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Diffstat (limited to 'Documentation/git-maintenance.txt')
| -rw-r--r-- | Documentation/git-maintenance.txt | 101 |
1 files changed, 99 insertions, 2 deletions
diff --git a/Documentation/git-maintenance.txt b/Documentation/git-maintenance.txt index 3f5d8946b4..6fe1e5e105 100644 --- a/Documentation/git-maintenance.txt +++ b/Documentation/git-maintenance.txt @@ -29,6 +29,32 @@ Git repository. SUBCOMMANDS ----------- +register:: + Initialize Git config values so any scheduled maintenance will + start running on this repository. This adds the repository to the + `maintenance.repo` config variable in the current user's global + config and enables some recommended configuration values for + `maintenance.<task>.schedule`. The tasks that are enabled are safe + for running in the background without disrupting foreground + processes. ++ +The `register` subcommand will also set the `maintenance.strategy` config +value to `incremental`, if this value is not previously set. The +`incremental` strategy uses the following schedule for each maintenance +task: ++ +-- +* `gc`: disabled. +* `commit-graph`: hourly. +* `prefetch`: hourly. +* `loose-objects`: daily. +* `incremental-repack`: daily. +-- ++ +`git maintenance register` will also disable foreground maintenance by +setting `maintenance.auto = false` in the current repository. This config +setting will remain after a `git maintenance unregister` command. + run:: Run one or more maintenance tasks. If one or more `--task` options are specified, then those tasks are run in that order. Otherwise, @@ -36,6 +62,22 @@ run:: config options are true. By default, only `maintenance.gc.enabled` is true. +start:: + Start running maintenance on the current repository. This performs + the same config updates as the `register` subcommand, then updates + the background scheduler to run `git maintenance run --scheduled` + on an hourly basis. + +stop:: + Halt the background maintenance schedule. The current repository + is not removed from the list of maintained repositories, in case + the background maintenance is restarted later. + +unregister:: + Remove the current repository from background maintenance. This + only removes the repository from the configured list. It does not + stop the background maintenance processes from running. + TASKS ----- @@ -59,7 +101,7 @@ This is done to avoid disrupting the remote-tracking branches. The end users expect these refs to stay unmoved unless they initiate a fetch. With prefetch task, however, the objects necessary to complete a later real fetch would already be obtained, so the real fetch would go faster. In the ideal case, -it will just become an update to bunch of remote-tracking branches without +it will just become an update to a bunch of remote-tracking branches without any object transfer. gc:: @@ -110,7 +152,18 @@ OPTIONS only if certain thresholds are met. For example, the `gc` task runs when the number of loose objects exceeds the number stored in the `gc.auto` config setting, or when the number of pack-files - exceeds the `gc.autoPackLimit` config setting. + exceeds the `gc.autoPackLimit` config setting. Not compatible with + the `--schedule` option. + +--schedule:: + When combined with the `run` subcommand, run maintenance tasks + only if certain time conditions are met, as specified by the + `maintenance.<task>.schedule` config value for each `<task>`. + This config value specifies a number of seconds since the last + time that task ran, according to the `maintenance.<task>.lastRun` + config value. The tasks that are tested are those provided by + the `--task=<task>` option(s) or those with + `maintenance.<task>.enabled` set to true. --quiet:: Do not report progress or other information over `stderr`. @@ -122,6 +175,50 @@ OPTIONS `maintenance.<task>.enabled` configured as `true` are considered. See the 'TASKS' section for the list of accepted `<task>` values. + +TROUBLESHOOTING +--------------- +The `git maintenance` command is designed to simplify the repository +maintenance patterns while minimizing user wait time during Git commands. +A variety of configuration options are available to allow customizing this +process. The default maintenance options focus on operations that complete +quickly, even on large repositories. + +Users may find some cases where scheduled maintenance tasks do not run as +frequently as intended. Each `git maintenance run` command takes a lock on +the repository's object database, and this prevents other concurrent +`git maintenance run` commands from running on the same repository. Without +this safeguard, competing processes could leave the repository in an +unpredictable state. + +The background maintenance schedule runs `git maintenance run` processes +on an hourly basis. Each run executes the "hourly" tasks. At midnight, +that process also executes the "daily" tasks. At midnight on the first day +of the week, that process also executes the "weekly" tasks. A single +process iterates over each registered repository, performing the scheduled +tasks for that frequency. Depending on the number of registered +repositories and their sizes, this process may take longer than an hour. +In this case, multiple `git maintenance run` commands may run on the same +repository at the same time, colliding on the object database lock. This +results in one of the two tasks not running. + +If you find that some maintenance windows are taking longer than one hour +to complete, then consider reducing the complexity of your maintenance +tasks. For example, the `gc` task is much slower than the +`incremental-repack` task. However, this comes at a cost of a slightly +larger object database. Consider moving more expensive tasks to be run +less frequently. + +Expert users may consider scheduling their own maintenance tasks using a +different schedule than is available through `git maintenance start` and +Git configuration options. These users should be aware of the object +database lock and how concurrent `git maintenance run` commands behave. +Further, the `git gc` command should not be combined with +`git maintenance run` commands. `git gc` modifies the object database +but does not take the lock in the same way as `git maintenance run`. If +possible, use `git maintenance run --task=gc` instead of `git gc`. + + GIT --- Part of the linkgit:git[1] suite |