Hi! On Mon, 2023-07-03 at 21:37:08 +0200, Sebastian Andrzej Siewior wrote: > This started in 2021 and I have no idea what to do with it so here it > is. Let me get back to how it started: > I was looking into the why does it take some time after apt downloaded > the packages before dpkg starts installing them. As it turns out, I had > apt-listchanges installed which decompresses all .deb files looking for > "NEWS". That was the pause. Then dpkg decompresses it again while > installing. So a bit of waste…
Yes. > Now on the serious side: > - Does this look usefull? While I think the current situation is not ideal, I find hardcoding pathname assumptions into the dpkg-deb or dpkg to be non-starters. This additionally would mean the output from for example «dpkg -L» is not "sorted" anymore, and dpkg can currently not sort it further from its side because it needs to preserve the property of listing symlinks last (which your patch does, but regresses on the non-symlink cases). Sorting this from the dpkg side would be possible once it has fsys metadata tracking information. How to select which files to put first could perhaps be done with the old proposal for pathname classes (so that the "policy" is in the packager hands and not on the tooling), but even then placing them at the beginning of the data.tar, still seems like a hack. > - Any suggestion to how to speed apt-listchanges? A special interface or > better remove the package? I think the better option would be to ship these files as part of the control.tar member, see for example: https://lists.debian.org/debian-devel/2012/07/msg00398.html which contains further references. Although AFAIR last time this was brought up there was no support for this at least in Debian. I've not tried to implement or improve support for this in dpkg, because if this ends up not being used there, then it would become a rather confusing interface. But perhaps there's some way to move the needle in that direction w/o making this confusing or forcing Debian's hand as a fait accompli kind of thing. Thanks, Guillem
