space utilization and performance. This option will cause
'git gc' to more aggressively optimize the repository at the expense
of taking much more time. The effects of this optimization are
- persistent, so this option only needs to be used occasionally; every
- few hundred changesets or so.
+ mostly persistent. See the "AGGRESSIVE" section below for details.
--auto::
With this option, 'git gc' checks whether any housekeeping is
`.keep` files are consolidated into a single pack. When this
option is used, `gc.bigPackThreshold` is ignored.
+AGGRESSIVE
+----------
+
+When the `--aggressive` option is supplied, linkgit:git-repack[1] will
+be invoked with the `-f` flag, which in turn will pass
+`--no-reuse-delta` to linkgit:git-pack-objects[1]. This will throw
+away any existing deltas and re-compute them, at the expense of
+spending much more time on the repacking.
+
+The effects of this are mostly persistent, e.g. when packs and loose
+objects are coalesced into one another pack the existing deltas in
+that pack might get re-used, but there are also various cases where we
+might pick a sub-optimal delta from a newer pack instead.
+
+Furthermore, supplying `--aggressive` will tweak the `--depth` and
+`--window` options passed to linkgit:git-repack[1]. See the
+`gc.aggressiveDepth` and `gc.aggressiveWindow` settings below. By
+using a larger window size we're more likely to find more optimal
+deltas.
+
+It's probably not worth it to use this option on a given repository
+without running tailored performance benchmarks on it. It takes a lot
+more time, and the resulting space/delta optimization may or may not
+be worth it. Not using this at all is the right trade-off for most
+users and their repositories.
+
CONFIGURATION
-------------
particular, it will keep not only objects referenced by your current set
of branches and tags, but also objects referenced by the index,
remote-tracking branches, refs saved by 'git filter-branch' in
-refs/original/, or reflogs (which may reference commits in branches
-that were later amended or rewound).
+refs/original/, reflogs (which may reference commits in branches
+that were later amended or rewound), and anything else in the refs/* namespace.
If you are expecting some objects to be deleted and they aren't, check
all of those locations and decide whether it makes sense in your case to
remove those references.
However, these features fall short of a complete solution, so users who
run commands concurrently have to live with some risk of corruption (which
-seems to be low in practice) unless they turn off automatic garbage
-collection with 'git config gc.auto 0'.
+seems to be low in practice).
HOOKS
-----