Hello list, I have been investigating the slow performance of pacman regarding the cold caches scenario and I'm trying to write some proof of concept code that improves things a lot for some cases. However I need your help regarding some facts I might have misunderstood, and any pointers to the source code you also give me would also help a lot. I wouldn't like to lose time changing stuff that would break current functionality. So here are some first questions that come to mind, just by using strace: When doing "pacman -Q blah" I can see that besides the getdents() syscalls in /var/lib/pacman/local (probably caused by readdir()), there are also stat() and access() calls for every single subdirectory. Why are the last ones necessary? Isn't readdir enough? The same goes when doing "pacman -S blah". But in that case it stat()'s both 'local' and 'sync' directories, so worst case is really bad, it will stat() all contents of local, core, extra and community... In the case of "pacman -S" I measured that a great deal of time goes also to reading the "depends" files of all packages in local, please enlighten me what this is for. I have thought of a new way to store dependencies that should improve things, but I should first be sure it doesn't break anything and get some measurements myself. Thanks in advance, Dimitris P.S. Is there some option --pretend I might have missed? What I need is to get exactly the same actions of "pacman -S blah" or "pacman -Su" until the Y/N prompt, as non-root user.