Re: [PATCH] Add core.trustlowlevelstat for diffs in dev,ino,uid and gid

From: Junio C Hamano <gitster@pobox.com>
Date: Apr 27, 2009, 06:55 UTC
Message-ID: <7vab628u23.fsf@gitster.siamese.dyndns.org>
In-Reply-To: <alpine.LFD.2.00.0904261159190.7331@localhost.localdomain>

Linus Torvalds <torvalds@linux-foundation.org> writes:

> I started out wanting to check the stat information as much as possible, 
> but realistically, nobody probably really cares. We already effectively 
> removed st_dev checking and nsec checks.

Was ignoring st_dev checking primarily for a work tree over NFS? I think ignoring it makes sense. If st_dev changes, it is likely that somebody did a "mv" of a whole repository to some other filesystem, or the filesystem is not giving stable st_dev to us for the whole tree---it is not like we want to detect a change to a single path that changes its st_dev and nothing else, as no such change is likely to be useful.

> IOW, maybe we should just do this, and remove over a hundred lines of dead 
> code or commentary/config. And never have to worry about these kinds of 
> issues with different environments again.

I like the end result.

But I am not sure about dropping the nanosecond resolution timestamps. The area was extended recently in preparation for ext4; we can take advantage of it to reduce the chance the racy-git avoidance codepath triggers if we keep it.

    fba2f38 (make USE_NSEC work as expected, 2009-02-19)

    c06ff49 (Record ns-timestamps if possible, but do not use it without
    USE_NSEC, 2009-03-04)