[SOLVED] Does PBS make use of atime?

[IsThisThingOn]

Does PBS actually make use of atime?
Or is it just inherited because of ZFS upstream?

TrueNAS disables atime by default for performance reasons.

 

[sterzy]

Proxmox Backup Server needs at least relatime for the garbage collection to work correctly (see [1]). So yes, the atime property is needed, but for performance reasons only relatime is used (not standard atime).

From man 7 zfsprops:

 relatime=on|off
         Controls  the  manner  in  which the access time is updated when atime=on is set.  Turning this property on causes the access time to be updated relative to the
         modify or change time.  Access time is only updated if the previous access time was earlier than the current modify or change time or  if  the  existing  access
         time hasn't been updated within the past 24 hours.  The default value is on.  The values on and off are equivalent to the relatime and norelatime mount options.

[1]: https://pbs.proxmox.com/docs/maintenance.html#gc-background