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Diffstat (limited to 'Documentation/git-update-index.txt')
| -rw-r--r-- | Documentation/git-update-index.txt | 228 |
1 files changed, 193 insertions, 35 deletions
diff --git a/Documentation/git-update-index.txt b/Documentation/git-update-index.txt index aff01798cd..1c4d146a41 100644 --- a/Documentation/git-update-index.txt +++ b/Documentation/git-update-index.txt @@ -16,7 +16,11 @@ SYNOPSIS [--chmod=(+|-)x] [--[no-]assume-unchanged] [--[no-]skip-worktree] + [--[no-]fsmonitor-valid] [--ignore-submodules] + [--[no-]split-index] + [--[no-|test-|force-]untracked-cache] + [--[no-]fsmonitor] [--really-refresh] [--unresolve] [--again | -g] [--info-only] [--index-info] [-z] [--stdin] [--index-version <n>] @@ -100,7 +104,7 @@ thus, in case the assumed-untracked file is changed upstream, you will need to handle the situation manually. --really-refresh:: - Like '--refresh', but checks stat information unconditionally, + Like `--refresh`, but checks stat information unconditionally, without regard to the "assume unchanged" setting. --[no-]skip-worktree:: @@ -109,6 +113,12 @@ you will need to handle the situation manually. set and unset the "skip-worktree" bit for the paths. See section "Skip-worktree bit" below for more information. +--[no-]fsmonitor-valid:: + When one of these flags is specified, the object name recorded + for the paths are not updated. Instead, these options + set and unset the "fsmonitor valid" bit for the paths. See + section "File System Monitor" below for more information. + -g:: --again:: Runs 'git update-index' itself on the paths whose index @@ -151,7 +161,7 @@ you will need to handle the situation manually. + Version 4 performs a simple pathname compression that reduces index size by 30%-50% on large repositories, which results in faster load -time. Version 4 is relatively young (first released in in 1.8.0 in +time. Version 4 is relatively young (first released in 1.8.0 in October 2012). Other Git implementations such as JGit and libgit2 may not support it yet. @@ -161,14 +171,52 @@ may not support it yet. --split-index:: --no-split-index:: - Enable or disable split index mode. If enabled, the index is - split into two files, $GIT_DIR/index and $GIT_DIR/sharedindex.<SHA-1>. - Changes are accumulated in $GIT_DIR/index while the shared - index file contains all index entries stays unchanged. If - split-index mode is already enabled and `--split-index` is - given again, all changes in $GIT_DIR/index are pushed back to - the shared index file. This mode is designed for very large - indexes that take a significant amount of time to read or write. + Enable or disable split index mode. If split-index mode is + already enabled and `--split-index` is given again, all + changes in $GIT_DIR/index are pushed back to the shared index + file. ++ +These options take effect whatever the value of the `core.splitIndex` +configuration variable (see linkgit:git-config[1]). But a warning is +emitted when the change goes against the configured value, as the +configured value will take effect next time the index is read and this +will remove the intended effect of the option. + +--untracked-cache:: +--no-untracked-cache:: + Enable or disable untracked cache feature. Please use + `--test-untracked-cache` before enabling it. ++ +These options take effect whatever the value of the `core.untrackedCache` +configuration variable (see linkgit:git-config[1]). But a warning is +emitted when the change goes against the configured value, as the +configured value will take effect next time the index is read and this +will remove the intended effect of the option. + +--test-untracked-cache:: + Only perform tests on the working directory to make sure + untracked cache can be used. You have to manually enable + untracked cache using `--untracked-cache` or + `--force-untracked-cache` or the `core.untrackedCache` + configuration variable afterwards if you really want to use + it. If a test fails the exit code is 1 and a message + explains what is not working as needed, otherwise the exit + code is 0 and OK is printed. + +--force-untracked-cache:: + Same as `--untracked-cache`. Provided for backwards + compatibility with older versions of Git where + `--untracked-cache` used to imply `--test-untracked-cache` but + this option would enable the extension unconditionally. + +--fsmonitor:: +--no-fsmonitor:: + Enable or disable files system monitor feature. These options + take effect whatever the value of the `core.fsmonitor` + configuration variable (see linkgit:git-config[1]). But a warning + is emitted when the change goes against the configured value, as + the configured value will take effect next time the index is + read and this will remove the intended effect of the option. \--:: Do not interpret any more arguments as options. @@ -180,10 +228,10 @@ may not support it yet. cleaner names. The same applies to directories ending '/' and paths with '//' -Using --refresh +USING --REFRESH --------------- -'--refresh' does not calculate a new sha1 file or bring the index -up-to-date for mode/content changes. But what it *does* do is to +`--refresh` does not calculate a new sha1 file or bring the index +up to date for mode/content changes. But what it *does* do is to "re-match" the stat information of a file with the index, so that you can refresh the index for a file that hasn't been changed but where the stat entry is out of date. @@ -191,52 +239,49 @@ the stat entry is out of date. For example, you'd want to do this after doing a 'git read-tree', to link up the stat index details with the proper files. -Using --cacheinfo or --info-only +USING --CACHEINFO OR --INFO-ONLY -------------------------------- -'--cacheinfo' is used to register a file that is not in the +`--cacheinfo` is used to register a file that is not in the current working directory. This is useful for minimum-checkout merging. -To pretend you have a file with mode and sha1 at path, say: +To pretend you have a file at path with mode and sha1, say: ---------------- -$ git update-index --cacheinfo <mode>,<sha1>,<path> +$ git update-index --add --cacheinfo <mode>,<sha1>,<path> ---------------- -'--info-only' is used to register files without placing them in the object +`--info-only` is used to register files without placing them in the object database. This is useful for status-only repositories. -Both '--cacheinfo' and '--info-only' behave similarly: the index is updated -but the object database isn't. '--cacheinfo' is useful when the object is -in the database but the file isn't available locally. '--info-only' is +Both `--cacheinfo` and `--info-only` behave similarly: the index is updated +but the object database isn't. `--cacheinfo` is useful when the object is +in the database but the file isn't available locally. `--info-only` is useful when the file is available, but you do not wish to update the object database. -Using --index-info +USING --INDEX-INFO ------------------ `--index-info` is a more powerful mechanism that lets you feed multiple entry definitions from the standard input, and designed specifically for scripts. It can take inputs of three formats: - . mode SP sha1 TAB path -+ -The first format is what "git-apply --index-info" -reports, and used to reconstruct a partial tree -that is used for phony merge base tree when falling -back on 3-way merge. - . mode SP type SP sha1 TAB path + -The second format is to stuff 'git ls-tree' output -into the index file. +This format is to stuff `git ls-tree` output into the index. . mode SP sha1 SP stage TAB path + This format is to put higher order stages into the index file and matches 'git ls-files --stage' output. + . mode SP sha1 TAB path ++ +This format is no longer produced by any Git command, but is +and will continue to be supported by `update-index --index-info`. + To place a higher stage entry to the index, the path should first be removed by feeding a mode=0 entry for the path, and then feeding necessary input lines in the third format. @@ -269,7 +314,7 @@ $ git ls-files -s ------------ -Using ``assume unchanged'' bit +USING ``ASSUME UNCHANGED'' BIT ------------------------------ Many operations in Git depend on your filesystem to have an @@ -302,7 +347,7 @@ the index (use `git update-index --really-refresh` if you want to mark them as "assume unchanged"). -Examples +EXAMPLES -------- To update and refresh only the files already checked out: @@ -339,7 +384,7 @@ M foo.c <9> now it checks with lstat(2) and finds it has been changed. -Skip-worktree bit +SKIP-WORKTREE BIT ----------------- Skip-worktree bit can be defined in one (long) sentence: When reading @@ -359,8 +404,118 @@ Although this bit looks similar to assume-unchanged bit, its goal is different from assume-unchanged bit's. Skip-worktree also takes precedence over assume-unchanged bit when both are set. +SPLIT INDEX +----------- + +This mode is designed for repositories with very large indexes, and +aims at reducing the time it takes to repeatedly write these indexes. + +In this mode, the index is split into two files, $GIT_DIR/index and +$GIT_DIR/sharedindex.<SHA-1>. Changes are accumulated in +$GIT_DIR/index, the split index, while the shared index file contains +all index entries and stays unchanged. + +All changes in the split index are pushed back to the shared index +file when the number of entries in the split index reaches a level +specified by the splitIndex.maxPercentChange config variable (see +linkgit:git-config[1]). + +Each time a new shared index file is created, the old shared index +files are deleted if their modification time is older than what is +specified by the splitIndex.sharedIndexExpire config variable (see +linkgit:git-config[1]). + +To avoid deleting a shared index file that is still used, its +modification time is updated to the current time everytime a new split +index based on the shared index file is either created or read from. + +UNTRACKED CACHE +--------------- + +This cache is meant to speed up commands that involve determining +untracked files such as `git status`. + +This feature works by recording the mtime of the working tree +directories and then omitting reading directories and stat calls +against files in those directories whose mtime hasn't changed. For +this to work the underlying operating system and file system must +change the `st_mtime` field of directories if files in the directory +are added, modified or deleted. + +You can test whether the filesystem supports that with the +`--test-untracked-cache` option. The `--untracked-cache` option used +to implicitly perform that test in older versions of Git, but that's +no longer the case. + +If you want to enable (or disable) this feature, it is easier to use +the `core.untrackedCache` configuration variable (see +linkgit:git-config[1]) than using the `--untracked-cache` option to +`git update-index` in each repository, especially if you want to do so +across all repositories you use, because you can set the configuration +variable to `true` (or `false`) in your `$HOME/.gitconfig` just once +and have it affect all repositories you touch. + +When the `core.untrackedCache` configuration variable is changed, the +untracked cache is added to or removed from the index the next time a +command reads the index; while when `--[no-|force-]untracked-cache` +are used, the untracked cache is immediately added to or removed from +the index. + +Before 2.17, the untracked cache had a bug where replacing a directory +with a symlink to another directory could cause it to incorrectly show +files tracked by git as untracked. See the "status: add a failing test +showing a core.untrackedCache bug" commit to git.git. A workaround for +that is (and this might work for other undiscovered bugs in the +future): + +---------------- +$ git -c core.untrackedCache=false status +---------------- -Configuration +This bug has also been shown to affect non-symlink cases of replacing +a directory with a file when it comes to the internal structures of +the untracked cache, but no case has been reported where this resulted in +wrong "git status" output. + +There are also cases where existing indexes written by git versions +before 2.17 will reference directories that don't exist anymore, +potentially causing many "could not open directory" warnings to be +printed on "git status". These are new warnings for existing issues +that were previously silently discarded. + +As with the bug described above the solution is to one-off do a "git +status" run with `core.untrackedCache=false` to flush out the leftover +bad data. + +FILE SYSTEM MONITOR +------------------- + +This feature is intended to speed up git operations for repos that have +large working directories. + +It enables git to work together with a file system monitor (see the +"fsmonitor-watchman" section of linkgit:githooks[5]) that can +inform it as to what files have been modified. This enables git to avoid +having to lstat() every file to find modified files. + +When used in conjunction with the untracked cache, it can further improve +performance by avoiding the cost of scanning the entire working directory +looking for new files. + +If you want to enable (or disable) this feature, it is easier to use +the `core.fsmonitor` configuration variable (see +linkgit:git-config[1]) than using the `--fsmonitor` option to +`git update-index` in each repository, especially if you want to do so +across all repositories you use, because you can set the configuration +variable in your `$HOME/.gitconfig` just once and have it affect all +repositories you touch. + +When the `core.fsmonitor` configuration variable is changed, the +file system monitor is added to or removed from the index the next time +a command reads the index. When `--[no-]fsmonitor` are used, the file +system monitor is immediately added to or removed from the index. + +CONFIGURATION ------------- The command honors `core.filemode` configuration variable. If @@ -384,6 +539,9 @@ It can be useful when the inode change time is regularly modified by something outside Git (file system crawlers and backup systems use ctime for marking files processed) (see linkgit:git-config[1]). +The untracked cache extension can be enabled by the +`core.untrackedCache` configuration variable (see +linkgit:git-config[1]). SEE ALSO -------- |