Determine the creation time of a root tree

Determine the creation time of a root tree

[Ivan Sizov]

Is there a way to know when the root tree or generation was created?
btrfs-find-root doesn't have such option.

--
Ivan Sizov (SIvan)

Re: Determine the creation time of a root tree

[Hugo Mills]

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On Sat, Aug 06, 2016 at 06:11:58PM +0300, Ivan Sizov wrote:
> Is there a way to know when the root tree or generation was created?
> btrfs-find-root doesn't have such option.

   In UTC (or similar wall-clock-like units)? Not easily.

   I think you'd have to do something like look at the modification
time of a file, and then find the latest generation of any item
associated with that file, which would give you a time/inode pairing.
Do enough of those, and you'd have some kind of map that you could use
to approximate the time for a given genid.

   Hugo.

-- 
Hugo Mills             | This year, I'm giving up Lent.
hugo@... carfax.org.uk |
http://carfax.org.uk/  |
PGP: E2AB1DE4          |

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Re: Determine the creation time of a root tree

[David Sterba]

On Sat, Aug 06, 2016 at 06:11:58PM +0300, Ivan Sizov wrote:
> Is there a way to know when the root tree or generation was created?
> btrfs-find-root doesn't have such option.

The 'otime' is set and stored witin the inode item that represents the
subvolume. At the moment there's no direct way to read the otime for
topelvel subvolume, otherwise it's available via
'btrfs subvolume show /path/subvolume'