When we swapped the order of --3way fallback, we forgot to adjust
the message we give when the first method fails and the second
method is attempted (which used to be "direct application failed
hence we try 3way", now it is the other way around).
* jz/apply-3way-first-message-fix:
apply: adjust messages to account for --3way changes
When the reachability bitmap is in effect, the "do not lose
recently created objects and those that are reachable from them"
safety to protect us from races were disabled by mistake, which has
been corrected.
* jk/prune-with-bitmap-fix:
prune: save reachable-from-recent objects with bitmaps
pack-bitmap: clean up include_check after use
Tweak a few tests for "log --format=..." that show timestamps in
various formats.
* ab/pretty-date-format-tests:
pretty tests: give --date/format tests a better description
pretty tests: simplify %aI/%cI date format test
"git --config-env var=val cmd" weren't accepted (only
--config-env=var=val was).
* ps/config-env-option-with-separate-value:
git: support separate arg for `--config-env`'s value
git.txt: fix synopsis of `--config-env` missing the equals sign
Clarify that pathnames recorded in Git trees are most often (but
not necessarily) encoded in UTF-8.
* ab/pathname-encoding-doc:
doc: clarify the filename encoding in git diff
Effort to make the command line completion (in contrib/) safe with
"set -u" continues.
* vs/completion-with-set-u:
completion: avoid aliased command lookup error in nounset mode
Show errno in the trace output in the error codepath that calls
read_raw_ref method.
* hn/refs-trace-errno:
refs: print errno for read_raw_ref if GIT_TRACE_REFS is set
The checkout machinery has been taught to perform the actual
write-out of the files in parallel when able.
* mt/parallel-checkout-part-2:
parallel-checkout: add design documentation
parallel-checkout: support progress displaying
parallel-checkout: add configuration options
parallel-checkout: make it truly parallel
unpack-trees: add basic support for parallel checkout
Builds on top of the sparse-index infrastructure to mark operations
that are not ready to mark with the sparse index, causing them to
fall back on fully-populated index that they always have worked with.
* ds/sparse-index-protections: (47 commits)
name-hash: use expand_to_path()
sparse-index: expand_to_path()
name-hash: don't add directories to name_hash
revision: ensure full index
resolve-undo: ensure full index
read-cache: ensure full index
pathspec: ensure full index
merge-recursive: ensure full index
entry: ensure full index
dir: ensure full index
update-index: ensure full index
stash: ensure full index
rm: ensure full index
merge-index: ensure full index
ls-files: ensure full index
grep: ensure full index
fsck: ensure full index
difftool: ensure full index
commit: ensure full index
checkout: ensure full index
...
The prefetch task in "git maintenance" assumed that "git fetch"
from any remote would fetch all its local branches, which would
fetch too much if the user is interested in only a subset of
branches there.
* ds/maintenance-prefetch-fix:
maintenance: respect remote.*.skipFetchAll
maintenance: use 'git fetch --prefetch'
fetch: add --prefetch option
maintenance: simplify prefetch logic
"git push --quiet --set-upstream" was not quiet when setting the
upstream branch configuration, which has been corrected.
* ow/push-quiet-set-upstream:
transport: respect verbosity when setting upstream
When packet_write() fails, we gave an extra error message
unnecessarily, which has been corrected.
* mt/pkt-write-errors:
pkt-line: do not report packet write errors twice
Handling of "promisor packs" that allows certain objects to be
missing and lazily retrievable has been optimized (a bit).
* jk/promisor-optim:
revision: avoid parsing with --exclude-promisor-objects
lookup_unknown_object(): take a repository argument
is_promisor_object(): free tree buffer after parsing
While not documented as such, many of the top-level options like
`--git-dir` and `--work-tree` support two syntaxes: they accept both an
equals sign between option and its value, and they do support option and
value as two separate arguments. The recently added `--config-env`
option only supports the syntax with an equals sign.
Mitigate this inconsistency by accepting both syntaxes and add tests to
verify both work.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When executing `git -h`, then the `--config-env` documentation rightly
lists the option as requiring an equals between the option and its
argument: this is the only currently supported format. But the git(1)
manpage incorrectly lists the option as taking a space in between.
Fix the issue by adding the missing space.
Reported-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-of-by: Patrick Steinhardt <ps@pks.im>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git apply" specifically calls out when it is falling back to 3way
merge application. Since the order changed to preferring 3way and
falling back to direct application, continue that behavior by
printing whenever 3way fails and git has to fall back.
Signed-off-by: Jerry Zhang <jerry@skydio.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We pass our prune expiration to mark_reachable_objects(), which will
traverse not only the reachable objects, but consider any recent ones as
tips for reachability; see d3038d22f9 (prune: keep objects reachable
from recent objects, 2014-10-15) for details.
However, this interacts badly with the bitmap code path added in
fde67d6896 (prune: use bitmaps for reachability traversal, 2019-02-13).
If we hit the bitmap-optimized path, we return immediately to avoid the
regular traversal, accidentally skipping the "also traverse recent"
code.
Instead, we should do an if-else for the bitmap versus regular
traversal, and then follow up with the "recent" traversal in either
case. This reuses the "rev_info" for a bitmap and then a regular
traversal, but that should work OK (the bitmap code clears the pending
array in the usual way, just like a regular traversal would).
Note that I dropped the comment above the regular traversal here. It
has little explanatory value, and makes the if-else logic much harder to
read.
Here are a few variants that I rejected:
- it seems like both the reachability and recent traversals could be
done in a single traversal. This was rejected by d3038d22f9 (prune:
keep objects reachable from recent objects, 2014-10-15), though the
balance may be different when using bitmaps. However, there's a
subtle correctness issue, too: we use revs->ignore_missing_links for
the recent traversal, but not the reachability one.
- we could try using bitmaps for the recent traversal, too, which
could possibly improve performance. But it would require some fixes
in the bitmap code, which uses ignore_missing_links for its own
purposes. Plus it would probably not help all that much in practice.
We use the reachable tips to generate bitmaps, so those objects are
likely not covered by bitmaps (unless they just became unreachable).
And in general, we expect the set of unreachable objects to be much
smaller anyway, so there's less to gain.
The test in t5304 detects the bug and confirms the fix.
I also beefed up the tests in t6501, which covers the mtime-checking
code more thoroughly, to handle the bitmap case (in addition to just
"loose" and "packed" cases). Interestingly, this test doesn't actually
detect the bug, because it is running "git gc", and not "prune"
directly. And "gc" will call "repack" first, which does not suffer the
same bug. So the old-but-reachable-from-recent objects get scooped up
into the new pack along with the actually-recent objects, which gives
both a recent mtime. But it seemed prudent to get more coverage of the
bitmap case for related code.
Reported-by: David Emett <dave@sp4m.net>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When a bitmap walk has to traverse (to fill in non-bitmapped objects),
we use rev_info's include_check mechanism to let us stop the traversal
early. But after setting the function and its data parameter, we never
clean it up. This means that if the rev_info is used for a subsequent
traversal without bitmaps, it will unexpectedly call into our
include_check function (worse, it will do so pointing to a now-defunct
stack variable in include_check_data, likely resulting in a segfault).
There's no code which does this now, but it's an accident waiting to
happen. Let's clean up after ourselves in the bitmap code.
Reported-by: David Emett <dave@sp4m.net>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
From the documentation for generating patch text with diff-related
commands, refer to the documentation for the diff attribute.
This attribute influences the way that patches are generated, but this
was previously not mentioned in e.g., the git-diff manpage.
Signed-off-by: Peter Oliver <git@mavit.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the description for the --date/format equivalency tests added
in 466fb6742d (pretty: provide a strict ISO 8601 date format,
2014-08-29) and 0df621172d (pretty: provide short date format,
2019-11-19) to be more meaningful.
This allows us to reword the comment added in the former commit to
refer to both tests, and any other future test, such as the in-flight
--date=human format being proposed in [1].
1. http://lore.kernel.org/git/pull.939.v2.git.1619275340051.gitgitgadget@gmail.com
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change a needlessly complex test for the %aI/%cI date
formats (iso-strict) added in 466fb6742d (pretty: provide a strict
ISO 8601 date format, 2014-08-29) to instead use the same pattern used
to test %as/%cs since 0df621172d (pretty: provide short date format,
2019-11-19).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The dependencies for config-list.h and command-list.h were broken
when the former was split out of the latter, which has been
corrected.
* sg/bugreport-fixes:
Makefile: add missing dependencies of 'config-list.h'
Documentation updates, with unrelated comment updates, too.
* ab/usage-error-docs:
api docs: document that BUG() emits a trace2 error event
api docs: document BUG() in api-error-handling.txt
usage.c: don't copy/paste the same comment three times
When "git pack-objects" makes a literal copy of a part of existing
packfile using the reachability bitmaps, its update to the progress
meter was broken.
* jk/pack-objects-bitmap-progress-fix:
pack-objects: update "nr_seen" progress based on pack-reused count
A bit of code clean-up and a lot of test clean-up around userdiff
area.
* ab/userdiff-tests:
blame tests: simplify userdiff driver test
blame tests: don't rely on t/t4018/ directory
userdiff: remove support for "broken" tests
userdiff tests: list builtin drivers via test-tool
userdiff tests: explicitly test "default" pattern
userdiff: add and use for_each_userdiff_driver()
userdiff style: normalize pascal regex declaration
userdiff style: declare patterns with consistent style
userdiff style: re-order drivers in alphabetical order
AFAICT parsing the output of `git diff --name-only master...feature`
is the intended way of programmatically getting the list of files
modified
by a feature branch. It is impossible to parse text unless you know what
encoding it is in. The output encoding of diff --name-only and
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Co-authored-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Make parallel checkout configurable by introducing two new settings:
checkout.workers and checkout.thresholdForParallelism. The first defines
the number of workers (where one means sequential checkout), and the
second defines the minimum number of entries to attempt parallel
checkout.
To decide the default value for checkout.workers, the parallel version
was benchmarked during three operations in the linux repo, with cold
cache: cloning v5.8, checking out v5.8 from v2.6.15 (checkout I) and
checking out v5.8 from v5.7 (checkout II). The four tables below show
the mean run times and standard deviations for 5 runs in: a local file
system on SSD, a local file system on HDD, a Linux NFS server, and
Amazon EFS (all on Linux). Each parallel checkout test was executed with
the number of workers that brings the best overall results in that
environment.
Local SSD:
Sequential 10 workers Speedup
Clone 8.805 s ± 0.043 s 3.564 s ± 0.041 s 2.47 ± 0.03
Checkout I 9.678 s ± 0.057 s 4.486 s ± 0.050 s 2.16 ± 0.03
Checkout II 5.034 s ± 0.072 s 3.021 s ± 0.038 s 1.67 ± 0.03
Local HDD:
Sequential 10 workers Speedup
Clone 32.288 s ± 0.580 s 30.724 s ± 0.522 s 1.05 ± 0.03
Checkout I 54.172 s ± 7.119 s 54.429 s ± 6.738 s 1.00 ± 0.18
Checkout II 40.465 s ± 2.402 s 38.682 s ± 1.365 s 1.05 ± 0.07
Linux NFS server (v4.1, on EBS, single availability zone):
Sequential 32 workers Speedup
Clone 240.368 s ± 6.347 s 57.349 s ± 0.870 s 4.19 ± 0.13
Checkout I 242.862 s ± 2.215 s 58.700 s ± 0.904 s 4.14 ± 0.07
Checkout II 65.751 s ± 1.577 s 23.820 s ± 0.407 s 2.76 ± 0.08
EFS (v4.1, replicated over multiple availability zones):
Sequential 32 workers Speedup
Clone 922.321 s ± 2.274 s 210.453 s ± 3.412 s 4.38 ± 0.07
Checkout I 1011.300 s ± 7.346 s 297.828 s ± 0.964 s 3.40 ± 0.03
Checkout II 294.104 s ± 1.836 s 126.017 s ± 1.190 s 2.33 ± 0.03
The above benchmarks show that parallel checkout is most effective on
repositories located on an SSD or over a distributed file system. For
local file systems on spinning disks, and/or older machines, the
parallelism does not always bring a good performance. For this reason,
the default value for checkout.workers is one, a.k.a. sequential
checkout.
To decide the default value for checkout.thresholdForParallelism,
another benchmark was executed in the "Local SSD" setup, where parallel
checkout showed to be beneficial. This time, we compared the runtime of
a `git checkout -f`, with and without parallelism, after randomly
removing an increasing number of files from the Linux working tree. The
"sequential fallback" column below corresponds to the executions where
checkout.workers was 10 but checkout.thresholdForParallelism was equal
to the number of to-be-updated files plus one (so that we end up writing
sequentially). Each test case was sampled 15 times, and each sample had
a randomly different set of files removed. Here are the results:
sequential fallback 10 workers speedup
10 files 772.3 ms ± 12.6 ms 769.0 ms ± 13.6 ms 1.00 ± 0.02
20 files 780.5 ms ± 15.8 ms 775.2 ms ± 9.2 ms 1.01 ± 0.02
50 files 806.2 ms ± 13.8 ms 767.4 ms ± 8.5 ms 1.05 ± 0.02
100 files 833.7 ms ± 21.4 ms 750.5 ms ± 16.8 ms 1.11 ± 0.04
200 files 897.6 ms ± 30.9 ms 730.5 ms ± 14.7 ms 1.23 ± 0.05
500 files 1035.4 ms ± 48.0 ms 677.1 ms ± 22.3 ms 1.53 ± 0.09
1000 files 1244.6 ms ± 35.6 ms 654.0 ms ± 38.3 ms 1.90 ± 0.12
2000 files 1488.8 ms ± 53.4 ms 658.8 ms ± 23.8 ms 2.26 ± 0.12
From the above numbers, 100 files seems to be a reasonable default value
for the threshold setting.
Note: Up to 1000 files, we observe a drop in the execution time of the
parallel code with an increase in the number of files. This is a rather
odd behavior, but it was observed in multiple repetitions. Above 1000
files, the execution time increases according to the number of files, as
one would expect.
About the test environments: Local SSD tests were executed on an
i7-7700HQ (4 cores with hyper-threading) running Manjaro Linux. Local
HDD tests were executed on an Intel(R) Xeon(R) E3-1230 (also 4 cores
with hyper-threading), HDD Seagate Barracuda 7200.14 SATA 3.1, running
Debian. NFS and EFS tests were executed on an Amazon EC2 c5n.xlarge
instance, with 4 vCPUs. The Linux NFS server was running on a m6g.large
instance with 2 vCPUSs and a 1 TB EBS GP2 volume. Before each timing,
the linux repository was removed (or checked out back to its previous
state), and `sync && sysctl vm.drop_caches=3` was executed.
Co-authored-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use multiple worker processes to distribute the queued entries and call
write_pc_item() in parallel for them. The items are distributed
uniformly in contiguous chunks. This minimizes the chances of two
workers writing to the same directory simultaneously, which could affect
performance due to lock contention in the kernel. Work stealing (or any
other format of re-distribution) is not implemented yet.
The protocol between the main process and the workers is quite simple.
They exchange binary messages packed in pkt-line format, and use
PKT-FLUSH to mark the end of input (from both sides). The main process
starts the communication by sending N pkt-lines, each corresponding to
an item that needs to be written. These packets contain all the
necessary information to load, smudge, and write the blob associated
with each item. Then it waits for the worker to send back N pkt-lines
containing the results for each item. The resulting packet must contain:
the identification number of the item that it refers to, the status of
the operation, and the lstat() data gathered after writing the file (iff
the operation was successful).
For now, checkout always uses a hardcoded value of 2 workers, only to
demonstrate that the parallel checkout framework correctly divides and
writes the queued entries. The next patch will add user configurations
and define a more reasonable default, based on tests with the said
settings.
Co-authored-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Co-authored-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This new interface allows us to enqueue some of the entries being
checked out to later uncompress them, apply in-process filters, and
write out the files in parallel. For now, the parallel checkout
machinery is enabled by default and there is no user configuration, but
run_parallel_checkout() just writes the queued entries in sequence
(without spawning additional workers). The next patch will actually
implement the parallelism and, later, we will make it configurable.
Note that, to avoid potential data races, not all entries are eligible
for parallel checkout. Also, paths that collide on disk (e.g.
case-sensitive paths in case-insensitive file systems), are detected by
the parallel checkout code and skipped, so that they can be safely
sequentially handled later. The collision detection works like the
following:
- If the collision was at basename (e.g. 'a/b' and 'a/B'), the framework
detects it by looking for EEXIST and EISDIR errors after an
open(O_CREAT | O_EXCL) failure.
- If the collision was at dirname (e.g. 'a/b' and 'A'), it is detected
at the has_dirs_only_path() check, which is done for the leading path
of each item in the parallel checkout queue.
Both verifications rely on the fact that, before enqueueing an entry for
parallel checkout, checkout_entry() makes sure that there is no file at
the entry's path and that its leading components are all real
directories. So, any later change in these conditions indicates that
there was a collision (either between two parallel-eligible entries or
between an eligible and an ineligible one).
After all parallel-eligible entries have been processed, the collided
(and thus, skipped) entries are sequentially fed to checkout_entry()
again. This is similar to the way the current code deals with
collisions, overwriting the previously checked out entries with the
subsequent ones. The only difference is that, since we no longer create
the files in the same order that they appear on index, we are not able
to determine which of the colliding entries will survive on disk (for
the classic code, it is always the last entry).
Co-authored-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Co-authored-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Document changes in -m and --diff-merges=m semantics, as well as new
--diff-merges=on option.
Signed-off-by: Sergey Organov <sorganov@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
New log.diffMerges configuration variable sets the format that
--diff-merges=on will be using. The default is "separate".
t4013: add the following tests for log.diffMerges config:
* Test that wrong values are denied.
* Test that the value of log.diffMerges properly affects both
--diff-merges=on and -m.
t9902: fix completion tests for log.d* to match log.diffMerges.
Added documentation for log.diffMerges.
Signed-off-by: Sergey Organov <sorganov@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Let -m option (and --diff-merges=m) enable the default format instead
of "separate", to be able to tune it with log.diffMerges option.
Signed-off-by: Sergey Organov <sorganov@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Split set_diff_merges() into separate parsing and execution functions,
the former to be reused for parsing of configuration values later in
the patch series.
Signed-off-by: Sergey Organov <sorganov@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce the notion of default diff format for merges, and the option
"on" to select it. The default format is "separate" and can't yet
be changed, so effectively "on" is just a synonym for "separate"
for now. Add corresponding test to t4013.
This is in preparation for introducing log.diffMerges configuration
option that will let --diff-merges=on to be configured to any
supported format.
Signed-off-by: Sergey Organov <sorganov@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
