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[PATCH 9/9] racy-git.txt: explain nsec problem in more detail

From
Jonathan Nieder <jrnieder@gmail.com>
Date
Oct 9, 2009, 10:25 UTC
Message-ID
<20091009102554.GI16558@progeny.tock>
In-Reply-To
<20091009101400.GA16549@progeny.tock>

Idealists may want USE_NSEC to be the default on Linux some day. Point to a patch to better explain the requirements on filesystem code for that to happen.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
---
Am I understanding the problem here correctly?  It seems to me
that ext2/3/4, tmpfs, ntfs, and so on shouldn’t have problems
with USE_NSEC, and all that is left is the monster that is
networked filesystems.
 Documentation/technical/racy-git.txt |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/Documentation/technical/racy-git.txt b/Documentation/technical/racy-git.txt
index 48bb97f..53aa0c8 100644
--- a/Documentation/technical/racy-git.txt
+++ b/Documentation/technical/racy-git.txt
@@ -42,10 +42,12 @@ compared, but this is not enabled by default because this member
 is not stable on network filesystems.  With `USE_NSEC`
 compile-time option, `st_mtim.tv_nsec` and `st_ctim.tv_nsec`
 members are also compared, but this is not enabled by default
-because the value of this member becomes meaningless once the
-inode is evicted from the inode cache on filesystems that do not
-store it on disk.
-
+because in-core timestamps can have finer granularity than
+on-disk timestamps, resulting in meaningless changes when an
+inode is evicted from the inode cache.  See commit 8ce13b0
+of git://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
+([PATCH] Sync in core time granuality with filesystems,
+2005-01-04).
 
 Racy git
 --------
-- 
1.6.5.rc1.199.g596ec
Previous: Jonathan NiederNext: Junio C Hamano
Message 17 of 19 in “Documentation tweaks”
  1. 0/9 Documentation tweaksJonathan Nieder, Oct 9, 2009
  2. 1/9 Describe DOCBOOK_XSL_172, ASCIIDOC_NO_ROFF options in MakefileJonathan Nieder, Oct 9, 2009
  3. 2/9 Documentation: git fmt-merge-message is not a scriptJonathan Nieder, Oct 9, 2009
  4. 3/9 Documentation: fix singular/plural mismatchJonathan Nieder, Oct 9, 2009
  5. 4/9 Documentation: say "the same" instead of "equal"Jonathan Nieder, Oct 9, 2009
  6. 4/9 Documentation: clarify mergeoptions descriptionJonathan Nieder, Oct 9, 2009
  7. 5/9 Documentation: clone: clarify discussion of initial branchJonathan Nieder, Oct 9, 2009
  8. Junio C HamanoOct 9, 2009
  9. 5/9 Documentation: clone: clarify discussion of initial branchJonathan Nieder, Oct 9, 2009
  10. 6/9 Documentation: branch: update --merged descriptionJonathan Nieder, Oct 9, 2009
  11. Junio C HamanoOct 10, 2009
  12. 7/9 Documentation: clarify branch creationJonathan Nieder, Oct 9, 2009
  13. Sean EstabrooksOct 9, 2009
  14. Jonathan NiederOct 9, 2009
  15. Junio C HamanoOct 10, 2009
  16. 8/9 Documentation: clarify "working tree" definitionJonathan Nieder, Oct 9, 2009
  17. 9/9 racy-git.txt: explain nsec problem in more detailJonathan Nieder, Oct 9, 2009
  18. Junio C HamanoOct 10, 2009
  19. Junio C HamanoOct 10, 2009

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