On Thu, Sep 7, 2017 at 11:55 AM, Garance AE Drosehn <[email protected]> wrote: > >> On Sep 7, 2017, at 4:21 AM, [email protected] wrote: >> >>> So, can I make it smaller than 1.07 GB? Am I doing something wrong? I can >>> explain what kind data are part of those 1.45 GB (can give a breakup too >>> if needed). >>> >>> Can I compress it more, make de-duplication more aggressive? I have used >>> the default config that came with the app. >> >> Or should I ask it in a separate thread? Or rather shoot a mail to Tarsnap >> support? (But I see Graham is CCed in this mail thread). >> >> Thanks. > > There is one thing to note about de-duplication in tarsnap, compared to some > other services. Tarsnap can only de-duplicate across the files *you* are > backing up, on a single specific machine you are backing up. This is a > side-effect of all the privacy and encryption that tarsnap guarantees. > > De-duplication works great in some other situations because the other service > is de-duplicating files across (say) 20 different Windows machines. So the > first machine may use up 10-gig of space, but all of the rest of the machines > might have less than a gig of additional unique files per machine. Tarsnap > cannot do that kind of optimization across multiple machines.
Depending on just how paranoid you are, and how disciplined you are, you can have multiple machines deduplicate to a common store, as long as you only have one running at a time. What you wrote does not preclude that from happening, I just wanted to point it out in case others might be interested in something like that. -- Scott Robison
