I installed new ISO build manjaro-kde-21.1-stable-staging-210816-linux513.iso having stable-staging branch settings.
BTRFS+LUKS was chosen (all operations via GUI installer and auto-partitioning used)).
Switched to unstable branch and updated it.
I found that saved log which I wanted to report: may be it can be helpful for someone developer.
It is very first / initial update after clean ISO installation.
Pacman's log key excerpt:
E: ERROR: can't list qgroups: quotas not enabled
E: btrfs returned an error: 256
E: Failed to query subvolume quota
Enabled subvolume quota support
Complete log
$ sudo pacman-mirrors -c Netherlands -P https -B unstable -a
::INFO Branch in config is changed
::INFO Protocols in config is changed
::WARNING https://repo.manjaro.org 'Connection: HTTPSConnectionPool(host='repo.manjaro.org', port=443): Max retries exceeded with url: / (Caused by NewConnectionError('<urllib3.connection.HTTPSConnection object at 0x7f9f2f3680d0>: Failed to establish a new connection: [Errno -2] Name or service not known'))'
::WARNING https://wikipedia.org 'Connection: HTTPSConnectionPool(host='wikipedia.org', port=443): Max retries exceeded with url: / (Caused by NewConnectionError('<urllib3.connection.HTTPSConnection object at 0x7f9f2da3b6d0>: Failed to establish a new connection: [Errno -2] Name or service not known'))'
::WARNING https://bitbucket.org 'Connection: HTTPSConnectionPool(host='bitbucket.org', port=443): Max retries exceeded with url: / (Caused by NewConnectionError('<urllib3.connection.HTTPSConnection object at 0x7f9f2da3b310>: Failed to establish a new connection: [Errno -2] Name or service not known'))'
::INFO Internet connection appears to be down
::INFO Mirror ranking is not available
::INFO Mirror list is generated using random method
::INFO User generated mirror list
::------------------------------------------------------------
::INFO Custom mirror file saved: /var/lib/pacman-mirrors/custom-mirrors.json
::INFO Writing mirror list
::Netherlands : https://ftp.nluug.nl/pub/os/Linux/distr/manjaro/unstable/$repo/$arch
::Netherlands : https://mirror.koddos.net/manjaro/unstable/$repo/$arch
::INFO Mirror list generated and saved to: /etc/pacman.d/mirrorlist
::INFO To reset custom mirrorlist 'sudo pacman-mirrors -id'
::INFO To remove custom config run 'sudo pacman-mirrors -c all'
$ ping 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
From 172.27.235.73 icmp_seq=1 Destination Net Unreachable
From 172.27.235.73 icmp_seq=2 Destination Net Unreachable
From 172.27.235.73 icmp_seq=3 Destination Net Unreachable
^C
--- 8.8.8.8 ping statistics ---
3 packets transmitted, 0 received, +3 errors, 100% packet loss, time 2020ms
$ ping 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=103 time=39.1 ms
64 bytes from 8.8.8.8: icmp_seq=2 ttl=103 time=39.8 ms
^C
--- 8.8.8.8 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1000ms
rtt min/avg/max/mdev = 39.133/39.467/39.801/0.334 ms
$ sudo pacman-mirrors -c Netherlands -P https -a -B unstable
::INFO Branch in config is changed
::INFO Protocols in config is changed
::INFO Downloading mirrors from Manjaro
::INFO => Mirror pool: https://repo.manjaro.org/mirrors.json
::INFO => Mirror status: http://repo.manjaro.org/status.json
::INFO User generated mirror list
::------------------------------------------------------------
::INFO Custom mirror file saved: /var/lib/pacman-mirrors/custom-mirrors.json
::INFO Using custom mirror file
::INFO Querying mirrors - This may take some time
1.463 Netherlands : https://mirror.erickochen.nl/manjaro/
3.169 Netherlands : https://manjaro.mirrors.lavatech.top/
1.547 Netherlands : https://ftp.nluug.nl/pub/os/Linux/distr/manjaro/
0.787 Netherlands : https://mirror.koddos.net/manjaro/
::INFO Writing mirror list
::Netherlands : https://mirror.koddos.net/manjaro/unstable/$repo/$arch
::Netherlands : https://mirror.erickochen.nl/manjaro/unstable/$repo/$arch
::Netherlands : https://ftp.nluug.nl/pub/os/Linux/distr/manjaro/unstable/$repo/$arch
::Netherlands : https://manjaro.mirrors.lavatech.top/unstable/$repo/$arch
::INFO Mirror list generated and saved to: /etc/pacman.d/mirrorlist
::INFO To reset custom mirrorlist 'sudo pacman-mirrors -id'
::INFO To remove custom config run 'sudo pacman-mirrors -c all'
$ sudo pacman-mirrors -c Netherlands -P https -a -B unstable
::INFO Branch in config is changed
::INFO Protocols in config is changed
::INFO Downloading mirrors from Manjaro
::INFO => Mirror pool: https://repo.manjaro.org/mirrors.json
::INFO => Mirror status: http://repo.manjaro.org/status.json
::INFO User generated mirror list
::------------------------------------------------------------
::INFO Custom mirror file saved: /var/lib/pacman-mirrors/custom-mirrors.json
::INFO Using custom mirror file
::INFO Querying mirrors - This may take some time
0.482 Netherlands : https://mirror.erickochen.nl/manjaro/
2.444 Netherlands : https://manjaro.mirrors.lavatech.top/
0.630 Netherlands : https://ftp.nluug.nl/pub/os/Linux/distr/manjaro/
0.688 Netherlands : https://mirror.koddos.net/manjaro/
::INFO Writing mirror list
::Netherlands : https://mirror.erickochen.nl/manjaro/unstable/$repo/$arch
::Netherlands : https://ftp.nluug.nl/pub/os/Linux/distr/manjaro/unstable/$repo/$arch
::Netherlands : https://mirror.koddos.net/manjaro/unstable/$repo/$arch
::Netherlands : https://manjaro.mirrors.lavatech.top/unstable/$repo/$arch
::INFO Mirror list generated and saved to: /etc/pacman.d/mirrorlist
::INFO To reset custom mirrorlist 'sudo pacman-mirrors -id'
::INFO To remove custom config run 'sudo pacman-mirrors -c all'
$ sudo pacman -Syu
:: Synchronising package databases...
core 169.4 KiB 204 KiB/s 00:01 [####################################################################] 100%
extra 1886.4 KiB 927 KiB/s 00:02 [####################################################################] 100%
community 6.6 MiB 1303 KiB/s 00:05 [####################################################################] 100%
multilib 176.2 KiB 177 KiB/s 00:01 [####################################################################] 100%
:: Starting full system upgrade...
resolving dependencies...
looking for conflicting packages...
Package (9) Old Version New Version Net Change Download Size
multilib/lib32-systemd 248.7-1 249.3-1 0.08 MiB 0.78 MiB
extra/libpamac 11.0.1-3 11.1.0beta-2 0.21 MiB 0.83 MiB
extra/libpamac-flatpak-plugin 11.0.1-2 11.1.0beta-2 0.00 MiB 0.04 MiB
extra/libpamac-snap-plugin 11.0.1-2 11.1.0beta-2 0.00 MiB 0.03 MiB
extra/pamac-cli 10.1.3-3 10.2.0beta-1 0.00 MiB 0.08 MiB
extra/pamac-gtk 10.1.3-3 10.2.0beta-1 0.01 MiB 0.22 MiB
core/systemd 248.7-1 249.3-1 0.66 MiB 8.56 MiB
core/systemd-libs 248.7-1 249.3-1 0.10 MiB 0.77 MiB
core/systemd-sysvcompat 248.7-1 249.3-1 0.00 MiB 0.01 MiB
Total Download Size: 11.31 MiB
Total Installed Size: 34.83 MiB
Net Upgrade Size: 1.06 MiB
:: Proceed with installation? [Y/n]
:: Retrieving packages...
systemd-sysvcompat-249.3-1-x86_64 6.2 KiB 5.94 KiB/s 00:01 [####################################################################] 100%
lib32-systemd-249.3-1-x86_64 798.8 KiB 722 KiB/s 00:01 [####################################################################] 100%
libpamac-flatpak-plugin-11.1.0beta-2-x86_64 39.6 KiB 30.0 KiB/s 00:01 [####################################################################] 100%
libpamac-snap-plugin-11.1.0beta-2-x86_64 35.5 KiB 24.3 KiB/s 00:01 [####################################################################] 100%
libpamac-11.1.0beta-2-x86_64 849.6 KiB 257 KiB/s 00:03 [####################################################################] 100%
systemd-libs-249.3-1-x86_64 785.4 KiB 237 KiB/s 00:03 [####################################################################] 100%
pamac-cli-10.2.0beta-1-x86_64 78.1 KiB 21.1 KiB/s 00:04 [####################################################################] 100%
systemd-249.3-1-x86_64 8.6 MiB 1281 KiB/s 00:07 [####################################################################] 100%
pamac-gtk-10.2.0beta-1-x86_64 221.5 KiB 29.8 KiB/s 00:07 [####################################################################] 100%
Total (9/9) 11.3 MiB 1539 KiB/s 00:08 [####################################################################] 100%
(9/9) checking keys in keyring [####################################################################] 100%
(9/9) checking package integrity [####################################################################] 100%
(9/9) loading package files [####################################################################] 100%
(9/9) checking for file conflicts [####################################################################] 100%
(9/9) checking available disk space [####################################################################] 100%
:: Running pre-transaction hooks...
(1/1) Creating Timeshift snapshot before upgrade...
First run mode (config file not found)
Selected default snapshot type: BTRFS
Using system disk as snapshot device for creating snapshots in BTRFS mode
Mounted '/dev/dm-0 (nvme0n1p2)' at '/run/timeshift/backup'
Creating new backup...(BTRFS)
Saving to device: /dev/dm-0, mounted at path: /run/timeshift/backup
Created directory: /run/timeshift/backup/timeshift-btrfs/snapshots/2021-08-17_15-09-52
Created subvolume snapshot: /run/timeshift/backup/timeshift-btrfs/snapshots/2021-08-17_15-09-52/@
Created control file: /run/timeshift/backup/timeshift-btrfs/snapshots/2021-08-17_15-09-52/info.json
BTRFS Snapshot saved successfully (0s)
Tagged snapshot '2021-08-17_15-09-52': ondemand
------------------------------------------------------------------------------
E: ERROR: can't list qgroups: quotas not enabled
E: btrfs returned an error: 256
E: Failed to query subvolume quota
Enabled subvolume quota support
Generating grub configuration file ...
Found theme: /usr/share/grub/themes/manjaro/theme.txt
Found linux image: /boot/vmlinuz-5.13-x86_64
Found initrd image: /boot/intel-ucode.img /boot/initramfs-5.13-x86_64.img
Found initrd fallback image: /boot/initramfs-5.13-x86_64-fallback.img
Warning: os-prober will not be executed to detect other bootable partitions.
Systems on them will not be added to the GRUB boot configuration.
Check GRUB_DISABLE_OS_PROBER documentation entry.
Adding boot menu entry for UEFI Firmware Settings ...
Detecting snapshots ...
Info: Separate boot partition not detected
Found snapshot: 2021-08-17 15:09:52 | timeshift-btrfs/snapshots/2021-08-17_15-09-52/@
Found 1 snapshot(s)
Found memtest86+ image: /boot/memtest86+/memtest.bin
done
:: Processing package changes...
(1/9) upgrading systemd-libs [####################################################################] 100%
(2/9) upgrading systemd [####################################################################] 100%
(3/9) upgrading lib32-systemd [####################################################################] 100%
(4/9) upgrading libpamac [####################################################################] 100%
(5/9) upgrading libpamac-flatpak-plugin [####################################################################] 100%
(6/9) upgrading libpamac-snap-plugin [####################################################################] 100%
(7/9) upgrading pamac-cli [####################################################################] 100%
(8/9) upgrading pamac-gtk [####################################################################] 100%
(9/9) upgrading systemd-sysvcompat [####################################################################] 100%
:: Running post-transaction hooks...
( 1/14) Creating system user accounts...
( 2/14) Updating journal message catalog...
( 3/14) Reloading system manager configuration...
( 4/14) Updating udev hardware database...
( 5/14) Applying kernel sysctl settings...
( 6/14) Creating temporary files...
( 7/14) Reloading device manager configuration...
( 8/14) Arming ConditionNeedsUpdate...
( 9/14) Updating linux initcpios...
==> Building image from preset: /etc/mkinitcpio.d/linux513.preset: 'default'
-> -k /boot/vmlinuz-5.13-x86_64 -c /etc/mkinitcpio.conf -g /boot/initramfs-5.13-x86_64.img
==> Starting build: 5.13.11-1-MANJARO
-> Running build hook: [base]
-> Running build hook: [udev]
-> Running build hook: [autodetect]
-> Running build hook: [modconf]
-> Running build hook: [block]
-> Running build hook: [keyboard]
-> Running build hook: [keymap]
-> Running build hook: [encrypt]
==> WARNING: Possibly missing firmware for module: qat_4xxx
-> Running build hook: [filesystems]
==> Generating module dependencies
==> Creating gzip-compressed initcpio image: /boot/initramfs-5.13-x86_64.img
==> Image generation successful
==> Building image from preset: /etc/mkinitcpio.d/linux513.preset: 'fallback'
-> -k /boot/vmlinuz-5.13-x86_64 -c /etc/mkinitcpio.conf -g /boot/initramfs-5.13-x86_64-fallback.img -S autodetect
==> Starting build: 5.13.11-1-MANJARO
-> Running build hook: [base]
-> Running build hook: [udev]
-> Running build hook: [modconf]
-> Running build hook: [block]
-> Running build hook: [keyboard]
-> Running build hook: [keymap]
-> Running build hook: [encrypt]
==> WARNING: Possibly missing firmware for module: qat_4xxx
-> Running build hook: [filesystems]
==> Generating module dependencies
==> Creating gzip-compressed initcpio image: /boot/initramfs-5.13-x86_64-fallback.img
==> Image generation successful
(10/14) Refreshing PackageKit...
(11/14) Reloading system bus configuration...
(12/14) Updating icon theme caches...
(13/14) Updating the desktop file MIME type cache...
(14/14) Updating the MIME type database...
$ sudo pacman -Syu
:: Synchronising package databases...
core is up to date
extra is up to date
community is up to date
multilib is up to date
:: Starting full system upgrade...
there is nothing to do
$
After that error during initial update I see no more problems in several further updates.
And in the [Solved] Btrfs error 256 on Setup Assistant - Garuda Installer Images - Garuda Linux Forum topic it mentioned like sort of “normal error”. Does he right or wrong I do not know, but the error survived at least from that Jan 'till Aug: 7 months.