When adding many objects to a repo with `core.fsync=loose-object`,
the cost of fsync'ing each object file can become prohibitive.
One major source of the cost of fsync is the implied flush of the
hardware writeback cache within the disk drive. This commit introduces
a new `core.fsyncMethod=batch` option that batches up hardware flushes.
It hooks into the bulk-checkin odb-transaction functionality, takes
advantage of tmp-objdir, and uses the writeout-only support code.
When the new mode is enabled, we do the following for each new object:
1a. Create the object in a tmp-objdir.
2a. Issue a pagecache writeback request and wait for it to complete.
At the end of the entire transaction when unplugging bulk checkin:
1b. Issue an fsync against a dummy file to flush the log and hardware
writeback cache, which should by now have seen the tmp-objdir writes.
2b. Rename all of the tmp-objdir files to their final names.
3b. When updating the index and/or refs, we assume that Git will issue
another fsync internal to that operation. This is not the default
today, but the user now has the option of syncing the index and there
is a separate patch series to implement syncing of refs.
On a filesystem with a singular journal that is updated during name
operations (e.g. create, link, rename, etc), such as NTFS, HFS+, or XFS
we would expect the fsync to trigger a journal writeout so that this
sequence is enough to ensure that the user's data is durable by the time
the git command returns. This sequence also ensures that no object files
appear in the main object store unless they are fsync-durable.
Batch mode is only enabled if core.fsync includes loose-objects. If
the legacy core.fsyncObjectFiles setting is enabled, but core.fsync does
not include loose-objects, we will use file-by-file fsyncing.
In step (1a) of the sequence, the tmp-objdir is created lazily to avoid
work if no loose objects are ever added to the ODB. We use a tmp-objdir
to maintain the invariant that no loose-objects are visible in the main
ODB unless they are properly fsync-durable. This is important since
future ODB operations that try to create an object with specific
contents will silently drop the new data if an object with the target
hash exists without checking that the loose-object contents match the
hash. Only a full git-fsck would restore the ODB to a functional state
where dataloss doesn't occur.
In step (1b) of the sequence, we issue a fsync against a dummy file
created specifically for the purpose. This method has a little higher
cost than using one of the input object files, but makes adding new
callers of this mechanism easier, since we don't need to figure out
which object file is "last" or risk sharing violations by caching the fd
of the last object file.
_Performance numbers_:
Linux - Hyper-V VM running Kernel 5.11 (Ubuntu 20.04) on a fast SSD.
Mac - macOS 11.5.1 running on a Mac mini on a 1TB Apple SSD.
Windows - Same host as Linux, a preview version of Windows 11.
Adding 500 files to the repo with 'git add' Times reported in seconds.
object file syncing | Linux | Mac | Windows
--------------------|-------|-------|--------
disabled | 0.06 | 0.35 | 0.61
fsync | 1.88 | 11.18 | 2.47
batch | 0.15 | 0.41 | 1.53
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Make it clearer in the naming and documentation of the plug_bulk_checkin
and unplug_bulk_checkin APIs that they can be thought of as
a "transaction" to optimize operations on the object database. These
transactions may be nested so that subsystems like the cache-tree
writing code can optimize their operations without caring whether the
top-level code has a transaction active.
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit prepares for adding batch-fsync to the bulk-checkin
infrastructure.
The bulk-checkin infrastructure is currently used to batch up addition
of large blobs to a packfile. When a blob is larger than
big_file_threshold, we unconditionally add it to a pack. If bulk
checkins are 'plugged', we allow multiple large blobs to be added to a
single pack until we reach the packfile size limit; otherwise, we simply
make a new packfile for each large blob. The 'unplug' call tells us when
the series of blob additions is done so that we can finish the packfiles
and make their objects available to subsequent operations.
Stated another way, bulk-checkin allows callers to define a transaction
that adds multiple objects to the object database, where the object
database can optimize its internal operations within the transaction
boundary.
Batched fsync will fit into bulk-checkin by taking advantage of the
plug/unplug functionality to determine the appropriate time to fsync
and make newly-added objects available in the primary object database.
* Rename 'state' variable to 'bulk_checkin_state', since we will later
be adding 'bulk_fsync_objdir'. This also makes the variable easier to
find in the debugger, since the name is more unique.
* Move the 'plugged' data member of 'bulk_checkin_state' into a separate
static variable. Doing this avoids resetting the variable in
finish_bulk_checkin when zeroing the 'bulk_checkin_state'. As-is, we
seem to unintentionally disable the plugging functionality the first
time a new packfile must be created due to packfile size limits. While
disabling the plugging state only results in suboptimal behavior for
the current code, it would be fatal for the bulk-fsync functionality
later in this patch series.
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
PowerShell does not understand the Command Prompt `%ENV_VAR%` syntax, it
uses `$env:ENV_VAR` instead. Offer such an invocation to the reader in
the "What options did you set as part of the installation" question.
Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Get rid of a bogus and over-eager coccinelle rule.
source: <xmqq1qxd6e4x.fsf@gitster.g>
* jc/cocci-xstrdup-or-null-fix:
cocci: drop bogus xstrdup_or_null() rule
"git format-patch <args> -- <pathspec>" lost the pathspec when
showing the second and subsequent commits, which has been
corrected.
source: <c36896a1-6247-123b-4fa3-b7eb24af1897@web.de>
* rs/format-patch-pathspec-fix:
2.36 format-patch regression fix
"git fast-export -- <pathspec>" lost the pathspec when showing the
second and subsequent commits, which has been corrected.
source: <2c988c7b-0efe-4222-4a43-8124fe1a9da6@web.de>
* rs/fast-export-pathspec-fix:
2.36 fast-export regression fix
"git show <commit1> <commit2>... -- <pathspec>" lost the pathspec
when showing the second and subsequent commits, which has been
corrected.
source: <xmqqo80j87g0.fsf_-_@gitster.g>
* jc/show-pathspec-fix:
2.36 show regression fix
Regression fix for 2.36 where "git name-rev" started to sometimes
reference strings after they are freed.
This fixes a regression in 2.36 and is slate to go to 2.36.1
source: <340c8810-d912-7b18-d46e-a9d43f20216a@web.de>
* rs/name-rev-fix-free-after-use:
Revert "name-rev: release unused name strings"
"diff-tree --stdin" has been broken for about a year, but 2.36
release broke it even worse by breaking running the command with
<pathspec>, which in turn broke "gitk" and got noticed. This has
been corrected by aligning its behaviour to that of "log".
This fixes a regression in 2.36 and is slate to go to 2.36.1
source: <xmqq7d7bsu2n.fsf@gitster.g>
* jc/diff-tree-stdin-fix:
2.36 gitk/diff-tree --stdin regression fix
"git submodule update" without pathspec should silently skip an
uninitialized submodule, but it started to become noisy by mistake.
This fixes a regression in 2.36 and is slate to go to 2.36.1
source: <pull.1258.v2.git.git.1650890741430.gitgitgadget@gmail.com>
* gc/submodule-update-part2:
submodule--helper: fix initialization of warn_if_uninitialized
13092a91 (cocci: refactor common patterns to use xstrdup_or_null(),
2016-10-12) introduced a rule to rewrite this conditional call to
xstrdup(E) and an assignment to variable V:
- if (E)
- V = xstrdup(E);
into an unconditional call to xstrdup_or_null(E) and an assignment
to variable V:
+ V = xstrdup_or_null(E);
which is utterly bogus. The original code may already have an
acceptable value in V and the conditional assignment may be to
improve the value already in V with a copy of a better value E when
(and only when) E is not NULL.
The rewritten construct unconditionally discards the existing value
of V and replaces it with a copy of E, even when E is NULL, which
changes the meaning of the program.
By the way, if it were
-if (E && !V)
- V = xstrdup(E);
+V = xstrdup_or_null(E);
it would probably have been correct. But there is no existing code
that would have been improved by such a rule, so let's just remove
the bogus one without replacing with the more specific one.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
e900d494dc (diff: add an API for deferred freeing, 2021-02-11) added a
way to allow reusing diffopts: the no_free bit. 244c27242f (diff.[ch]:
have diff_free() call clear_pathspec(opts.pathspec), 2022-02-16) made
that mechanism mandatory.
git fast-export doesn't set no_free, so path limiting stopped working
after the first commit. Set the flag and add a basic test to make sure
only changes to the specified files are exported.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
e900d494dc (diff: add an API for deferred freeing, 2021-02-11) added a
way to allow reusing diffopts: the no_free bit. 244c27242f (diff.[ch]:
have diff_free() call clear_pathspec(opts.pathspec), 2022-02-16) made
that mechanism mandatory.
git format-patch only sets no_free when --output is given, causing it to
forget pathspecs after the first commit. Set no_free unconditionally
instead.
The existing test was unable to detect this breakage because it checks
stderr for the absence of a certain string, but format-patch writes to
stdout. Also the test was not checking the case of one commit modifying
multiple files and a pathspec limiting the diff. Replace it with a more
thorough one.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This only surfaced as a regression after 2.36 release, but the
breakage was already there with us for at least a year.
e900d494 (diff: add an API for deferred freeing, 2021-02-11)
introduced a mechanism to delay freeing resources held in
diff_options struct that need to be kept as long as the struct will
be reused to compute diff. "git log -p" was taught to utilize the
mechanism but it was done with an incorrect assumption that the
underlying helper function, cmd_log_walk(), is called only once,
and it is OK to do the freeing at the end of it.
Alas, for "git show A B", the function is called once for each
commit given, so it is not OK to free the resources until we finish
calling it for all the commits given from the command line.
During 2.36 release cycle, we started clearing the <pathspec> as
part of this freeing, which made the bug a lot more visible.
Fix this breakage by tweaking how cmd_log_walk() frees the resources
at the end and using a variant of it that does not immediately free
the resources to show each commit object from the command line in
"git show".
Protect the fix with a few new tests.
Reported-by: Daniel Li <dan@danielyli.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The phrasing confused some users to believe that the built-in FSMonitor
was deprecated altogether. Let's try to clear that up.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The .warn_if_uninitialized member was introduced by 48308681
(git submodule update: have a dedicated helper for cloning,
2016-02-29) to submodule_update_clone struct and initialized to
false. When c9911c93 (submodule--helper: teach update_data more
options, 2022-03-15) moved it to update_data struct, it started
to initialize it to true but this change was not explained in
its log message.
The member is set to true only when pathspec was given, and is
used when a submodule that matched the pathspec is found
uninitialized to give diagnostic message. "submodule update"
without pathspec is supposed to iterate over all submodules
(i.e. without pathspec limitation) and update only the
initialized submodules, and finding uninitialized submodules
during the iteration is a totally expected and normal thing that
should not be warned.
[jc: added tests]
Signed-off-by: Orgad Shaneh <orgads@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This only surfaced as a regression after 2.36 release, but the
breakage was already there with us for at least a year.
The diff_free() call is to be used after we completely finished with
a diffopt structure. After "git diff A B" finishes producing
output, calling it before process exit is fine. But there are
commands that prepares diff_options struct once, compares two sets
of paths, releases resources that were used to do the comparison,
then reuses the same diff_option struct to go on to compare the next
two sets of paths, like "git log -p".
After "git log -p" finishes showing a single commit, calling it
before it goes on to the next commit is NOT fine. There is a
mechanism, the .no_free member in diff_options struct, to help "git
log" to avoid calling diff_free() after showing each commit and
instead call it just one. When the mechanism was introduced in
e900d494 (diff: add an API for deferred freeing, 2021-02-11),
however, we forgot to do the same to "diff-tree --stdin", which *is*
a moral equivalent to "git log".
During 2.36 release cycle, we started clearing the pathspec in
diff_free(), so programs like gitk that runs
git diff-tree --stdin -- <pathspec>
downstream of a pipe, processing one commit after another, started
showing irrelevant comparison outside the given <pathspec> from the
second commit. The same commit, by forgetting to teach the .no_free
mechanism, broke "diff-tree --stdin -I<regexp>" and nobody noticed
it for over a year, presumably because it is so seldom used an
option.
But <pathspec> is a different story. The breakage was very
prominently visible and was reported immediately after 2.36 was
released.
Fix this breakage by mimicking how "git log" utilizes the .no_free
member so that "diff-tree --stdin" behaves more similarly to "log".
Protect the fix with a few new tests.
Reported-by: Matthias Aßhauer <mha1993@live.de>
Helped-by: René Scharfe <l.s.r@web.de>
Helped-by: Phillip Wood <phillip.wood123@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This reverts commit 2d53975488.
3656f84278 (name-rev: prefer shorter names over following merges,
2021-12-04) broke the assumption of 2d53975488 (name-rev: release unused
name strings, 2020-02-04) that a better name for a child is a better
name for all of its ancestors as well, because it added a penalty for
generation > 0. This leads to strings being free(3)'d that are still
needed.
079f970971 (name-rev: sort tip names before applying, 2020-02-05)
already reduced the number of free(3) calls for the use case that
motivated the original patch (name-rev --all in the Chromium repository)
from ca. 44000 to 5, and 3656f84278 eliminated even those few. So this
revert won't affect name-rev's performance on that particular repo.
Reported-by: Thomas Hurst <tom@hur.st>
Helped-by: Elijah Newren <newren@gmail.com>
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix a regression in 707d2f2fe8 (CI: use "$runs_on_pool", not
"$jobname" to select packages & config, 2021-11-23).
In that commit I changed CC=gcc from CC=gcc-9, but on OSX the "gcc" in
$PATH points to clang, we need to use gcc-9 instead. Likewise for the
linux-gcc job CC=gcc-8 was changed to the implicit CC=gcc, which would
select GCC 9.4.0 instead of GCC 8.4.0.
Furthermore in 25715419bf (CI: don't run "make test" twice in one
job, 2021-11-23) when the "linux-TEST-vars" job was split off from
"linux-gcc" the "cc_package: gcc-8" line was copied along with
it, so its "cc_package" line wasn't working as intended either.
As a table, this is what's changed by this commit, i.e. it only
affects the linux-gcc, linux-TEST-vars and osx-gcc jobs:
|-------------------+-----------+-------------------+-------+-------|
| jobname | vector.cc | vector.cc_package | old | new |
|-------------------+-----------+-------------------+-------+-------|
| linux-clang | clang | - | clang | clang |
| linux-sha256 | clang | - | clang | clang |
| linux-gcc | gcc | gcc-8 | gcc | gcc-8 |
| osx-clang | clang | - | clang | clang |
| osx-gcc | gcc | gcc-9 | clang | gcc-9 |
| linux-gcc-default | gcc | - | gcc | gcc |
| linux-TEST-vars | gcc | gcc-8 | gcc | gcc-8 |
|-------------------+-----------+-------------------+-------+-------|
Reported-by: Carlo Arenas <carenas@gmail.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
On Windows, git repositories may have extra files which need cleaned
(e.g., a build directory) that may be arbitrarily deep. Suggest using
`core.longPaths` if such situations are encountered.
Fixes: #2715
Signed-off-by: Ben Boeckel <mathstuf@gmail.com>
At least in systems where the user is local and not an administrator
git will install in a subdirectory of %APPDATALOCAL%, so it makes
sense to also look there for the shell needed by the cmake integration
with Visual Studio.
The first three commits are rebased versions of those in gitgitgadget/git#1215. These allow the following:
1. Fix `git config --global foo.bar <path>` from allowing the `<path>`. As a bonus, users with a config value starting with `/` will not get a warning about "old-style" paths needing a "`%(prefix)/`".
2. When in WSL, the path starts with `/` so it needs to be interpolated properly. Update the warning to include `%(prefix)/` to get the right value for WSL users. (This is specifically for using Git for Windows from Git Bash, but in a WSL directory.)
3. When using WSL, the ownership check fails and reports an error message. This is noisy, and happens even if the user has marked the path with `safe.directory`. Remove that error message.
In the case of Git for Windows (say, in a Git Bash window) running in a
Windows Subsystem for Linux (WSL) directory, the GetNamedSecurityInfoW()
call in is_path_owned_By_current_side() returns an error code other than
ERROR_SUCCESS. This is consistent behavior across this boundary.
In these cases, the owner would always be different because the WSL
owner is a different entity than the Windows user.
The change here is to suppress the error message that looks like this:
error: failed to get owner for '//wsl.localhost/...' (1)
Before this change, this warning happens for every Git command,
regardless of whether the directory is marked with safe.directory.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
After attempting to add directory on a network share to the `safe.directory` configuration with, for example:
```
git config --global --add safe.directory //servername/repos/myrepo
```
The warning about an outdated path style:
```
warning: encountered old-style '//servername/repos/myrepo' that should be '%(prefix)//servername/repos/myrepo'
```
However, the warning is missing a trailing `/` behind the prefix.
This PR fixes the warning such that the resulting configuration works.
Also see https://stackoverflow.com/a/71859164/4473230Closes#3786
Git for Windows v2.35.2
Changes since Git for Windows v2.35.1(2) (February 1st 2022)
This version addresses CVE-2022-24765 and CVE-2022-24767.
New Features
* Comes with Git v2.35.2.
Bug Fixes
* The uninstaller was hardened to avoid a vulnerability when running
under the SYSTEM account, addressing CVE-2022-24767.
Signed-off-by: Victoria Dye <vdye@github.com>
When an Administrator creates a file or directory, the created
file/directory is owned not by the Administrator SID, but by the
_Administrators Group_ SID. The reason is that users with administrator
privileges usually run in unprivileged ("non-elevated") mode, and their
user SID does not change when running in elevated mode.
This is is relevant e.g. when running a GitHub workflow on a build
agent, which runs in elevated mode: cloning a Git repository in a script
step will cause the worktree to be owned by the Administrators Group
SID, for example.
Let's handle this case as following: if the current user is an
administrator, Git should consider a worktree owned by the
Administrators Group as if it were owned by said user.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When Git refuses to use an existing repository because it is owned by
someone else than the current user, it can be a bit tricky on Windows to
figure out what is going on.
Let's help with that by offering some more information via the
environment variable `GIT_TEST_DEBUG_UNSAFE_DIRECTORIES`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The `--preserve-merges` option was removed by v2.35.0. However
users may not be aware that it is also a Pull option, and it is
still offered by major IDE vendors such as Visual Studio.
Extend the `--preserve-merges` die message to direct users to
this option and it's locations.
Signed-off-by: Philip Oakley <philipoakley@iee.email>
Git will die if a "rebase --preserve-merges" is in progress.
Users cannot --quit, --abort or --continue the rebase.
This sceario can occur if the user updates their Git, or switches
to another newer version, after starting a preserve-merges rebase,
commonly via the pull setting.
One trigger is an unexpectedly difficult to resolve conflict, as
reported on the `git-users` group.
(https://groups.google.com/g/git-for-windows/c/3jMWbBlXXHM)
Tell the user the cause, i.e. the existence of the directory.
The problem must be resolved manually, `git rebase --<option>`
commands will die, or the user must downgrade. Also, note that
the deleted options are no longer shown in the documentation.
Signed-off-by: Philip Oakley <philipoakley@iee.email>
Previously, we interpolated paths in config variables that start with a
forward-slash as relative to the runtime prefix. This was not portable
and has been replaced with `%(prefix)/`.
Let's warn users when they use the now-deprecated form.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This topic branch re-adds the deprecated --stdin/-z options to `git
reset`. Those patches were overridden by a different set of options in
the upstream Git project before we could propose `--stdin`.
We offered this in MinGit to applications that wanted a safer way to
pass lots of pathspecs to Git, and these applications will need to be
adjusted.
Instead of `--stdin`, `--pathspec-from-file=-` should be used, and
instead of `-z`, `--pathspec-file-nul`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This branch allows third-party tools to call `git status
--no-lock-index` to avoid lock contention with the interactive Git usage
of the actual human user.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
A fix for calling `vim` in Windows Terminal caused a regression and was
reverted. We partially un-revert this, to get the fix again.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
