unpack-trees: enable fscache for sparse-checkout #151
Conversation
|
With this change, running A more involved change could recognize the missing parent folder and stop recursing on all lower folders. |
|
This applies only to git-for-windows so this PR is mirrored in git-for-windows#2224. |
Does the file system guarantee that if a file that is deep within the directory structure is changed all the modified timestamps of parent folders are updated? Or does that not matter in this case where it is only updating the |
|
@kewillford The file system DOES NOT propagate the mtime changes up the tree. If a file is created or deleted, the mtime on the immediate parent directory is updated, but that's about it. In particular, modifying a file does not affect the mtime of the parent directory. |
When updating the skip-worktree bits in the index to align with new values in a sparse-checkout file, Git scans the entire working directory with lstat() calls. In a sparse-checkout, many of these lstat() calls are for paths that do not exist. Enable the fscache feature during this scan. Since enable_fscache() calls nest, the disable_fscache() method decrements a counter and would only clear the cache if that counter reaches zero. In a local test of a repo with ~2.2 million paths, updating the index with git read-tree -m -u HEAD with a sparse-checkout file containing only /.gitattributes improved from 2-3 minutes to ~6 seconds. Signed-off-by: Derrick Stolee <[email protected]>
derrickstolee
force-pushed
the
fscache-sparse
branch
from
143bfe9 to
f392fab
Compare
|
Merged in git-for-windows/git. |
When updating the skip-worktree bits in the index to align with new
values in a sparse-checkout file, Git scans the entire working
directory with lstat() calls. In a sparse-checkout, many of these
lstat() calls are for paths that do not exist.
Enable the fscache feature during this scan.