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From: Junio C Hamano <gitster@pobox.com>
To: Jeff King <peff@peff.net>
Cc: Matt McCutchen <matt@mattmccutchen.net>, git <git@vger.kernel.org>
Subject: Re: Protecting old temporary objects being reused from concurrent "git gc"?
Date: Wed, 16 Nov 2016 10:58:30 -0800	[thread overview]
Message-ID: <xmqq1sybqmjt.fsf@gitster.mtv.corp.google.com> (raw)
In-Reply-To: <20161115174028.zvohfcw4jse3jrmm@sigill.intra.peff.net> (Jeff King's message of "Tue, 15 Nov 2016 12:40:29 -0500")

Jeff King <peff@peff.net> writes:

> I suspect the issue is that read-tree populates the cache-tree index
> extension, and then write-tree omits the object write before it even
> gets to write_sha1_file().

Wait a minute.  The entries in the index and trees in the cache-tree
are root of "still in use" traversal for the purpose of pruning,
which makes the "something like this" patch unnecessary for the real
index file.

And for temporary index files that is kept for 6 months, touching
tree objects that cache-tree references is irrelevant---the blobs
recorded in the "list of objects" part of the index will go stale,
which is a lot more problematic.

  parent reply	other threads:[~2016-11-16 18:58 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-11-15 14:13 Protecting old temporary objects being reused from concurrent "git gc"? Matt McCutchen
2016-11-15 17:06 ` Jeff King
2016-11-15 17:33   ` Matt McCutchen
2016-11-15 17:40     ` Jeff King
2016-11-15 19:08       ` [PATCH] git-gc.txt: expand discussion of races with other processes Matt McCutchen
2016-11-15 19:12       ` Protecting old temporary objects being reused from concurrent "git gc"? Matt McCutchen
2016-11-15 20:01       ` Junio C Hamano
2016-11-16  8:07         ` Jeff King
2016-11-16 18:18           ` Junio C Hamano
2016-11-16 18:58       ` Junio C Hamano [this message]
2016-11-17  1:04         ` Jeff King
2016-11-17  1:35           ` Re* " Junio C Hamano
2016-11-17  1:43             ` Jeff King

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