The TEST_OUTPUT_DIRECTORY environment variable can be used to instruct
the test suite to write test data and test results into a different
location than into "t/". The "ci/print-test-failures.sh" script does not
know to handle this environment variable though, which means that it
will search for test results in the wrong location if it was set.
Update the script to handle TEST_OUTPUT_DIRECTORY so that we can start
to set it in our CI.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
With the introduction of the ARM-based Macs the default location for
Homebrew has changed from "/usr/local" to "/opt/homebrew". We only
handle the former location though, which means that unless the user has
manually configured required search paths we won't be able to locate it.
Improve upon this by adding relevant paths to our CFLAGS and LDFLAGS as
well as detecting the location of msgfmt(1).
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In t7527, we test that the builtin fsmonitor daemon works well in
various edge cases. One of these tests is frequently failing because
events reported by the fsmonitor--daemon are missing an expected event.
This failure is essentially a race condition: we do not wait for the
daemon to flush out all events before we ask it to quit. Consequently,
it can happen that we miss some expected events.
In other testcases we counteract this race by sending a simple query to
the daemon. Quoting a comment:
We run a simple query after modifying the filesystem just to introduce
a bit of a delay so that the trace logging from the daemon has time to
get flushed to disk.
Now this workaround is not a "proper" fix as we do not wait for all
events to have been synchronized in a deterministic way. But this fix
seems to be sufficient for all the other tests to pass, so it must not
be all that bad.
Convert the failing test to do the same. While the test was previously
failing in about 50% of the test runs, I couldn't reproduce the failure
after the change anymore.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
9080a7f178 (builtin/show-ref: add new mode to check for reference
existence, 2023-10-31) added the option --exists to git-show-ref(1).
When you use this option against a ref that doesn't exist, but it is
a parent directory of an existing ref, you get the following error:
$ git show-ref --exists refs/heads
error: failed to look up reference: Is a directory
when the ref-files backend is in use. To be more clear to user,
hide the error about having found a directory. What matters to the
user is that the named ref does not exist. Instead, print the same
error as when the ref was not found:
error: reference does not exist
Signed-off-by: Toon Claes <toon@iotcl.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The 'check-name' subcommand to 'test-tool submodule' is documented as being
able to take a command line argument '<name>'. However, this does not work -
and has never worked - because 'argc > 0' triggers the usage message in
'cmd__submodule_check_name()'. To simplify the helper and avoid future
confusion around proper use of the subcommand, remove any references to
command line arguments for 'check-name' in usage strings and handling in
'check_name()'.
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move 'check_submodule_url' out of 'fsck.c' and into 'submodule-config.h' as
a public method, similar to 'check_submodule_name'. With the function now
accessible outside of 'fsck', it can be used in a later commit to extend
'test-tool submodule' to check the validity of submodule URLs as it does
with names in the 'check-name' subcommand.
Other than its location, no changes are made to 'check_submodule_url' in
this patch.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The shell used when using the -x option is erroneously documented to be
the one pointed to by the $SHELL environmental variable. This was true
when rebase was implemented as a shell script but this is no longer
true.
Signed-off-by: Nikolay Borisov <nik.borisov@suse.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add tests for amending the commit to add Signed-off-by trailer. And
also to check if it does not add another trailer if one already exists.
Currently, there are tests for --signoff separately in t7501, however,
they are not tested with --amend.
Therefore, these tests belong with other similar tests of --amend in
t7501-commit-basic-functionality.
Helped-by: Phillip Wood <phillip.wood123@gmail.com>
Signed-off-by: Ghanshyam Thakkar <shyamthakkar001@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add tests for --only (-o) and --include (-i). This include testing
with or without staged changes for both -i and -o. Also to test
for committing untracked files with -i, -o and without -i/-o.
Some tests already exist in t7501 for testing --only, however,
it is only tested in combination with --amend and --allow-empty
and on to-be-born branch. The addition of these tests check, when
the pathspec is provided without using -only, that only the files
matching the pathspec get committed. This behavior is same when
we provide --only and it is checked by the tests.
(as --only is the default mode of operation when pathspec is
provided.)
As for --include, there is no prior test for checking if --include
also commits staged changes, thus add test for that. Along with
the tests also document a potential bug, in which, when provided
with -i and a pathspec that does not match any tracked path,
commit does not fail if there are staged changes. And when there
are no staged changes commit fails. However, no error is returned
to stderr in either of the cases. This is described in the TODO
comment before the relevent testcase.
And also add a test for checking incompatibilty when using -o and
-i together.
Thus, these tests belong in t7501 with other similar existing tests,
as described in the case of --only.
Helped-by: Junio C Hamano <gitster@pobox.com>
Helped-by: Christian Couder <christian.couder@gmail.com>
Signed-off-by: Ghanshyam Thakkar <shyamthakkar001@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Clearing in-core repository (happens during e.g., "git fetch
--recurse-submodules" with commit graph enabled) made in-core
commit object in an inconsistent state by discarding the necessary
data from commit-graph too early, which has been corrected.
* jk/commit-graph-slab-clear-fix:
commit-graph: retain commit slab when closing NULL commit_graph
Introduce a new extension "refstorage" so that we can mark a
repository that uses a non-default ref backend, like reftable.
* ps/refstorage-extension:
t9500: write "extensions.refstorage" into config
builtin/clone: introduce `--ref-format=` value flag
builtin/init: introduce `--ref-format=` value flag
builtin/rev-parse: introduce `--show-ref-format` flag
t: introduce GIT_TEST_DEFAULT_REF_FORMAT envvar
setup: introduce GIT_DEFAULT_REF_FORMAT envvar
setup: introduce "extensions.refStorage" extension
setup: set repository's formats on init
setup: start tracking ref storage format
refs: refactor logic to look up storage backends
worktree: skip reading HEAD when repairing worktrees
t: introduce DEFAULT_REPO_FORMAT prereq
More fixes and optimizations to the reftable backend.
* ps/reftable-fixes-and-optims:
reftable/merged: transfer ownership of records when iterating
reftable/merged: really reuse buffers to compute record keys
reftable/record: store "val2" hashes as static arrays
reftable/record: store "val1" hashes as static arrays
reftable/record: constify some parts of the interface
reftable/writer: fix index corruption when writing multiple indices
reftable/stack: do not auto-compact twice in `reftable_stack_add()`
reftable/stack: do not overwrite errors when compacting
The `__git_pseudoref_exists ()` helper function back to git-rev-parse(1)
in case the reftable backend is in use. This is not in the same spirit
as the simple existence check that the "files" backend does though,
because there we only check for the pseudo-ref to exist with `test -f`.
With git-rev-parse(1) we not only check for existence, but also verify
that the pseudo-ref resolves to an object, which may not be the case
when the pseudo-ref points to an unborn branch.
Fix this issue by using `git show-ref --exists` instead. Note that we do
not have to silence stdout anymore as git-show-ref(1) will not print
anything.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 44dbb3bf29 (completion: support pseudoref existence checks for
reftables, 2023-12-19), we have extended the Bash completion script to
support future ref backends better by using git-rev-parse(1) to check
for pseudo-ref existence. This conversion has introduced a bug, because
even though we pass `--quiet` to git-rev-parse(1) it would still output
the resolved object ID of the ref in question if it exists.
Fix this by redirecting its stdout to `/dev/null` and add a test that
catches this behaviour. Note that the test passes even without the fix
for the "files" backend because we parse pseudo refs via the filesystem
directly in that case. But the test will fail with the "reftable"
backend.
Helped-by: Jeff King <peff@peff.net>
Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Improve the existence check along the following lines:
- Stop stripping the "ref :" prefix and compare to the expected value
directly. This allows us to drop a now-unused variable that was
previously leaking into the user's shell.
- Mark the "head" variable as local so that we don't leak its value
into the user's shell.
- Stop manually handling the `-C $__git_repo_path` option, which the
`__git ()` wrapper aleady does for us.
- In simlar spirit, stop redirecting stderr, which is also handled by
the wrapper already.
Suggested-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The Bash completion script must not print anything to either stdout or
stderr. Instead, it is only expected to populate certain variables.
Tighten our `test_completion ()` test helper to verify this requirement.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The helper function `__git_pseudoref_exists ()` expects that the repo
path has already been discovered by its callers, which makes for a
rather fragile calling convention. Refactor the function to discover the
repo path itself to make it more self-contained, which also removes the
need to discover the path in some of its callers.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
'--filter=blob:limit=<n>' was introduced in 25ec7bcac0 (list-objects:
filter objects in traverse_commit_list, 2017-11-21) and later expanded
to bitmaps in 84243da129 (pack-bitmap: implement BLOB_LIMIT filtering,
2020-02-14)
The logic that was introduced in these commits (and that still persists
to this day) omits blobs larger than _or equal_ to n bytes or units.
However, the documentation (Documentation/rev-list-options.txt) states:
>The form '--filter=blob:limit=<n>[kmg]' omits blobs larger than n
bytes or units. n may be zero.
Moreover, the t6113-rev-list-bitmap-filters.sh tests for exactly this
logic, so it seems it is the documentation that needs fixing, not the
code.
This changes the explanation to be similar to
Documentation/git-clone.txt, which is correct.
Signed-off-by: Nikolay Edigaryev <edigaryev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the recent codebase update (8bf6fbd00d (Merge branch
'js/doc-unit-tests', 2023-12-09)), a new unit testing framework was
merged, providing a standardized approach for testing C code. Prior to
this update, some unit tests relied on the test helper mechanism,
lacking a dedicated unit testing framework. It's more natural to perform
these unit tests using the new unit test framework.
This commit migrates the unit tests for C character classification
functions (isdigit(), isspace(), etc) from the legacy approach
using the test-tool command `test-tool ctype` in t/helper/test-ctype.c
to the new unit testing framework (t/unit-tests/test-lib.h).
The migration involves refactoring the tests to utilize the testing
macros provided by the framework (TEST() and check_*()).
Mentored-by: Christian Couder <chriscool@tuxfamily.org>
Helped-by: René Scharfe <l.s.r@web.de>
Helped-by: Phillip Wood <phillip.wood123@gmail.com>
Helped-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Achu Luma <ach.lumap@gmail.com>
Acked-by: Phillip Wood <phillip.wood123@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When `write_commit_graph()` bails out writing a split commit-graph early
then it may happen that we have already gathered the set of existing
commit-graph file names without yet determining the new merged set of
files. This can result in a memory leak though because we only clear the
preimage of files when we have collected the postimage.
Fix this issue by dropping the condition altogether so that we always
try to free both preimage and postimage filenames. As the context
structure is zero-initialized this simplification is safe to do.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Acked-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Unlike other environment variables that took the usual
true/false/yes/no as well as 0/1, GIT_FLUSH only understood 0/1,
which has been corrected.
* cp/git-flush-is-an-env-bool:
write-or-die: make GIT_FLUSH a Boolean environment variable
Sideband demultiplexer fixes.
* jx/sideband-chomp-newline-fix:
pkt-line: do not chomp newlines for sideband messages
pkt-line: memorize sideband fragment in reader
test-pkt-line: add option parser for unpack-sideband
Streaming spans of packfile data used to be done only from a
single, primary, pack in a repository with multiple packfiles. It
has been extended to allow reuse from other packfiles, too.
* tb/multi-pack-verbatim-reuse: (26 commits)
t/perf: add performance tests for multi-pack reuse
pack-bitmap: enable reuse from all bitmapped packs
pack-objects: allow setting `pack.allowPackReuse` to "single"
t/test-lib-functions.sh: implement `test_trace2_data` helper
pack-objects: add tracing for various packfile metrics
pack-bitmap: prepare to mark objects from multiple packs for reuse
pack-revindex: implement `midx_pair_to_pack_pos()`
pack-revindex: factor out `midx_key_to_pack_pos()` helper
midx: implement `midx_preferred_pack()`
git-compat-util.h: implement checked size_t to uint32_t conversion
pack-objects: include number of packs reused in output
pack-objects: prepare `write_reused_pack_verbatim()` for multi-pack reuse
pack-objects: prepare `write_reused_pack()` for multi-pack reuse
pack-objects: pass `bitmapped_pack`'s to pack-reuse functions
pack-objects: keep track of `pack_start` for each reuse pack
pack-objects: parameterize pack-reuse routines over a single pack
pack-bitmap: return multiple packs via `reuse_partial_packfile_from_bitmap()`
pack-bitmap: simplify `reuse_partial_packfile_from_bitmap()` signature
ewah: implement `bitmap_is_empty()`
pack-bitmap: pass `bitmapped_pack` struct to pack-reuse functions
...
The builtin_objectmode attribute is populated for each path
without adding anything in .gitattributes files, which would be
useful in magic pathspec, e.g., ":(attr:builtin_objectmode=100755)"
to limit to executables.
* jw/builtin-objectmode-attr:
attr: add builtin objectmode values support
Doc update.
* js/contributor-docs-updates:
SubmittingPatches: hyphenate non-ASCII
SubmittingPatches: clarify GitHub artifact format
SubmittingPatches: clarify GitHub visual
SubmittingPatches: provide tag naming advice
SubmittingPatches: update extra tags list
SubmittingPatches: discourage new trailers
SubmittingPatches: drop ref to "What's in git.git"
CodingGuidelines: write punctuation marks
CodingGuidelines: move period inside parentheses
In d70a9eb611 (strvec: rename struct fields, 2020-07-28), we renamed the
"argv" member to "v". In the same patch we also did the following rename
in strvec.c:
-void strvec_pushv(struct strvec *array, const char **argv)
+void strvec_pushv(struct strvec *array, const char **items)
and it appears that this s/argv/items operation was erroneously applied
to strvec.h.
Rename "items" to "v".
Signed-off-by: Linus Arver <linusa@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The treewide clean-up of "up-to-date" strings done in 7560f547
(treewide: correct several "up-to-date" to "up to date", 2017-08-23)
deliberately left some out, but unlike the lines that were changed
by the commit, the lines that were deliberately left untouched by
the commit is impossible to ask "git blame" to link back to the
commit that did not touch them.
Let's do the second best thing, leave a short comment near them
explaining why those strings should not be modified or localized.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
[es: make in-code comment more developer-friendly]
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To create error conditions, some tests set up reference locks by
directly creating its lockfile. While this works for the files reference
backend, this approach is incompatible with the reftable backend.
Refactor the test to create a d/f conflict via git-update-ref(1) instead
so that the test is reference backend agnostic.
Signed-off-by: Justin Tobler <jltobler@gmail.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To create error conditions, some tests set up reference locks by
directly creating its lockfile. While this works for the files reference
backend, this approach is incompatible with the reftable backend.
Refactor the test to create a d/f conflict via git-symbolic-ref(1)
instead so that the test is reference backend agnostic.
Signed-off-by: Justin Tobler <jltobler@gmail.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The error message we show when the user tries to delete a not fully
merged branch describes the error and gives a hint to the user:
error: the branch 'foo' is not fully merged.
If you are sure you want to delete it, run 'git branch -D foo'.
Let's move the hint part so that it is displayed using the advice
machinery:
error: the branch 'foo' is not fully merged
hint: If you are sure you want to delete it, run 'git branch -D foo'
hint: Disable this message with "git config advice.forceDeleteBranch false"
Signed-off-by: Rubén Justo <rjusto@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This space was introduced, presumably unintentionally, in b3b18d1621
(advice: revamp advise API, 2020-03-02)
I notice this space due to confuse diff outputs while doing some
changes to enum advice_type.
As a reference, a recent change we have to that enum is:
$ git show 35f0383
...
diff --git a/advice.h b/advice.h
index 0f584163f5..2affbe1426 100644
--- a/advice.h
+++ b/advice.h
@@ -49,6 +49,7 @@ struct string_list;
ADVICE_UPDATE_SPARSE_PATH,
ADVICE_WAITING_FOR_EDITOR,
ADVICE_SKIPPED_CHERRY_PICKS,
+ ADVICE_WORKTREE_ADD_ORPHAN,
};
Note the hunk header, instead of a much more expected:
@@ -49,6 +49,7 @@ enum advice_type
Signed-off-by: Rubén Justo <rjusto@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Let's keep the advice related lists sorted to make them more
digestible.
A multi-line comment has also been changed; that produces the unexpected
'insertion != deletion' in this supposedly 'only sort lines' commit.
Signed-off-by: Rubén Justo <rjusto@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The git-p4 tool creates a bunch of temporary branches that share a
common prefix "refs/git-p4-tmp/". These branches get cleaned up via
git-update-ref(1) after the import has finished. Once done, we try to
manually remove the now supposedly-empty ".git/refs/git-p4-tmp/"
directory.
This last step can fail in case there still are any temporary branches
around that we failed to delete because `os.rmdir()` refuses to delete a
non-empty directory. It can thus be seen as kind of a sanity check to
verify that we really did delete all temporary branches. Another failure
mode though is when the directory didn't exist in the first place, which
can be the case when using an alternate ref backend like the upcoming
"reftable" backend.
Convert the code to instead use git-for-each-ref(1) to verify that there
are no more temporary branches around. This works alright with alternate
ref backends while retaining the sanity check that we really did prune
all temporary branches.
This is a modification in behaviour for the "files" backend because the
empty directory does not get deleted anymore. But arguably we should not
care about such implementation details of the ref backend anyway, and
this should not cause any user-visible change in behaviour.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The blocksource interface provides an interface to read blocks from a
reftable table. This interface is implemented using read(3P) calls on
the underlying file descriptor. While this works alright, this pattern
is very inefficient when repeatedly querying the reftable stack for one
or more refs. This inefficiency can mostly be attributed to the fact
that we often need to re-read the same blocks over and over again, and
every single time we need to call read(3P) again.
A natural fit in this context is to use mmap(3P) instead of read(3P),
which has a bunch of benefits:
- We do not need to come up with a caching strategy for some of the
blocks as this will be handled by the kernel already.
- We can avoid the overhead of having to call into the read(3P)
syscall repeatedly.
- We do not need to allocate returned blocks repeatedly, but can
instead hand out pointers into the mmapped region directly.
Using mmap comes with a significant drawback on Windows though, because
mmapped files cannot be deleted and neither is it possible to rename
files onto an mmapped file. But for one, the reftable library gracefully
handles the case where auto-compaction cannot delete a still-open stack
already and ignores any such errors. Also, `reftable_stack_clean()` will
prune stale tables which are not referenced by "tables.list" anymore so
that those files can eventually be pruned. And second, we never rewrite
already-written stacks, so it does not matter that we cannot rename a
file over an mmaped file, either.
Another unfortunate property of mmap is that it is not supported by all
systems. But given that the size of reftables should typically be rather
limited (megabytes at most in the vast majority of repositories), we can
use the fallback implementation provided by `git_mmap()` which reads the
whole file into memory instead. This is the same strategy that the
"packed" backend uses.
While this change doesn't significantly improve performance in the case
where we're seeking through stacks once (like e.g. git-for-each-ref(1)
would). But it does speed up usecases where there is lots of random
access to refs, e.g. when writing. The following benchmark demonstrates
these savings with git-update-ref(1) creating N refs in an otherwise
empty repository:
Benchmark 1: update-ref: create many refs (refcount = 1, revision = HEAD~)
Time (mean ± σ): 5.1 ms ± 0.2 ms [User: 2.5 ms, System: 2.5 ms]
Range (min … max): 4.8 ms … 7.1 ms 111 runs
Benchmark 2: update-ref: create many refs (refcount = 100, revision = HEAD~)
Time (mean ± σ): 14.8 ms ± 0.5 ms [User: 7.1 ms, System: 7.5 ms]
Range (min … max): 14.1 ms … 18.7 ms 84 runs
Benchmark 3: update-ref: create many refs (refcount = 10000, revision = HEAD~)
Time (mean ± σ): 926.4 ms ± 5.6 ms [User: 448.5 ms, System: 477.7 ms]
Range (min … max): 920.0 ms … 936.1 ms 10 runs
Benchmark 4: update-ref: create many refs (refcount = 1, revision = HEAD)
Time (mean ± σ): 5.0 ms ± 0.2 ms [User: 2.4 ms, System: 2.5 ms]
Range (min … max): 4.7 ms … 5.4 ms 111 runs
Benchmark 5: update-ref: create many refs (refcount = 100, revision = HEAD)
Time (mean ± σ): 10.5 ms ± 0.2 ms [User: 5.0 ms, System: 5.3 ms]
Range (min … max): 10.0 ms … 10.9 ms 93 runs
Benchmark 6: update-ref: create many refs (refcount = 10000, revision = HEAD)
Time (mean ± σ): 529.6 ms ± 9.1 ms [User: 268.0 ms, System: 261.4 ms]
Range (min … max): 522.4 ms … 547.1 ms 10 runs
Summary
update-ref: create many refs (refcount = 1, revision = HEAD) ran
1.01 ± 0.06 times faster than update-ref: create many refs (refcount = 1, revision = HEAD~)
2.08 ± 0.07 times faster than update-ref: create many refs (refcount = 100, revision = HEAD)
2.95 ± 0.14 times faster than update-ref: create many refs (refcount = 100, revision = HEAD~)
105.33 ± 3.76 times faster than update-ref: create many refs (refcount = 10000, revision = HEAD)
184.24 ± 5.89 times faster than update-ref: create many refs (refcount = 10000, revision = HEAD~)
Theoretically, we could also replicate the strategy of the "packed"
backend where small tables are read into memory instead of using mmap.
Benchmarks did not confirm that this has a performance benefit though.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Refactor `reftable_block_source_from_file()` to match our coding style
better.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Whenever we call into the refs interfaces we potentially have to reload
refs in case they have been concurrently modified, either in-process or
externally. While this happens somewhat automatically for loose refs
because we simply try to re-read the files, the "packed" backend will
reload its snapshot of the packed-refs file in case its stat info has
changed since last reading it.
In the reftable backend we have a similar mechanism that is provided by
`reftable_stack_reload()`. This function will read the list of stacks
from "tables.list" and, if they have changed from the currently stored
list, reload the stacks. This is heavily inefficient though, as we have
to check whether the stack is up-to-date on basically every read and
thus keep on re-reading the file all the time even if it didn't change
at all.
We can do better and use the same stat(3P)-based mechanism that the
"packed" backend uses. Instead of reading the file, we will only open
the file descriptor, fstat(3P) it, and then compare the info against the
cached value from the last time we have updated the stack. This should
always work alright because "tables.list" is updated atomically via a
rename, so even if the ctime or mtime wasn't granular enough to identify
a change, at least the inode number or file size should have changed.
This change significantly speeds up operations where many refs are read,
like when using git-update-ref(1). The following benchmark creates N
refs in an otherwise-empty repository via `git update-ref --stdin`:
Benchmark 1: update-ref: create many refs (refcount = 1, revision = HEAD~)
Time (mean ± σ): 5.1 ms ± 0.2 ms [User: 2.4 ms, System: 2.6 ms]
Range (min … max): 4.8 ms … 7.2 ms 109 runs
Benchmark 2: update-ref: create many refs (refcount = 100, revision = HEAD~)
Time (mean ± σ): 19.1 ms ± 0.9 ms [User: 8.9 ms, System: 9.9 ms]
Range (min … max): 18.4 ms … 26.7 ms 72 runs
Benchmark 3: update-ref: create many refs (refcount = 10000, revision = HEAD~)
Time (mean ± σ): 1.336 s ± 0.018 s [User: 0.590 s, System: 0.724 s]
Range (min … max): 1.314 s … 1.373 s 10 runs
Benchmark 4: update-ref: create many refs (refcount = 1, revision = HEAD)
Time (mean ± σ): 5.1 ms ± 0.2 ms [User: 2.4 ms, System: 2.6 ms]
Range (min … max): 4.8 ms … 7.2 ms 109 runs
Benchmark 5: update-ref: create many refs (refcount = 100, revision = HEAD)
Time (mean ± σ): 14.8 ms ± 0.2 ms [User: 7.1 ms, System: 7.5 ms]
Range (min … max): 14.2 ms … 15.2 ms 82 runs
Benchmark 6: update-ref: create many refs (refcount = 10000, revision = HEAD)
Time (mean ± σ): 927.6 ms ± 5.3 ms [User: 437.8 ms, System: 489.5 ms]
Range (min … max): 919.4 ms … 936.4 ms 10 runs
Summary
update-ref: create many refs (refcount = 1, revision = HEAD) ran
1.00 ± 0.07 times faster than update-ref: create many refs (refcount = 1, revision = HEAD~)
2.89 ± 0.14 times faster than update-ref: create many refs (refcount = 100, revision = HEAD)
3.74 ± 0.25 times faster than update-ref: create many refs (refcount = 100, revision = HEAD~)
181.26 ± 8.30 times faster than update-ref: create many refs (refcount = 10000, revision = HEAD)
261.01 ± 12.35 times faster than update-ref: create many refs (refcount = 10000, revision = HEAD~)
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We're about to introduce a stat(3P)-based caching mechanism to reload
the list of stacks only when it has changed. In order to avoid race
conditions this requires us to have a file descriptor available that we
can use to call fstat(3P) on.
Prepare for this by converting the code to use `fd_read_lines()` so that
we have the file descriptor readily available.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `reftable_stack_reload_maybe_reuse()` function is responsible for
reloading the reftable list from disk. The function is quite hard to
follow though because it has a bunch of different exit paths, many of
which have to free the same set of resources.
Refactor the function to have a common exit path. While at it, touch up
the style of this function a bit to match our usual coding style better.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix a possibility of a permission to access error go unnoticed.
Perl uses two different variables to manage errors from a "do
$filename" construct. One is $@, which is set in this case when do
is unable to compile the file. The other is $!, which is set in case
do cannot read the file. The current code only checks "$@", which
means a configuration file passed to GitWeb that is not readable by
the server process does not cause it to "die".
Make sure we also check and act on "$!" to fix this.
Signed-off-by: Marcelo Roberto Jimenez <marcelo.jimenez@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is more correct because the <path>... doc syntax already indicates
that the arg is "array-type". It's how other tools do it. Finally, the
later document text mentions 'path' arguments, while it doesn't mention
'paths'.
Signed-off-by: Britton Leo Kerin <britton.kergin@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Piping the output of git commands like git-ls-files to another
command (grep in this case) hides the exit code returned by
these commands. Prevent this by storing the output of git-ls-files
to a temporary file and then "grep-ping" from that file. Replace
grep with test_grep as the latter is more verbose when it fails.
Signed-off-by: Chandra Pratap <chandrapratap3519@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>