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From: "Derrick Stolee via GitGitGadget" <gitgitgadget@gmail.com>
To: git@vger.kernel.org
Cc: jonathantanmy@google.com, Junio C Hamano <gitster@pobox.com>
Subject: [PATCH 0/1] sha1-file: split OBJECT_INFO_FOR_PREFETCH
Date: Tue, 28 May 2019 08:19:06 -0700 (PDT)	[thread overview]
Message-ID: <pull.228.git.gitgitgadget@gmail.com> (raw)

I found this interaction while testing the VFS for Git fork rebasing onto
v2.22.0-rc1 [1]. It seems this new flag meant for partial clone prefetches
interacts poorly with the read-object hook we use in our fork.

The issue is that OBJECT_INFO_FOR_PREFETCH has multiple bits on, so testing
"flag & OBJECT_INFO_FOR_PREFETCH" can be true even if not all bits are on.
My fix simply splits the new bit into a special flag while keeping
OBJECT_INFO_FOR_PREFETCH as a union of flags.

Jury is out if this fixes our problem, but it definitely seems like a bug
waiting to happen in Git, too.

Thanks, -Stolee

[1] https://github.com/microsoft/git/pull/140

Derrick Stolee (1):
  sha1-file: split OBJECT_INFO_FOR_PREFETCH

 object-store.h | 10 +++++++---
 sha1-file.c    |  2 +-
 2 files changed, 8 insertions(+), 4 deletions(-)


base-commit: 0f4a4fb1c4239a2aa46343add84ad6f99f6f3aae
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-228%2Fderrickstolee%2Fobject-info-prefetch-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-228/derrickstolee/object-info-prefetch-v1
Pull-Request: https://github.com/gitgitgadget/git/pull/228
-- 
gitgitgadget

             reply	other threads:[~2019-05-28 15:19 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-28 15:19 Derrick Stolee via GitGitGadget [this message]
2019-05-28 15:19 ` [PATCH 1/1] sha1-file: split OBJECT_INFO_FOR_PREFETCH Derrick Stolee via GitGitGadget
2019-05-28 20:31   ` Junio C Hamano
2019-05-28 20:54   ` Jeff King
2019-05-29  0:29     ` Derrick Stolee

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