On Wed, Apr 25, 2018 at 5:18 PM, Marc Branchaud <marcnarc@xxxxxxxxxxx> wrote: > Are we all that sure that the performance hit is that drastic? After all, > we've just done write_entry(). Calling utime() at that point should just > hit the filesystem cache. I have a feeling this has "this is linux" assumption. Anybody knows how freebsd, mac os x and windows behave? > The post-checkout hook approach is not exactly straightforward. > > Naively, it's simply > > for F in `git diff --name-only $1 $2`; do touch "$F"; done > > But consider: > > * Symlinks can cause the wrong file to be touched. (Granted, Michał's > proposed patch also doesn't deal with symlinks.) Let's assume that a hook > can be crafted will all possible sophistication. There are still some > fundamental problems: > > * In a "file checkout" ("git checkout -- path/to/file"), $1 and $2 are > identical so the above loop does nothing. Offhand I'm not even sure how a > hook might get the right files in this case. Would a hook that gives you the list of updated files (in the exact same order that git updates) help? > * The hook has to be set up in every repo and submodule (at least until > something like Ævar's experiments come to fruition). > > * A fresh clone can't run the hook. This is especially important when > dealing with submodules. (In one case where we were bit by this, make > though that half of a fresh submodule clone's files were stale, and decided > to re-autoconf the entire thing.) This to me sounds like something we should be able to improve in general. The alternative is "git clone --no-checkout" then checkout manually (which I see jenkins plugin does) is really not optimal even if it works. -- Duy