On 2020-06-16 03:36:22 [+0200], Guillem Jover wrote: > Hi! Hi, > > I've been thinking about parallel decompression for dpkg/xz. Is there > > any interest in doing this? I hacked parallel-unxz [0] in the meantime > > to see what is missing from the API point of view (query block offsets > > is missing). > > I'm interested, but mainly if this is provided transparently by > liblzma, in a similar way as it is currently provided for compression.
I dropped that idea because it was very complex. > > My idea of accomplishing this is roughly the following: > > During archive creation the output of tar is also analysed (like via > > libarchive) in order to gain the start position of the files within the > > uncompressed archive (which is something pixz does). > > When I checked the implementation in pixz it looked not very efficient > in terms of memory, AFAIR. … > The biggest issue is that the dpkg codebase is very much not > thread-safe, so implementing this would imply either duplicating much > of the existing infrastructure, such as using different error handling > stuff, or to bolt this on top, which seems rather unappealing. > > I've seen the discussion in the upstream list, and I'd really like to > get this supported there, also because it would benefit many other > projects. :) Oki. I started looking into this but other things popped up. Lets see… > Thanks, > Guillem Sebastian
