Re: [Gnu-arch-users] archive storage format comments on the size

[Andrea Arcangeli]

On Mon, Sep 29, 2003 at 05:03:09PM -0700, David Brown wrote:
> On Tue, Sep 30, 2003 at 01:30:26AM +0200, Andrea Arcangeli wrote:
> 
> > > IIRC, tar pads out its files to end on a 10k boundary, and has internal
> > > padding such that even a 1-byte files takes about 1k to store. Hence, I
> > > wouldn't quite go as far to say "no waste of space due to the fs" -- as
> > > long as you're willing to consider the tar format a filesystem for those
> > > purposes.
> > 
> > I never notice the 1k alignment of files in tar in practice, sounds
> > like if they didn't want to store a 64bit for defining the i_size but I
> > never looked into the tar sources so I'm just guessing. Ironically some
> > fs does a better compacting job than tar. About the 10k boundary, that
> > one doesn't matter at all is a >65M file.
> 
> The tar header is 512 bytes, unless the name is very long.  The data is
> written in units of 512 bytes, so the minimum there is 512.
> 
> The 10k boundary padding is before compression.

then it's the half the overhead, doesn't make that much difference
either ways.

Andrea - If you prefer relying on open source software, check these links:
            rsync.kernel.org::pub/scm/linux/kernel/bkcvs/linux-2.[45]/
            http://www.cobite.com/cvsps/