Dear maintainers, I would like to add a measurement to this old wishlist report, and ask which part of it, if any, is still considered worth pursuing.
I wrote a small script that, for a given transaction, times the download of all archives and then the sequential unpack with dpkg into a throw-away root (no root privileges, nothing installed on the host). It does not measure configure/maintainer scripts. One run on apt 3.3.3 / dpkg 1.23.11 (Kali rolling), installing libreoffice-writer with --no-install-recommends, over an ordinary home connection: packages: 51 size: 97 MB download: 262 s unpack: 7 s total: 269 s upper bound on the gain from overlapping download and unpack: 3 % So on this link the download dominates and overlapping unpack with download would save very little. This is a single run on one link; on a fast network or with packages with long maintainer scripts the picture would differ, and I can post more runs if useful. What the numbers do suggest is that, for slow links, the time is spent in the fetch phase. I would therefore like to ask: 1. Is there still interest in the original request (unpack while downloading), given that the benefit depends heavily on the link speed? 2. Would better documentation and tuning of the per-host download behaviour (Acquire::Queue-Mode, connections per host) be a more useful direction than overlapping the two phases? I am happy to send more measurements, or a patch for whichever direction you consider acceptable, as a merge request on Salsa. If you think this report should simply be closed, that is fine too. Related reports: #55044. Thanks for your time and for maintaining apt. Enzo Abyie
