Hi! On Thu, 2018-11-15 at 00:37:10 -0500, Rémi Rampin wrote: > Upstream developer here. ReproZip needs to match from filename to package, > not the other way around. It formerly used `dpkg-query -S FILENAME` to do > this, but this was switched to reading the database directly for > performance reasons (exact commit is > https://github.com/ViDA-NYU/reprozip/commit/b085c41035959a451d77b0defa8c8b4ba025f47e). > When many files need to be looked up, it is more efficient to do a single > read through the info/*.list files than to do many such queries.
Ah right sorry, read that code sideways. > If I am missing a fast way to do this using the correct external interface, > please let me know, and I will gladly update the code. The same principle I proposed for --listfiles can be used for --search, you'd just batch as many filenames as can possibly fit within the command-line length limit (ARG_MAX - environment length) to reduce as many dpkg-query calls as possible. Doing a «dpkg-query --search» call per filename will indeed end up being very expensive. Thanks, Guillem
