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From: Junio C Hamano <gitster@pobox.com>
To: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
Cc: "Ævar Arnfjörð Bjarmason" <avarab@gmail.com>, git@vger.kernel.org
Subject: Re: The most efficient way to test if repositories share the same objects
Date: Thu, 22 Mar 2018 14:44:46 -0700	[thread overview]
Message-ID: <xmqqa7uzlr8x.fsf@gitster-ct.c.googlers.com> (raw)
In-Reply-To: <906555df-e906-775a-0255-fbc71f7138f6@linuxfoundation.org> (Konstantin Ryabitsev's message of "Thu, 22 Mar 2018 17:32:40 -0400")

Konstantin Ryabitsev <konstantin@linuxfoundation.org> writes:

> $ time git rev-list --max-parents=0 HEAD
> a101ad945113be3d7f283a181810d76897f0a0d6
> cd26f1bd6bf3c73cc5afe848677b430ab342a909
> be0e5c097fc206b863ce9fe6b3cfd6974b0110f4
> 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
>
> real    0m6.311s
> user    0m6.153s
> sys     0m0.110s
>
> If I try to do this for each of the 7700 heads, this will take roughly
> 12 hours.

Wouldn't it be more efficient to avoid doing so one-by-one?  
That is, wouldn't

	rev-list --max-parents=0 --all

be a bit faster than

	for-each-ref |
	while read object type refname
	do
		rev-list --max-parents=0 $refname
	done

I wonder?

  reply	other threads:[~2018-03-22 21:44 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-03-22 16:48 The most efficient way to test if repositories share the same objects Konstantin Ryabitsev
2018-03-22 19:20 ` Ævar Arnfjörð Bjarmason
2018-03-22 19:35   ` Junio C Hamano
2018-03-22 19:53     ` Ævar Arnfjörð Bjarmason
2018-03-22 21:32     ` Konstantin Ryabitsev
2018-03-22 21:44       ` Junio C Hamano [this message]
2018-03-23 13:57         ` Konstantin Ryabitsev
2018-03-23 14:36           ` Ævar Arnfjörð Bjarmason

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