Re: Using the --snaptime option

[Colin Percival <cperciva@tarsnap.com>]

On 01/23/14 08:56, Daniel Staal wrote:
> --As of January 23, 2014 8:32:14 AM -0800, Colin Percival is alleged to have said:
>> That will effectively disable the "recognize when files haven't changed"
>> functionality, which will force Tarsnap to re-read files which it might
>> otherwise have not bothered to re-read.
> 
> So, essentially for this purpose it's the same as the `--newer-than` option, and
> could be replaced with any of the --newer options, right?

No, not at all.  As Albert said, it's more of a --assume-modified-if-newer-than
option (although "--assume-potentially-modified-if-newer-than" would be closer).

> (Of course, we are talking about ZFS snapshots here, which is already have an
> atomic creation and can be browsed like any other filesystem.  I'm not sure if
> that applies to other forms of snapshots.)

Atomic creation doesn't solve the problem of timestamps being too coarse grained
to distinguish between a time just before and a time just after the snapshot was
created.

-- 
Colin Percival
Security Officer Emeritus, FreeBSD | The power to serve
Founder, Tarsnap | www.tarsnap.com | Online backups for the truly paranoid