lxd
pool/lxd/containers/disco  setuid                 on                                                                                         inherited from pool/lxd
pool/lxd/containers/disco  readonly               off                                                                                        default
pool/lxd/containers/disco  zoned                  off                                                                                        default
pool/lxd/containers/disco  snapdir                hidden                                                                                     default
pool/lxd/containers/disco  aclinherit             restricted                                                                                 default
pool/lxd/containers/disco  createtxg              8033064                                                                                    -
pool/lxd/containers/disco  canmount               noauto                                                                                     local
pool/lxd/containers/disco  xattr                  sa                                                                                         inherited from pool/lxd
pool/lxd/containers/disco  copies                 1                                                                                          default
pool/lxd/containers/disco  version                5                                                                                          -
pool/lxd/containers/disco  utf8only               off                                                                                        -
pool/lxd/containers/disco  normalization          none                                                                                       -
pool/lxd/containers/disco  casesensitivity        sensitive                                                                                  -
pool/lxd/containers/disco  vscan                  off                                                                                        default
pool/lxd/containers/disco  nbmand                 off                                                                                        default
pool/lxd/containers/disco  sharesmb               off                                                                                        default
pool/lxd/containers/disco  refquota               none                                                                                       default
pool/lxd/containers/disco  refreservation         none                                                                                       default
pool/lxd/containers/disco  guid                   5458112912204137206                                                                        -
pool/lxd/containers/disco  primarycache           all                                                                                        default
pool/lxd/containers/disco  secondarycache         all                                                                                        default
pool/lxd/containers/disco  usedbysnapshots        0B                                                                                         -
pool/lxd/containers/disco  usedbydataset          105M                                                                                       -
pool/lxd/containers/disco  usedbychildren         0B                                                                                         -
pool/lxd/containers/disco  usedbyrefreservation   0B                                                                                         -
pool/lxd/containers/disco  logbias                latency                                                                                    default
pool/lxd/containers/disco  dedup                  off                                                                                        default
pool/lxd/containers/disco  mlslabel               none                                                                                       default
pool/lxd/containers/disco  sync                   standard                                                                                   default
pool/lxd/containers/disco  dnodesize              legacy                                                                                     default
pool/lxd/containers/disco  refcompressratio       1.74x                                                                                      -
pool/lxd/containers/disco  written                105M                                                                                       -
pool/lxd/containers/disco  logicalused            222M                                                                                       -
pool/lxd/containers/disco  logicalreferenced      971M                                                                                       -
pool/lxd/containers/disco  volmode                default                                                                                    default
pool/lxd/containers/disco  filesystem_limit       none                                                                                       default
pool/lxd/containers/disco  snapshot_limit         none                                                                                       default
pool/lxd/containers/disco  filesystem_count       none                                                                                       default
pool/lxd/containers/disco  snapshot_count         none                                                                                       default
pool/lxd/containers/disco  snapdev                hidden                                                                                     default
pool/lxd/containers/disco  acltype                posixacl                                                                                   inherited from pool/lxd
pool/lxd/containers/disco  context                none                                                                                       default
pool/lxd/containers/disco  fscontext              none                                                                                       default
pool/lxd/containers/disco  defcontext             none                                                                                       default
pool/lxd/containers/disco  rootcontext            none                                                                                       default
pool/lxd/containers/disco  relatime               off                                                                                        default
pool/lxd/containers/disco  redundant_metadata     all                                                                                        default
pool/lxd/containers/disco  overlay                off                                                                                        default
pool/lxd/containers/disco  com.sun:auto-snapshot  false                                                                                      inherited from pool
NAME                               PROPERTY               VALUE                                                                                      SOURCE
pool/lxd/containers/disco-shiftfs  type                   filesystem                                                                                 -
pool/lxd/containers/disco-shiftfs  creation               Mon Aug  5 11:07 2019                                                                      -
pool/lxd/containers/disco-shiftfs  used                   1.24G                                                                                      -
pool/lxd/containers/disco-shiftfs  available              25.6G                                                                                      -
pool/lxd/containers/disco-shiftfs  referenced             1.70G                                                                                      -
pool/lxd/containers/disco-shiftfs  compressratio          1.67x                                                                                      -
pool/lxd/containers/disco-shiftfs  mounted                no                                                                                         -
pool/lxd/containers/disco-shiftfs  origin                 pool/lxd/images/4b6301a6704253ff5e1a12c8521b55d8dcafad30f218b65edcb78ee3e110bf74@readonly  -
pool/lxd/containers/disco-shiftfs  quota                  none                                                                                       local
pool/lxd/containers/disco-shiftfs  reservation            none                                                                                       default
pool/lxd/containers/disco-shiftfs  recordsize             128K                                                                                       default
pool/lxd/containers/disco-shiftfs  mountpoint             /var/snap/lxd/common/lxd/storage-pools/default/containers/disco-shiftfs                    local
pool/lxd/containers/disco-shiftfs  sharenfs               off                                                                                        default
pool/lxd/containers/disco-shiftfs  checksum               on                                                                                         default
pool/lxd/containers/disco-shiftfs  compression            lz4                                                                                        inherited from pool
pool/lxd/containers/disco-shiftfs  atime                  on                                                                                         default
pool/lxd/containers/disco-shiftfs  devices                on                                                                                         inherited from pool/lxd
pool/lxd/containers/disco-shiftfs  exec                   on                                                                                         inherited from pool/lxd
pool/lxd/containers/disco-shiftfs  setuid                 on                                                                                         inherited from pool/lxd
pool/lxd/containers/disco-shiftfs  readonly               off                                                                                        default
pool/lxd/containers/disco-shiftfs  zoned                  off                                                                                        default
pool/lxd/containers/disco-shiftfs  snapdir                hidden                                                                                     default
pool/lxd/containers/disco-shiftfs  aclinherit             restricted                                                                                 default
pool/lxd/containers/disco-shiftfs  createtxg              8052330                                                                                    -
pool/lxd/containers/disco-shiftfs  canmount               noauto                                                                                     local
pool/lxd/containers/disco-shiftfs  xattr                  sa                                                                                         inherited from pool/lxd
pool/lxd/containers/disco-shiftfs  copies                 1                                                                                          default
pool/lxd/containers/disco-shiftfs  version                5                                                                                          -
pool/lxd/containers/disco-shiftfs  utf8only               off                                                                                        -
pool/lxd/containers/disco-shiftfs  normalization          none                                                                                       -
pool/lxd/containers/disco-shiftfs  casesensitivity        sensitive                                                                                  -
pool/lxd/containers/disco-shiftfs  vscan                  off                                                                                        default
pool/lxd/containers/disco-shiftfs  nbmand                 off                                                                                        default
pool/lxd/containers/disco-shiftfs  sharesmb               off                                                                                        default
pool/lxd/containers/disco-shiftfs  refquota               none                                                                                       default
pool/lxd/containers/disco-shiftfs  refreservation         none                                                                                       default
pool/lxd/containers/disco-shiftfs  guid                   5217981688024002070                                                                        -
pool/lxd/containers/disco-shiftfs  primarycache           all                                                                                        default
pool/lxd/containers/disco-shiftfs  secondarycache         all                                                                                        default
pool/lxd/containers/disco-shiftfs  usedbysnapshots        0B                                                                                         -
pool/lxd/containers/disco-shiftfs  usedbydataset          1.24G                                                                                      -
pool/lxd/containers/disco-shiftfs  usedbychildren         0B                                                                                         -
pool/lxd/containers/disco-shiftfs  usedbyrefreservation   0B                                                                                         -
pool/lxd/containers/disco-shiftfs  logbias                latency                                                                                    default
pool/lxd/containers/disco-shiftfs  dedup                  off                                                                                        default
pool/lxd/containers/disco-shiftfs  mlslabel               none                                                                                       default
pool/lxd/containers/disco-shiftfs  sync                   standard                                                                                   default
pool/lxd/containers/disco-shiftfs  dnodesize              legacy                                                                                     default
pool/lxd/containers/disco-shiftfs  refcompressratio       1.67x                                                                                      -
pool/lxd/containers/disco-shiftfs  written                1.24G                                                                                      -
pool/lxd/containers/disco-shiftfs  logicalused            2.08G                                                                                      -
pool/lxd/containers/disco-shiftfs  logicalreferenced      2.84G                                                                                      -
pool/lxd/containers/disco-shiftfs  volmode                default                                                                                    default
pool/lxd/containers/disco-shiftfs  filesystem_limit       none                                                                                       default
pool/lxd/containers/disco-shiftfs  snapshot_limit         none                                                                                       default
pool/lxd/containers/disco-shiftfs  filesystem_count       none                                                                                       default
pool/lxd/containers/disco-shiftfs  snapshot_count         none                                                                                       default
pool/lxd/containers/disco-shiftfs  snapdev                hidden                                                                                     default
pool/lxd/containers/disco-shiftfs  acltype                posixacl                                                                                   inherited from pool/lxd
pool/lxd/containers/disco-shiftfs  context                none                                                                                       default
pool/lxd/containers/disco-shiftfs  fscontext              none                                                                                       default
pool/lxd/containers/disco-shiftfs  defcontext             none                                                                                       default
pool/lxd/containers/disco-shiftfs  rootcontext            none                                                                                       default
pool/lxd/containers/disco-shiftfs  relatime               off                                                                                        default
pool/lxd/containers/disco-shiftfs  redundant_metadata     all                                                                                        default
pool/lxd/containers/disco-shiftfs  overlay                off                                                                                        default
pool/lxd/containers/disco-shiftfs  com.sun:auto-snapshot  false                                                                                      inherited from pool

My observations of shiftfs storage use so far have been on an existing physical server. I thought I would try to recreate the behavior on a newly created virtual system. Here’s what I did:

  • Install Bionic Server in VirtualBox (on a Mac) with 2 virtual disks
  • Upgrade to HWE kernel
  • Initialize ZFS on 2nd virtual disk (using lz4)
  • Migrate to LXD snap
  • Initialize LXD to use ZFS dataset and default bridge
  • Launch container disco
  • Enable shiftfs
  • Launch container disco-shiftfs

Immediately after launch:

NAME                                USED  AVAIL  REFER
pool/lxd/containers/disco          8.07M  3.36G   484M
pool/lxd/containers/disco-shiftfs  5.64M  3.36G   487M

After updating the few outdated packages:

NAME                                USED  AVAIL  REFER
pool/lxd/containers/disco           104M  3.04G   560M
pool/lxd/containers/disco-shiftfs   233M  3.04G   712M

After installing build-essential:

NAME                                USED  AVAIL  REFER
pool/lxd/containers/disco           191M  2.80G   648M
pool/lxd/containers/disco-shiftfs   393M  2.80G   872M

At this point du -sch -x / still matches from inside each container at 660M.

Hopefully this helps with recreating the issue.

@brauner any ideas as to what may be going on here?