git/contrib
Neeraj Singh abf38abec2 core.fsyncmethod: add writeout-only mode
This commit introduces the `core.fsyncMethod` configuration
knob, which can currently be set to `fsync` or `writeout-only`.

The new writeout-only mode attempts to tell the operating system to
flush its in-memory page cache to the storage hardware without issuing a
CACHE_FLUSH command to the storage controller.

Writeout-only fsync is significantly faster than a vanilla fsync on
common hardware, since data is written to a disk-side cache rather than
all the way to a durable medium. Later changes in this patch series will
take advantage of this primitive to implement batching of hardware
flushes.

When git_fsync is called with FSYNC_WRITEOUT_ONLY, it may fail and the
caller is expected to do an ordinary fsync as needed.

On Apple platforms, the fsync system call does not issue a CACHE_FLUSH
directive to the storage controller. This change updates fsync to do
fcntl(F_FULLFSYNC) to make fsync actually durable. We maintain parity
with existing behavior on Apple platforms by setting the default value
of the new core.fsyncMethod option.

Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-10 15:10:22 -08:00
..
buildsystems core.fsyncmethod: add writeout-only mode 2022-03-10 15:10:22 -08:00
coccinelle index-pack: use xopen in init_thread 2021-09-10 14:22:50 -07:00
completion Merge branch 'ab/complete-show-all-commands' 2022-02-17 16:25:06 -08:00
contacts git-contacts: also recognise "Reported-by:" 2017-07-27 09:42:55 -07:00
credential *.[ch] *_INIT macros: use { 0 } for a "zero out" idiom 2021-09-27 14:47:59 -07:00
diff-highlight diff-highlight: correctly match blank lines for flush 2020-09-21 22:33:28 -07:00
emacs git{,-blame}.el: remove old bitrotting Emacs code 2018-04-16 17:25:49 +09:00
examples Merge branch 'bw/c-plus-plus' into ds/lazy-load-trees 2018-04-11 10:46:32 +09:00
fast-import import-tars: ignore the global PAX header 2020-03-24 14:39:47 -07:00
git-jump git-jump: pass "merge" arguments to ls-files 2021-11-09 11:15:21 -08:00
git-shell-commands
hg-to-git hg-to-git: make it compatible with both python3 and python2 2019-09-18 12:03:05 -07:00
hooks multimail: stop shipping a copy 2021-06-11 13:35:19 +09:00
long-running-filter docs: warn about possible '=' in clean/smudge filter process values 2016-12-06 11:29:52 -08:00
mw-to-git t6000-t9999: detect and signal failure within loop 2021-12-13 10:29:48 -08:00
persistent-https docs/config: mention protocol implications of url.insteadOf 2017-06-01 10:07:10 +09:00
remote-helpers contrib: git-remote-{bzr,hg} placeholders don't need Python 2017-03-03 11:09:34 -08:00
scalar scalar: accept -C and -c options before the subcommand 2022-01-28 15:14:38 -08:00
stats contrib: update stats/mailmap script 2012-12-12 11:09:11 -08:00
subtree subtree: force merge commit 2022-02-01 11:31:51 -08:00
thunderbird-patch-inline contrib/thunderbird-patch-inline/appp.sh: use the $( ... ) construct for command substitution 2015-12-27 15:33:13 -08:00
update-unicode unicode_width.h: rename to use dash in file name 2018-04-11 18:11:00 +09:00
vscode vscode: let cSpell work on commit messages, too 2018-07-30 13:14:39 -07:00
workdir git-new-workdir: mark script as LF-only 2017-05-10 13:32:50 +09:00
coverage-diff.sh contrib: add coverage-diff script 2018-10-10 10:11:35 +09:00
git-resurrect.sh contrib/git-resurrect.sh: use hash-agnostic OID pattern 2020-10-08 11:48:56 -07:00
README
remotes2config.sh
rerere-train.sh rerere-train: two fixes to the use of "git show -s" 2022-02-27 14:14:03 -08:00

Contributed Software

Although these pieces are available as part of the official git
source tree, they are in somewhat different status.  The
intention is to keep interesting tools around git here, maybe
even experimental ones, to give users an easier access to them,
and to give tools wider exposure, so that they can be improved
faster.

I am not expecting to touch these myself that much.  As far as
my day-to-day operation is concerned, these subdirectories are
owned by their respective primary authors.  I am willing to help
if users of these components and the contrib/ subtree "owners"
have technical/design issues to resolve, but the initiative to
fix and/or enhance things _must_ be on the side of the subtree
owners.  IOW, I won't be actively looking for bugs and rooms for
enhancements in them as the git maintainer -- I may only do so
just as one of the users when I want to scratch my own itch.  If
you have patches to things in contrib/ area, the patch should be
first sent to the primary author, and then the primary author
should ack and forward it to me (git pull request is nicer).
This is the same way as how I have been treating gitk, and to a
lesser degree various foreign SCM interfaces, so you know the
drill.

I expect that things that start their life in the contrib/ area
to graduate out of contrib/ once they mature, either by becoming
projects on their own, or moving to the toplevel directory.  On
the other hand, I expect I'll be proposing removal of disused
and inactive ones from time to time.

If you have new things to add to this area, please first propose
it on the git mailing list, and after a list discussion proves
there are some general interests (it does not have to be a
list-wide consensus for a tool targeted to a relatively narrow
audience -- for example I do not work with projects whose
upstream is svn, so I have no use for git-svn myself, but it is
of general interest for people who need to interoperate with SVN
repositories in a way git-svn works better than git-svnimport),
submit a patch to create a subdirectory of contrib/ and put your
stuff there.

-jc