On Wed, May 08, 2019 at 10:35:58PM +0200, Ansgar wrote: > Adam Borowski writes: > > I've recently did some research on how can we improve the speed of unpacking > > packages. There's a lot of other stages that can be improved, but let's > > talk about the .deb format. > > > > First, the 0.939 format, as described in "man deb-old". While still being > > accepted by dpkg, it had been superseded before even the very first stable > > release. Why? It has at least two upsides over 2.0: > > Switching to a different binary format will break various tools.
The 0.939 format is already supported by most tools. No one sane digs into insides of the format, using a small number of low-level tools, thus we can reuse it with little effort. Of course, adding a new compressor _does_ break compat, but we added four compressors to 2.0 over the years already, and the sky didn't fall. > If we want to do this, I wonder if we shouldn't take the chance to move > away from tar? Any seekable format significantly reduces compression, although this can be reduced by managing split points. > We have various applications that only want to extract single members of > the package (changelog, NEWS, copyright, ...); tar is a really bad > format for such an operation. Other formats (zip, 7z, ...) are more > suited for them. Perhaps such files could be considered metadata and moved to the control tarball? Or merely just moved forward -- remember that tarballs are unordered. Meow! -- ⢀⣴⠾⠻⢶⣦⠀ ⣾⠁⢰⠒⠀⣿⡁ ⢿⡄⠘⠷⠚⠋⠀ NADIE anticipa la inquisición de españa! ⠈⠳⣄⠀⠀⠀⠀
