die is not a standard shell function. Use
a different shell code for the example.
Signed-off-by: Elia Pinto <gitter.spiros@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Normally we err on the safe side: if something can be seen as both an
SHA1 and a pathspec, we stop and scream. In checkout, there is one
exception added in 859fdab (git-checkout: improve error messages, detect
ambiguities. - 2008-07-23), to allow the common case "git checkout
branch". Let's document this exception.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Clarify various ways to specify the "revision ranges" in the
documentation.
* po/range-doc:
doc: revisions: sort examples and fix alignment of the unchanged
doc: revisions: show revision expansion in examples
doc: revisions - clarify reachability examples
doc: revisions - define `reachable`
doc: gitrevisions - clarify 'latter case' is revision walk
doc: gitrevisions - use 'reachable' in page description
doc: revisions: single vs multi-parent notation comparison
doc: revisions: extra clarification of <rev>^! notation effects
doc: revisions: give headings for the two and three dot notations
doc: show the actual left, right, and boundary marks
doc: revisions - name the left and right sides
doc: use 'symmetric difference' consistently
Since 4c7f181 (make color.ui default to 'auto', 2013-06-10), the
default for color.* when nothing is set is 'auto' and we still claimed
that the default was 'false'. Be more precise by saying explicitly
that the default is to follow color.ui, and recall that the default is
'auto' to avoid one indirection for the reader.
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The git add --chmod option was introduced in 4e55ed3 ("add: add
--chmod=+x / --chmod=-x options", 2016-05-31), but was never
documented. Document the feature.
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A small doc update.
* hv/doc-commit-reference-style:
SubmittingPatches: use gitk's "Copy commit summary" format
SubmittingPatches: document how to reference previous commits
Correct an age-old calco (is that a typo-like word for calc)
in the documentation.
* ls/packet-line-protocol-doc-fix:
pack-protocol: fix maximum pkt-line size
The "git -c var[=val] cmd" facility to append a configuration
variable definition at the end of the search order was described in
git(1) manual page, but not in git-config(1), which was more likely
place for people to look for when they ask "can I make a one-shot
override, and if so how?"
* dg/document-git-c-in-git-config-doc:
doc: mention `git -c` in git-config(1)
"git push --force-with-lease" already had enough logic to allow
ensuring that such a push results in creation of a ref (i.e. the
receiving end did not have another push from sideways that would be
discarded by our force-pushing), but didn't expose this possibility
to the users. It does so now.
* jk/push-force-with-lease-creation:
t5533: make it pass on case-sensitive filesystems
push: allow pushing new branches with --force-with-lease
push: add shorthand for --force-with-lease branch creation
Documentation/git-push: fix placeholder formatting
The reflog output format is documented better, and a new format
--date=unix to report the seconds-since-epoch (without timezone)
has been added.
* jk/reflog-date:
date: clarify --date=raw description
date: add "unix" format
date: document and test "raw-local" mode
doc/pretty-formats: explain shortening of %gd
doc/pretty-formats: describe index/time formats for %gd
doc/rev-list-options: explain "-g" output formats
doc/rev-list-options: clarify "commit@{Nth}" for "-g" option
"git merge" with renormalization did not work well with
merge-recursive, due to "safer crlf" conversion kicking in when it
shouldn't.
* jc/renormalize-merge-kill-safer-crlf:
merge: avoid "safer crlf" during recording of merge results
convert: unify the "auto" handling of CRLF
Correct an age-old calco (is that a typo-like word for calc)
in the documentation.
* ls/packet-line-protocol-doc-fix:
pack-protocol: fix maximum pkt-line size
According to LARGE_PACKET_MAX in pkt-line.h the maximal length of a
pkt-line packet is 65520 bytes. The pkt-line header takes 4 bytes and
therefore the pkt-line data component must not exceed 65516 bytes.
Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update the suggestion in 175d38ca ("SubmittingPatches: document how
to reference previous commits", 2016-07-28) on the format to refer
to a commit to match what gitk has been giving since last year with
its "Copy commit summary" command; also mention this as one of the
ways to obtain a commit reference in this format.
Signed-off-by: Beat Bolli <dev+git@drbeat.li>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update the documentation about text=auto:
text=auto now follows the core.autocrlf handling when files are not
normalized in the repository.
For a cross platform project recommend the usage of attributes for
line-ending conversions.
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "git -c var[=val] cmd" facility to append a configuration
variable definition at the end of the search order was described in
git(1) manual page, but not in git-config(1), which was more likely
place for people to look for when they ask "can I make a one-shot
override, and if so how?"
* dg/document-git-c-in-git-config-doc:
doc: mention `git -c` in git-config(1)
The man page for `git ls-files --eol` mentions the combination
of text attributes "text=auto eol=lf" or "text=auto eol=crlf" as not
supported yet, but may be in the future.
Now they are supported.
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To reference previous commits people used to put just the
abbreviated SHA-1 into commit messages. This is what has evolved as
a more stable format for referencing commits. So lets document it
for everyone to look-up when needed.
Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The previous commit adjusted the column alignment for revision
examples which show expansion. Fix the unchanged examples and sort
those that show expansions to the end of the list.
Signed-off-by: Philip Oakley <philipoakley@iee.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The revisions examples show the revison arguments and the selected
commits, but do not show the intermediate step of the expansion of
the special 'range' notations. Extend the examples, including an
all-parents multi-parent merge commit example.
Sort the examples and fix the alignment for those unaffected
in the next commit.
Signed-off-by: Philip Oakley <philipoakley@iee.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
For the r1..r2 case, the exclusion of r1, rather than inclusion of r2,
would be the unexpected case in natural language for a simple linear
development, i.e. start..end excludes start.
Signed-off-by: Philip Oakley <philipoakley@iee.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Do not self-define `reachable`, which can lead to misunderstanding.
Instead define `reachability` explictly.
Signed-off-by: Philip Oakley <philipoakley@iee.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The prior sentence has too many clauses for easy parsing.
Replace 'the latter case' with a direct quote.
Signed-off-by: Philip Oakley <philipoakley@iee.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
While there, also break out the other shorthand notations and
add a title for the revision range summary (which also appears
in git-rev-parse, so keep it mixed case).
We do not quote the notation within the headings as the asciidoc ->
docbook -> groff man viewer toolchain, particularly the docbook-groff
step, does not cope with two font changes, failing to return the heading
font to bold after the quotation of the notation.
Signed-off-by: Philip Oakley <philipoakley@iee.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit message is long and has lots of background and
numbers. The summary is: the current default of 250 doesn't
save much space, and costs CPU. It's not a good tradeoff.
Read on for details.
The "--aggressive" flag to git-gc does three things:
1. use "-f" to throw out existing deltas and recompute from
scratch
2. use "--window=250" to look harder for deltas
3. use "--depth=250" to make longer delta chains
Items (1) and (2) are good matches for an "aggressive"
repack. They ask the repack to do more computation work in
the hopes of getting a better pack. You pay the costs during
the repack, and other operations see only the benefit.
Item (3) is not so clear. Allowing longer chains means fewer
restrictions on the deltas, which means potentially finding
better ones and saving some space. But it also means that
operations which access the deltas have to follow longer
chains, which affects their performance. So it's a tradeoff,
and it's not clear that the tradeoff is even a good one.
The existing "250" numbers for "--aggressive" come
originally from this thread:
http://public-inbox.org/git/alpine.LFD.0.9999.0712060803430.13796@woody.linux-foundation.org/
where Linus says:
So when I said "--depth=250 --window=250", I chose those
numbers more as an example of extremely aggressive
packing, and I'm not at all sure that the end result is
necessarily wonderfully usable. It's going to save disk
space (and network bandwidth - the delta's will be re-used
for the network protocol too!), but there are definitely
downsides too, and using long delta chains may
simply not be worth it in practice.
There are some numbers in that thread, but they're mostly
focused on the improved window size, and measure the
improvement from --depth=250 and --window=250 together.
E.g.:
http://public-inbox.org/git/9e4733910712062006l651571f3w7f76ce64c6650dff@mail.gmail.com/
talks about the improved run-time of "git-blame", which
comes from the reduced pack size. But most of that reduction
is coming from --window=250, whereas most of the extra costs
come from --depth=250. There's a link in that thread showing
that increasing the depth beyond 50 doesn't seem to help
much with the size:
https://vcscompare.blogspot.com/2008/06/git-repack-parameters.html
but again, no discussion of the timing impact.
In an earlier thread from Ted Ts'o which discussed setting
the non-aggressive default (from 10 to 50):
http://public-inbox.org/git/20070509134958.GA21489%40thunk.org/
we have more numbers, with the conclusion that going past 50
does not help size much, and hurts the speed of normal
operations.
So from that, we might guess that 50 is actually a sweet
spot, even for aggressive, if we interpret aggressive to
"spend time now to make a better pack". It is not clear that
"--depth=250" is actually a better pack. It may be slightly
_smaller_, but it carries a run-time penalty.
Here are some more recent timings I did to verify that. They
show three things:
- the size of the resulting pack (so disk saved to store,
bandwidth saved on clones/fetches)
- the cost of "rev-list --objects --all", which shows the
effect of the delta chains on trees (commits typically
don't delta, and the command doesn't touch the blobs at
all)
- the cost of "log -Sfoo", which will additionally access
each blob
All cases were repacked with "git repack -adf --depth=$d
--window=250" (so basically, what would happen if we tweaked
the "gc --aggressive" default depth).
The timings are all wall-clock best-of-3. The machine itself
has plenty of RAM compared to the repositories (which is
probably typical of most workstations these days), so we're
really measuring CPU usage, as the whole thing will be in
disk cache after the first run.
The core.deltaBaseCacheLimit is at its default of 96MiB.
It's possible that tweaking it would have some impact on the
tests, as some of them (especially "log -S" on a large repo)
are likely to overflow that. But bumping that carries a
run-time memory cost, so for these tests, I focused on what
we could do just with the on-disk pack tradeoffs.
Each test is done for four depths: 250 (the current value),
50 (the current default that tested well previously), 100
(to show something on the larger side, which previous tests
showed was not a good tradeoff), and 10 (the very old
default, which previous tests showed was worse than 50).
Here are the numbers for linux.git:
depth | size | % | rev-list | % | log -Sfoo | %
-------+-------+-------+----------+--------+-----------+-------
250 | 967MB | n/a | 48.159s | n/a | 378.088 | n/a
100 | 971MB | +0.4% | 41.471s | -13.9% | 342.060 | -9.5%
50 | 979MB | +1.2% | 37.778s | -21.6% | 311.040s | -17.7%
10 | 1.1GB | +6.6% | 32.518s | -32.5% | 279.890s | -25.9%
and for git.git:
depth | size | % | rev-list | % | log -Sfoo | %
-------+-------+-------+----------+--------+-----------+-------
250 | 48MB | n/a | 2.215s | n/a | 20.922s | n/a
100 | 49MB | +0.5% | 2.140s | -3.4% | 17.736s | -15.2%
50 | 49MB | +1.7% | 2.099s | -5.2% | 15.418s | -26.3%
10 | 53MB | +9.3% | 2.001s | -9.7% | 12.677s | -39.4%
You can see that that the CPU savings for regular operations improves as we
decrease the depth. The savings are less for "rev-list" on a smaller repository
than they are for blob-accessing operations, or even rev-list on a larger
repository. This may mean that a larger delta cache would help (though setting
core.deltaBaseCacheLimit by itself doesn't).
But we can also see that the space savings are not that great as the depth goes
higher. Saving 5-10% between 10 and 50 is probably worth the CPU tradeoff.
Saving 1% to go from 50 to 100, or another 0.5% to go from 100 to 250 is
probably not.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
