Incorrect ZFS file system 'atime' property in zpool
Despite having set the
atime property to
off for the root pool, several file systems are mounted with
atime=on from initramfs (container names are redacted):
# zfs get -r atime NAME PROPERTY VALUE SOURCE rpool atime off local rpool/ROOT atime off inherited from rpool rpool/ROOT/alpine atime on temporary rpool/home atime on temporary rpool/lxc atime on temporary rpool/lxc/<c1> atime off inherited from rpool rpool/lxc/<c2> atime off inherited from rpool rpool/srv atime on temporary rpool/var atime on temporary #
This is not how ZFS should work, importing the root pool should honour this setting, as it does on Solaris and FreeBSD.
I guess this is not necessarily Alpine related, but a more generic Linux problem because of how Linux boots with initramfs, then does a pivot_root. Though Solaris (and derivatives) works similarly with its boot archive. Issue #8609 looks related: the resolution there seemed to cause this.
I tried a workaround by adding
/etc/update-extlinux.conf, then ran
update-extlinux and reboot, but it did not help. Maybe I'm missing a point.
Edit, addition on 11.2.2021:
It seems like it affects non-root zpools, too. I've reinstalled the server meanwhile (for other reasons, out of scope) and here's what I can see currently (
redact.sh just replaces the poolname):
zfs list -t all -r | ./redact.sh NAME USED AVAIL REFER MOUNTPOINT linux_sda4 4.59M 221G 96K /linux_sda4 linux_sda4/home 124K 221G 124K /home linux_sda4/srv 96K 221G 96K /srv linux_sda4/var 2.11M 221G 2.11M /var # zfs get -r mountpoint,atime,canmount,mounted | ./redact.sh NAME PROPERTY VALUE SOURCE linux_sda4 mountpoint /linux_sda4 default linux_sda4 atime off local linux_sda4 canmount noauto local linux_sda4 mounted no - linux_sda4/home mountpoint /home local linux_sda4/home atime on temporary linux_sda4/home canmount on default linux_sda4/home mounted yes - linux_sda4/srv mountpoint /srv local linux_sda4/srv atime on temporary linux_sda4/srv canmount on default linux_sda4/srv mounted yes - linux_sda4/var mountpoint /var local linux_sda4/var atime on temporary linux_sda4/var canmount on default linux_sda4/var mounted yes - # mount | grep zfs | ./redact.sh linux_sda4/var on /var type zfs (rw,noatime,xattr,noacl) linux_sda4/srv on /srv type zfs (rw,noatime,xattr,noacl) linux_sda4/home on /home type zfs (rw,noatime,xattr,noacl) #
- no matter if I set
atime=offfor the whole pool, the mountpoints do not inherit this
- the output of
mountare contradicting each other: