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>
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>
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>
If `feature.experimental` and `feature.manyFiles` are set and the user
has not explicitly turned off the builtin FSMonitor, we now start
the built-in FSMonitor by default.
Only forcing it when UNSET matches the behavior of UPDATE_DEFAULT_BOOL()
used for other repo settings.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Create unit tests to move a directory. Verify that `git status`
gives the same result with and without FSMonitor enabled.
NEEDSWORK: This test exposes a bug in the untracked-cache on
Windows when FSMonitor is disabled. These are commented out
for the moment.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Teach Git to perform binary search over the cache-entries for a directory
notification and then linearly scan forward to find the immediate children.
Previously, when the FSMonitor reported a modified directory Git would
perform a linear search on the entire cache-entry array for all
entries matching that directory prefix and invalidate them. Since the
cache-entry array is already sorted, we can use a binary search to
find the first matching entry and then only linearly walk forward and
invalidate entries until the prefix changes.
Also, the original code would invalidate anything having the same
directory prefix. Since a directory event should only be received for
items that are immediately within the directory (and not within
sub-directories of it), only invalidate those entries and not the
whole subtree.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Create 2x2 test matrix with the untracked-cache and fsmonitor--daemon
features and a series of edits and verify that status output is
identical.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
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>
