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From:   Michael Herrmann <michael@herrmann.io>
Date:   Tue, 25 Jan 2022 11:30:11 -0300
Message-ID: <CABrKpmAcNsexcmHK5kZvZr_NBm7TWWU=wVQExHwWSPpprptdQw@mail.gmail.com>
Subject: Re: A puzzle: reset --hard and hard links
To:     Andreas Schwab <schwab@linux-m68k.org>
Cc:     =?UTF-8?B?w4Z2YXIgQXJuZmrDtnLDsCBCamFybWFzb24=?= <avarab@gmail.com>,
        Junio C Hamano <gitster@pobox.com>,
        "brian m. carlson" <sandals@crustytoothpaste.net>,
        git@vger.kernel.org
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Andreas Schwab wrote:

> See the core.trustctime config.

This sounds very promising. It also fixes the problem in my
preliminary tests. Are there known drawbacks to changing this setting
to false? I haven't yet noticed a performance impact.

Randall wrote:

> I think there are more use cases here than are apparent

The use case is Chromium's build process. It creates hard links from a
src/... to a gen/... directory. Some actions do `git reset --hard` in
src/. This updates the modification time because of the hard links -
even when there are no changes. That in turn leads to unnecessary
rebuilds. I have little control over the creation of the hard links.

=C3=86var, everything you wrote is very interesting and helpful. Thank you!