[Gnu-arch-users] hardlinked pristine trees

[Pau Aliagas]

I'm thinking about adding another optional optimization to arch that would 
consist of hardlinking pristine trees to revision libraries, the same that 
I've done for get and build-config.

I agree with some of the expressed complaints that working with hard links 
is inherently dangerous... in working directories. Of course if you choose 
this way it's up to to to be careful til some validation code is added to 
cached revisions (it'll come some day).

But (and that's a big but), I don't see any danger in hardlinking pristine
trees. The danger is the same than if you corrupt a local pristine, be it
hardlinked or not, but the benefits are obvious: space saving, full speed
gets, etc. Pristine trees are neeed, for instance, to compute
what-changed.

There are quite a bunch of files to modify:

archive-cache.c build-revision.c cmd-add-pristine.c cmd-buildcfg.c
cmd-cachedrevs.c cmd-cacherev.c cmd-deltapatch.c cmd-find-pristine.c
cmd-getrev.c cmd-join-branch.c cmd-lock-pristine.c cmd-ls-pristines.c
cmd-replay.c cmd-revdelta.c cmds.c cmd-uncacherev.c cmd-undo-changes.c
cmd-what-changed.c commit.c configs.c import.c local-cache.c pristines.c
tag.c)

so that I won't undertake it unless there's some consensus about it and 
some hope to get it integrated in mainstream. I'm really busy now :/

Does anybody have an opinion about it?

Pau