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From:   Junio C Hamano <gitster@pobox.com>
To:     Jeff King <peff@peff.net>
Cc:     Taylor Blau <me@ttaylorr.com>, git@vger.kernel.org,
        dstolee@microsoft.com
Subject: Re: [PATCH 01/10] packfile: introduce 'find_kept_pack_entry()'
References: <cover.1611098616.git.me@ttaylorr.com>
        <dc7fa4c7a61f657e779e10385d3e8076d6dac36c.1611098616.git.me@ttaylorr.com>
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        <YBRirz8xAB4Swf8X@coredump.intra.peff.net>
Date:   Fri, 29 Jan 2021 12:20:34 -0800
In-Reply-To: <YBRirz8xAB4Swf8X@coredump.intra.peff.net> (Jeff King's message
        of "Fri, 29 Jan 2021 14:31:59 -0500")
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Jeff King <peff@peff.net> writes:

> So the more compelling argument, I think, is something like:
>
>   - you sometimes want to know if object X is any kept packs
>
>   - you can't use find_pack_entry(), because it only gives you the first
>     pack it finds
>
>   - you can walk over all packs and look for the object in each.
>     pack-objects does this. But it's slow, because you are looking in
>     packs you don't care about.
>
>   - so it's helpful for the lookup to know up front which packs are
>     interesting to find objects in and which are not, to avoid looking
>     in the uninteresting ones

That does make sense.