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Diffstat (limited to 'Documentation/git-update-index.txt')
| -rw-r--r-- | Documentation/git-update-index.txt | 118 |
1 files changed, 108 insertions, 10 deletions
diff --git a/Documentation/git-update-index.txt b/Documentation/git-update-index.txt index 7386c93162..3897a59ee9 100644 --- a/Documentation/git-update-index.txt +++ b/Documentation/git-update-index.txt @@ -16,9 +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>] @@ -111,6 +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 @@ -153,7 +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. @@ -163,14 +171,16 @@ 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:: @@ -199,6 +209,15 @@ will remove the intended effect of the option. `--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. @@ -212,7 +231,7 @@ will remove the intended effect of the option. 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 +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. @@ -388,6 +407,31 @@ 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 +$GIT_DIR/index, the split index, while the shared index file contains +all index entries and stays unchanged. + +All changes in the split index are pushed back to the shared index +file when the number of entries in the split index reaches a level +specified by the splitIndex.maxPercentChange config variable (see +linkgit:git-config[1]). + +Each time a new shared index file is created, the old shared index +files are deleted if their modification time is older than what is +specified by the splitIndex.sharedIndexExpire config variable (see +linkgit:git-config[1]). + +To avoid deleting a shared index file that is still used, its +modification time is updated to the current time everytime a new split +index based on the shared index file is either created or read from. + Untracked cache --------------- @@ -420,6 +464,60 @@ command reads the index; while when `--[no-|force-]untracked-cache` are used, the untracked cache is immediately added to or removed from the index. +Before 2.17, the untracked cache had a bug where replacing a directory +with a symlink to another directory could cause it to incorrectly show +files tracked by git as untracked. See the "status: add a failing test +showing a core.untrackedCache bug" commit to git.git. A workaround for +that is (and this might work for other undiscovered bugs in the +future): + +---------------- +$ git -c core.untrackedCache=false status +---------------- + +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 ------------- |