Re: Better tarsnap usage pattern than I have?

[Colin Percival <cperciva@tarsnap.com>]

On 12/04/12 10:05, Jeff Rizzo wrote:
> Basically, I have a script on each system I'm backing up that runs tarsnap once
> a day on /, and I flag scratch partitions (etc) with 'nodump', so they don't get
> backed up.  What I'm wondering is if there's an easier/cheaper way to remove
> specific data from my daily storage totals that I later decide doesn't need
> backup without having to delete all archives between when that data was first
> backed up and when I deleted it from the master... I don't see an easy answer,
> but perhaps I'm missing something.

As far as Tarsnap usage semantics are concerned, each archive is an atomic blob
which you either keep or delete.  So no, there isn't any way to say "I want to
delete <this piece of> all these archives".

> The other thing I wonder is if there's a less bandwidth-intensive way of
> deleting stuff.  I mean, it makes sense that bandwidth is used during deletes,
> but I was a little surprised at how *much*...

How were you doing the deletes?  In particular, were you using the most recent
version of tarsnap, and were you specifying multiple -f <archivename> options to
the same invocation of tarsnap?  There's optimizations in the latest version to
reduce bandwidth usage in that case.

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