Teach FSCACHE to remember "not found" directories.
This is a performance optimization.
FSCACHE is a performance optimization available for Windows. It
intercepts Posix-style lstat() calls into an in-memory directory
using FindFirst/FindNext. It improves performance on Windows by
catching the first lstat() call in a directory, using FindFirst/
FindNext to read the list of files (and attribute data) for the
entire directory into the cache, and short-cut subsequent lstat()
calls in the same directory. This gives a major performance
boost on Windows.
However, it does not remember "not found" directories. When STATUS
runs and there are missing directories, the lstat() interception
fails to find the parent directory and simply return ENOENT for the
file -- it does not remember that the FindFirst on the directory
failed. Thus subsequent lstat() calls in the same directory, each
re-attempt the FindFirst. This completely defeats any performance
gains.
This can be seen by doing a sparse-checkout on a large repo and
then doing a read-tree to reset the skip-worktree bits and then
running status.
This change reduced status times for my very large repo by 60%.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
If multiple threads access a directory that is not yet in the cache, the
directory will be loaded by each thread. Only one of the results is added
to the cache, all others are leaked. This wastes performance and memory.
On cache miss, add a future object to the cache to indicate that the
directory is currently being loaded. Subsequent threads register themselves
with the future object and wait. When the first thread has loaded the
directory, it replaces the future object with the result and notifies
waiting threads.
Signed-off-by: Karsten Blees <blees@dcon.de>
Checking the work tree status is quite slow on Windows, due to slow
`lstat()` emulation (git calls `lstat()` once for each file in the
index). Windows operating system APIs seem to be much better at scanning
the status of entire directories than checking single files.
Add an `lstat()` implementation that uses a cache for lstat data. Cache
misses read the entire parent directory and add it to the cache.
Subsequent `lstat()` calls for the same directory are served directly
from the cache.
Also implement `opendir()`/`readdir()`/`closedir()` so that they create
and use directory listings in the cache.
The cache doesn't track file system changes and doesn't plug into any
modifying file APIs, so it has to be explicitly enabled for git functions
that don't modify the working copy.
Note: in an earlier version of this patch, the cache was always active and
tracked file system changes via ReadDirectoryChangesW. However, this was
much more complex and had negative impact on the performance of modifying
git commands such as 'git checkout'.
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Add a macro to mark code sections that only read from the file system,
along with a config option and documentation.
This facilitates implementation of relatively simple file system level
caches without the need to synchronize with the file system.
Enable read-only sections for 'git status' and preload_index.
Signed-off-by: Karsten Blees <blees@dcon.de>
Emulating the POSIX lstat API on Windows via GetFileAttributes[Ex] is quite
slow. Windows operating system APIs seem to be much better at scanning the
status of entire directories than checking single files. A caching
implementation may improve performance by bulk-reading entire directories
or reusing data obtained via opendir / readdir.
Make the lstat implementation pluggable so that it can be switched at
runtime, e.g. based on a config option.
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Emulating the POSIX `dirent` API on Windows via
`FindFirstFile()`/`FindNextFile()` is pretty staightforward, however,
most of the information provided in the `WIN32_FIND_DATA` structure is
thrown away in the process. A more sophisticated implementation may
cache this data, e.g. for later reuse in calls to `lstat()`.
Make the `dirent` implementation pluggable so that it can be switched at
runtime, e.g. based on a config option.
Define a base DIR structure with pointers to `readdir()`/`closedir()`
that match the `opendir()` implementation (similar to vtable pointers in
Object-Oriented Programming). Define `readdir()`/`closedir()` so that
they call the function pointers in the `DIR` structure. This allows to
choose the `opendir()` implementation on a call-by-call basis.
Make the fixed-size `dirent.d_name` buffer a flex array, as `d_name` may
be implementation specific (e.g. a caching implementation may allocate a
`struct dirent` with _just_ the size needed to hold the `d_name` in
question).
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We will use them in the upcoming "FSCache" patches (to accelerate
sequential lstat() calls).
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This is the branch thicket of patches in Git for Windows that are
considered ready for upstream. To keep them in a ready-to-submit shape,
they are kept as close to the beginning of the branch thicket as
possible.
This merges the current version of the patch that tries to address Git
GUI's problems with intent-to-add files.
This patch will likely be improved substantially before it is merged
into Git GUI's main branch, but we want to have _something_ resembling a
fix already in Git for Windows v2.29.0.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This topic branch allows `add -p` and `add -i` with a large number of
files. It is kind of a hack that was never really meant to be
upstreamed. Let's see if we can do better in the built-in `add -p`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In MSYS2, we have two Python interpreters at our disposal, so we can
include the Python stuff in the build.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Make `git config --system` work like you think it should on Windows: it
should edit the file that is located in `<Git>\etc\gitconfig`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This topic branch teaches `git clean` to respect NTFS junctions and Unix
bind mounts: it will now stop at those boundaries.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This topic branch avoids spawning `gzip` when asking `git archive` to
create `.tar.gz` files.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When compiling Git with a runtime prefix (so that it can be installed
into any location, finding its libexec/ directory relative to the
location of the `git` executable), it is convenient to provide
"absolute" Unix-y paths e.g. for http.sslCAInfo, and have those absolute
paths be resolved relative to the runtime prefix.
This patch makes it so for Windows. It is up for discussion whether we
want this for other platforms, too, as long as building with
RUNTIME_PREFIX.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This topic branch allows us to specify absolute paths without the drive
prefix e.g. when cloning.
Example:
C:\Users\me> git clone https://github.com/git/git \upstream-git
This will clone into a new directory C:\upstream-git, in line with how
Windows interprets absolute paths.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
These fixes were necessary for Sverre Rabbelier's remote-hg to work,
but for some magic reason they are not necessary for the current
remote-hg. Makes you wonder how that one gets away with it.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When building the Pacman packages, we technically do not need the full
`build-installers` artifact (which is substantially larger than the
`makepkg-git` artifact). However, the former is already cached and
includes the latter's files. And it is _so_ much faster to download the
cached (larger) artifact than to download the smaller `makepkg-git`
artifact from Azure Pipelines.
Suggested-by: Dennis Ameling <dennis@dennisameling.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
It is a bit expensive to fetch just the git-sdk-64-build-installers
artifact from Azure Pipelines and then to unpack it (takes some 6-7
minutes, typically). Let's cache it if possible.
Signed-off-by: Dennis Ameling <dennis@dennisameling.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
With this change, users can specify the branch and repository from which
they want to build Git for Windows' artifacts, via the `ref` and
`repository` inputs.
This allows e.g. building `refs/heads/seen` of `git/git` (even if no
`git-artifacts` workflow is configured in that repository), or
`refs/pull/<number>/merge` for a given Pull Request.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This commit adds a step called "initialize vcpkg" to the GitHub Actions
workflow, because we need some build scripts from vcpkg that aren't
present in our vcpkg artifacts from Azure Pipelines.
Signed-off-by: Dennis Ameling <dennis@dennisameling.com>
By mistake, the `.exe` extension is appended _twice_ when installing the
dashed executables into `libexec/git-core/` on Windows (the extension is
already appended when adding items to the `git_links` list in the
`#Creating hardlinks` section).
Signed-off-by: Dennis Ameling <dennis@dennisameling.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Users can now specify which artifacts they want to build, via the
`build_only` input, which is a space-separated list of artifacts. For
example, `installer portable` will build `installer-x86_64`,
`installer-i686`, `portable-x86_64` and `portable-i686`, and an empty or
unset value will build all artifacts.
Please note that the `mingw-w64-git` packages are built always, as it
would be tricky to figure out when they need to be built (for example,
`build_only=portable-x86_64` technically does not need `pkg-i686` to be
built, while `build_only=portable` does).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
