A few days ago Travis CI updated their existing OSX images, including
the Homebrew database in the xcode10.1 OSX image that we use. Since
then installing dependencies in the 'osx-gcc' job fails when it tries
to link gcc@8:
+ brew link gcc@8
Error: No such keg: /usr/local/Cellar/gcc@8
GCC8 is still installed but not linked to '/usr/local' in the updated
image, as it was before this update, but now we have to link it by
running 'brew link gcc'. So let's do that then, and fall back to
linking gcc@8 if it doesn't, just to be sure.
Our builds on Azure Pipelines are unaffected by this issue. The OSX
image over there doesn't contain the gcc@8 package, so we have to
'brew install' it, which already takes care of linking it to
'/usr/local'. After that the 'brew link gcc' command added by this
patch fails, but the ||-chained fallback 'brew link gcc@8' command
succeeds with an "already linked" warning.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The Azure Pipelines builds are failing for macOS due to a change in the
location of the perforce cask. The command outputs the following error:
+ brew install caskroom/cask/perforce
Error: caskroom/cask was moved. Tap homebrew/cask-cask instead.
So let's try to call `brew cask install perforce` first (which is what
that error message suggests, in a most round-about way).
Prior to 672f51cb we used to install the 'perforce' package with 'brew
install perforce' (note: no 'cask' in there). The justification for
672f51cb was that the command 'brew install perforce' simply stopped
working, after Homebrew folks decided that it's better to move the
'perforce' package to a "cask". Their justification for this move was
that 'brew install perforce' "can fail due to a checksum mismatch ...",
and casks can be installed without checksum verification. And indeed,
both 'brew cask install perforce' and 'brew install
caskroom/cask/perforce' printed something along the lines of:
==> No checksum defined for Cask perforce, skipping verification
It is unclear why 672f51cb used 'brew install caskroom/cask/perforce'
instead of 'brew cask install perforce'. It appears (by running both
commands on old Travis CI macOS images) that both commands worked all
the same already back then.
In any case, as the error message at the top of this commit message
shows, 'brew install caskroom/cask/perforce' has stopped working
recently, but 'brew cask install perforce' still does, so let's use
that.
CI servers are typically fresh virtual machines, but not always. To
accommodate for that, let's try harder if `brew cask install perforce`
fails, by specifically pulling the latest `master` of the
`homebrew-cask` repository.
This will still fail, of course, when `homebrew-cask` falls behind
Perforce's release schedule. But once it is updated, we can now simply
re-run the failed jobs and they will pick up that update.
As for updating `homebrew-cask`: the beginnings of automating this in
https://dev.azure.com/gitgitgadget/git/_build?definitionId=11&_a=summary
will be finished once the next Perforce upgrade comes around.
Helped-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Dev support.
* dl/honor-cflags-in-hdr-check:
ci: run `hdr-check` as part of the `Static Analysis` job
Makefile: emulate compile in $(HCO) target better
pack-bitmap.h: remove magic number
promisor-remote.h: include missing header
apply.h: include missing header
Start using DocBook 5 (instead of DocBook 4.5) as Asciidoctor 2.0
no longer works with the older one.
* bc/doc-use-docbook-5:
Documentation: fix build with Asciidoctor 2
Travis CI offers shell access to its virtual machine environment
running the build jobs, called "debug mode" [1]. After restarting a
build job in debug mode and logging in, the first thing I usually do
is to install dependencies, i.e. run './ci/install-dependencies.sh'.
This works just fine when I restarted a failed build job in debug
mode. However, after restarting a successful build job in debug mode
our CI scripts get all clever, and exit without doing anything useful,
claiming that "This commit's tree has already been built and tested
successfully" [2]. Our CI scripts are right, and we do want to skip
building and testing already known good trees in "regular" CI builds.
In debug mode, however, this is a nuisiance, because one has to delete
the cache (or at least the 'good-trees' file in the cache) to proceed.
Let's update our CI scripts, in particular the common 'ci/lib.sh', to
not skip previously successfully built and tested trees in debug mode,
so all those scripts will do what there were supposed to do even when
a successful build job was restarted in debug mode.
[1] https://docs.travis-ci.com/user/running-build-in-debug-mode/
[2] 9cc2c76f5e (travis-ci: record and skip successfully built trees,
2017-12-31)
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Our documentation toolchain has traditionally been built around DocBook
4.5. This version of DocBook is the last DTD-based version of DocBook.
In 2009, DocBook 5 was introduced using namespaces and its syntax is
expressed in RELAX NG, which is more expressive and allows a wider
variety of syntax forms.
Asciidoctor, one of the alternatives for building our documentation,
moved support for DocBook 4.5 out of core in its recent 2.0 release and
now only supports DocBook 5 in the main release. The DocBoook 4.5
converter is still available as a separate component, but this is not
available in most distro packages. This would not be a problem but for
the fact that we use xmlto, which is still stuck in the DocBook 4.5 era.
xmlto performs DTD validation as part of the build process. This is not
problematic for DocBook 4.5, which has a valid DTD, but it clearly
cannot work for DocBook 5, since no DTD can adequately express its full
syntax. In addition, even if xmlto did support RELAX NG validation,
that wouldn't be sufficient because it uses the libxml2-based xmllint to
do so, which has known problems with validating interleaves in RELAX NG.
Fortunately, there's an easy way forward: ask Asciidoctor to use its
DocBook 5 backend and tell xmlto to skip validation. Asciidoctor has
supported DocBook 5 since v0.1.4 in 2013 and xmlto has supported
skipping validation for probably longer than that.
We also need to teach xmlto how to use the namespaced DocBook XSLT
stylesheets instead of the non-namespaced ones it usually uses.
Normally these stylesheets are interchangeable, but the non-namespaced
ones have a bug that causes them not to strip whitespace automatically
from certain elements when namespaces are in use. This results in
additional whitespace at the beginning of list elements, which is
jarring and unsightly.
We can do this by passing a custom stylesheet with the -x option that
simply imports the namespaced stylesheets via a URL. Any system with
support for XML catalogs will automatically look this URL up and
reference a local copy instead without us having to know where this
local copy is located. We know that anyone using xmlto will already
have catalogs set up properly since the DocBook 4.5 DTD used during
validation is also looked up via catalogs. All major Linux
distributions distribute the necessary stylesheets and have built-in
catalog support, and Homebrew does as well, albeit with a requirement to
set an environment variable to enable catalog support.
On the off chance that someone lacks support for catalogs, it is
possible for xmlto (via xmllint) to download the stylesheets from the
URLs in question, although this will likely perform poorly enough to
attract attention. People still have the option of using the prebuilt
documentation that we ship, so happily this should not be an impediment.
Finally, we need to filter out some messages from other stylesheets that
occur when invoking dblatex in the CI job. This tool strips namespaces
much like the unnamespaced DocBook stylesheets and prints similar
messages. If we permit these messages to be printed to standard error,
our documentation CI job will fail because we check standard error for
unexpected output. Due to dblatex's reliance on Python 2, we may need
to revisit its use in the future, in which case this problem may go
away, but this can be delayed until a future patch.
The final message we filter is due to libxslt on modern Debian and
Ubuntu. The patch which they use to implement reproducible ID
generation also prints messages about the ID generation. While this
doesn't affect our current CI images since they use Ubuntu 16.04 which
lacks this patch, if we upgrade to Ubuntu 18.04 or a modern Debian,
these messages will appear and, like the above messages, cause a CI
failure.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Once upon a time GIT_TEST_HTTPD was a tristate variable and we
exported 'GIT_TEST_HTTPD=YesPlease' in our CI scripts to make sure
that we run the httpd tests in the Linux Clang and GCC build jobs, or
error out if they can't be run for any reason [1].
Then 3b072c577b (tests: replace test_tristate with "git env--helper",
2019-06-21) came along, turned GIT_TEST_HTTPD into a bool, but forgot
to update our CI scripts accordingly. So, since GIT_TEST_HTTPD is set
explicitly, but its value is not one of the standardized true values,
our CI jobs have been simply skipping the httpd tests in the last
couple of weeks.
Set 'GIT_TEST_HTTPD=true' to restore running httpd tests in our CI
jobs.
[1] a1157b76eb (travis-ci: set GIT_TEST_HTTPD in 'ci/lib-travisci.sh',
2017-12-12)
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many GIT_TEST_* environment variables control various aspects of
how our tests are run, but a few followed "non-empty is true, empty
or unset is false" while others followed the usual "there are a few
ways to spell true, like yes, on, etc., and also ways to spell
false, like no, off, etc." convention.
* ab/test-env:
env--helper: mark a file-local symbol as static
tests: make GIT_TEST_FAIL_PREREQS a boolean
tests: replace test_tristate with "git env--helper"
tests README: re-flow a previously changed paragraph
tests: make GIT_TEST_GETTEXT_POISON a boolean
t6040 test: stop using global "script" variable
config.c: refactor die_bad_number() to not call gettext() early
env--helper: new undocumented builtin wrapping git_env_*()
config tests: simplify include cycle test
C99 'for' loop initial declaration, i.e. 'for (int i = 0; i < n; i++)',
is not allowed in Git's codebase yet, to maintain compatibility with
some older compilers.
Our Travis CI builds used to catch 'for' loop initial declarations,
because the GETTEXT_POISON job has always built Git with the default
'cc', which in Travis CI's previous default Linux image (based on
Ubuntu 14.04 Trusty) is GCC 4.8, and that GCC version errors out on
this construct (not only with DEVELOPER=1, but with our default CFLAGS
as well). Alas, that's not the case anymore, becase after 14.04's EOL
Travis CI's current default Linux image is based on Ubuntu 16.04
Xenial [1] and its default 'cc' is now GCC 5.4, which, just like all
later GCC and Clang versions, simply accepts this construct, even if
we don't explicitly specify '-std=c99'.
Ideally we would adjust our CFLAGS used with DEVELOPER=1 to catch this
undesired construct already when contributors build Git on their own
machines. Unfortunately, however, there seems to be no compiler
option that would catch only this particular construct without choking
on many other things, e.g. while a later compiler with '-std=c90'
and/or '-ansi' does catch this construct, it can't build Git because
of several screenfulls of other errors.
Add the 'linux-gcc-4.8' job to Travis CI, in order to build Git with
GCC 4.8, and thus to timely catch any 'for' loop initial declarations.
To catch those it's sufficient to only build Git with GCC 4.8, so
don't run the test suite in this job, because 'make test' takes rather
long [2], and it's already run five times in other jobs, so we
wouldn't get our time's worth.
[1] The Azure Pipelines builds have been using Ubuntu 16.04 images
from the start, so I belive they never caught 'for' loop initial
declarations.
[2] On Travis CI 'make test' alone would take about 9 minutes in this
new job (without running httpd, Subversion, and P4 tests). For
comparison, starting the job and building Git with GCC 4.8 takes
only about 2 minutes.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A comment in 'ci/lib.sh' claims that the "OS X build installs the
latest available versions" of P4 and Git-LFS, but since f2f47150
("ci: don't update Homebrew", 2019-07-03) that's no longer the case,
as it will install the versions which were recorded in the image's
Homebrew database when the image was created.
Update this comment accordingly.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Lately Homebrew learned to automagically clean up information about
outdated packages during other 'brew' commands, which might be useful
for the avarage user, but is a waste of time in CI build jobs, because
the next build jobs will start from the exact same image containing
the same outdated packages anyway.
Export HOMEBREW_NO_INSTALL_CLEANUP=1 to disable this auto cleanup feature,
shaving off about 20-30s from the time needed to install dependencies
in our macOS build jobs on Travis CI.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Lately our GCC macOS build job on Travis CI has been erroring out
while installing dependencies with:
+brew link gcc@8
Error: No such keg: /usr/local/Cellar/gcc@8
The command "ci/install-dependencies.sh" failed and exited with 1 during .
Now, while gcc@8 is still pre-installed (but not linked) and would be
perfectly usable in the Travis CI macOS image we use [1], it's at
version 8.2. However, when installing dependencies we first
explicitly run 'brew update', which spends over two minutes to update
itself and information about the available packages, and it learns
about GCC 8.3. After that point gcc@8 exclusively refers to v8.3,
and, unfortunately, 'brew' is just too dumb to be able to do anything
with the still installed 8.2 package, and the subsequent 'brew link
gcc@8' fails. (Even 'brew uninstall gcc@8' fails with the same
error!)
Don't run 'brew update' to keep the already installed GCC 8.2 'brew
link'-able. Note that in addition we have to 'export
HOMEBREW_NO_AUTO_UPDATE=1' first, because 'brew' is so very helpful
that it would implicitly run update for us on the next 'brew install
<pkg>' otherwise.
Disabling 'brew update' has additional benefits:
- It shaves off 2-3mins from the ~4mins currently spent on
installing dependencies, and the macOS build jobs have always been
prone to exceeding the time limit on Travis CI.
- Our builds won't suddenly break because of the occasional Homebrew
breakages [2].
The drawback is that we'll be stuck with slightly older versions of
the packages that we install via Homebrew (Git-LFS 2.5.2 and Perforce
2018.1; they are currently at 2.7.2 and 2019.1, respectively). We
might want to reconsider this decision as time goes on and/or switch
to a more recent macOS image as they become available.
[1] 2000ac9fbf (travis-ci: switch to Xcode 10.1 macOS image,
2019-01-17)
[2] See e.g. a1ccaedd62 (travis-ci: make the OSX build jobs' 'brew
update' more quiet, 2019-02-02) or
https://public-inbox.org/git/20180907032002.23366-1-szeder.dev@gmail.com/T/#+u
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the GIT_TEST_GETTEXT_POISON variable from being "non-empty?" to
being a more standard boolean variable.
Since it needed to be checked in both C code and shellscript (via test
-n) it was one of the remaining shellscript-like variables. Now that
we have "env--helper" we can change that.
There's a couple of tricky edge cases that arise because we're using
git_env_bool() early, and the config-reading "env--helper".
If GIT_TEST_GETTEXT_POISON is set to an invalid value die_bad_number()
will die, but to do so it would usually call gettext(). Let's detect
the special case of GIT_TEST_GETTEXT_POISON and always emit that
message in the C locale, lest we infinitely loop.
As seen in the updated tests in t0017-env-helper.sh there's also a
caveat related to "env--helper" needing to read the config for trace2
purposes.
Since the C_LOCALE_OUTPUT prerequisite is lazy and relies on
"env--helper" we could get invalid results if we failed to read the
config (e.g. because we'd loop on includes) when combined with
e.g. "test_i18ngrep" wanting to check with "env--helper" if
GIT_TEST_GETTEXT_POISON was true or not.
I'm crossing my fingers and hoping that a test similar to the one I
removed in the earlier "config tests: simplify include cycle test"
change in this series won't happen again, and testing for this
explicitly in "env--helper"'s own tests.
This change breaks existing uses of
e.g. GIT_TEST_GETTEXT_POISON=YesPlease, which we've documented in
po/README and other places. As noted in [1] we might want to consider
also accepting "YesPlease" in "env--helper" as a special-case.
But as the lack of uproar over 6cdccfce1e ("i18n: make GETTEXT_POISON
a runtime option", 2018-11-08) demonstrates the audience for this
option is a really narrow set of git developers, who shouldn't have
much trouble modifying their test scripts, so I think it's better to
deal with that minor headache now and make all the relevant GIT_TEST_*
variables boolean in the same way than carry the "YesPlease"
special-case forward.
1. https://public-inbox.org/git/xmqqtvckm3h8.fsf@gitster-ct.c.googlers.com/
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To run tests for Git SVN, our scripts for CI used to install the
git-svn package (in the hope that it would bring in the right
dependencies). This has been updated to install the more direct
dependency, namely, libsvn-perl.
* sg/ci-libsvn-perl:
ci: install 'libsvn-perl' instead of 'git-svn'
Since e7e9f5e7a1 (travis-ci: enable Git SVN tests t91xx on Linux,
2016-05-19) some of our Travis CI build jobs install the 'git-svn'
package, because it was a convenient way to install its dependencies,
which are necessary to run our 'git-svn' tests (we don't actually need
the 'git-svn' package itself). However, from those dependencies,
namely the 'libsvn-perl', 'libyaml-perl', and 'libterm-readkey-perl'
packages, only 'libsvn-perl' is necessary to run those tests, the
others arent, not even to fulfill some prereqs.
So update 'ci/install-dependencies.sh' to install only 'libsvn-perl'
instead of 'git-svn' and its additional dependencies.
Note that this change has more important implications than merely not
installing three unnecessary packages, as it keeps our builds working
with Travis CI's Xenial images. In our '.travis.yml' we never
explicitly specified which Linux image we want to use to run our Linux
build jobs, and so far they have been run on the default Ubuntu 14.04
Trusty image. However, 14.04 just reached its EOL, and Travis CI has
already began the transition to use 16.04 Xenial as the default Linux
build environment [1]. Alas, our Linux Clang and GCC build jobs can't
simply 'apt-get install git-svn' in the current Xenial images [2],
like they did in the Trusty images, and, consequently, fail.
Installing only 'libsvn-perl' avoids this issue, while the 'git svn'
tests are still run as they should.
[1] https://blog.travis-ci.com/2019-04-15-xenial-default-build-environment
[2] 'apt-get install git-svn' in the Xenial image fails with:
The following packages have unmet dependencies:
git-svn : Depends: git (< 1:2.7.4-.)
E: Unable to correct problems, you have held broken packages.
The reason is that both the Trusty and Xenial images contain the
'git' package installed from 'ppa:git-core/ppa', so it's
considerably newer than the 'git' package in the corresponding
standard Ubuntu package repositories. The difference is that the
Trusty image still contains these third-party apt repositories, so
the 'git-svn' package was installed from the same PPA, and its
version matched the version of the already installed 'git'
package. In the Xenial image, however, these third-party
apt-repositories are removed (to reduce the risk of unrelated
interference and faster 'apt-get update') [3], and the version of
the 'git-svn' package coming from the standard Ubuntu package
repositories doesn't match the much more recent version of the
'git' package installed from the PPA, resulting in this dependecy
error.
Adding back the 'ppa:git-core/ppa' package repository would solve
this dependency issue as well, but since the troublesome package
happens to be unnecessary, not installing it in the first place is
better.
[3] https://docs.travis-ci.com/user/reference/xenial/#third-party-apt-repositories-removed
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 'ci/test-documentation.sh' we save the standard error of 'make
doc', and, in an attempt to make sure that neither AsciiDoc nor
Asciidoctor printed any warnings, we check the emptiness of the
resulting file with '! test -s stderr.log'. This check has never
actually worked, because in our 'ci/*' build scripts we rely on 'set
-e' aborting the build job when a command exits with error, and,
unfortunately, the combination of the two doesn't work as intended.
According to POSIX [1]:
"The -e setting shall be ignored when executing [...] a pipeline
beginning with the ! reserved word" [2]
Watch and learn:
$ echo unexpected >file
$ ( set -e; ! test -s file ; echo "should not reach this" ) ; echo $?
should not reach this
0
This is why we haven't noticed the warnings from Asciidoctor that were
fixed in the first patches of this patch series, though some of them
were already there in the build of v2.18.0-rc0 [3].
Check the emptiness of that file with 'test ! -s' instead, which works
properly with 'set -e':
$ ( set -e; test ! -s file ; echo "should not reach this" ) ; echo $?
1
Furthermore, dump the contents of that file to the log for our
convenience, so if it were to unexpectedly end up being non-empty,
then we wouldn't have to scroll through all that long build log
looking for warnings, but could see them right away near the end of
the log.
Note that we are only really interested in the standard error of
AsciiDoc and Asciidoctor, but by saving the stderr of 'make doc' we
also save any error output from the make rules. Currently there is
only one such line: we build the docs with Asciidoctor right after a
'make clean', meaning that 'make USE_ASCIIDOCTOR=1 doc' always starts
with running 'GIT-VERSION-GEN', which in turn prints the version to
stderr. A 'sed' command was supposed to remove this version line to
prevent it from triggering that (previously defunct) emptiness check,
but, unfortunately, this command doesn't work as intended, either,
because it leaves the file to be checked intact, but that defunct
emptiness check hid this issue, too... Furthermore, in the near
future there will be an other line on stderr, because commit
9a71722b4d (Doc: auto-detect changed build flags, 2019-03-17) in the
currently cooking branch 'ma/doc-diff-doc-vs-doctor-comparison' will
print "* new asciidoc flags" at the beginning of both 'make doc'
invokations.
Extend that 'sed' command to remove this line, too, wrap it in a
helper function so the output of both 'make doc' is filtered the same
way, and change its invokation to actually write the logfile to be
checked.
[1] http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#set
[2] POSIX doesn't discuss the meaning of '! cmd' in case of simple
commands, but it defines that "A pipeline is a sequence of one or
more commands separated by the control operator '|'", so
apparently a simple command is considered as pipeline as well.
http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_09_02
[3] https://travis-ci.org/git/git/jobs/385932007#L1463
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The recent release of Asciidoctor v2.0.0 broke our documentation
build job on Travis CI, where we 'gem install asciidoctor', which
always brings us the latest and (supposedly) greatest. Alas, we are
not ready for that just yet, because it removed support for DocBook
4.5, and we have been requiring that particular DocBook version to
build 'user-manual.xml' with Asciidoctor, resulting in:
ASCIIDOC user-manual.xml
asciidoctor: FAILED: missing converter for backend 'docbook45'. Processing aborted.
Use --trace for backtrace
make[1]: *** [user-manual.xml] Error 1
Unfortunately, we can't simply switch to DocBook 5 right away, as
doing so leads to validation errors from 'xmlto', and working around
those leads to yet another errors... [1]
So let's stick with Asciidoctor v1.5.8 (latest stable release before
v2.0.0) in our documentation build job on Travis CI for now, until we
figure out how to deal with the fallout from Asciidoctor v2.0.0.
[1] https://public-inbox.org/git/20190324162131.GL4047@pobox.com/
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When our '.travis.yml' was split into several 'ci/*' scripts [1], the
installation of the 'asciidoctor' gem somehow ended up in
'ci/test-documentation.sh'.
Install it in 'ci/install-dependencies.sh', where we install other
dependencies of the Documentation build job as well (asciidoc,
xmlto).
[1] 657343a602 (travis-ci: move Travis CI code into dedicated scripts,
2017-09-10)
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since Travis did not support Windows (and now only supports very limited
Windows jobs, too limited for our use, the test suite would time out
*all* the time), we added a hack where a Travis job would trigger an
Azure Pipeline (which back then was still called VSTS Build), wait for
it to finish (or time out), and download the log (if available).
Needless to say that it was a horrible hack, necessitated by a bad
situation.
Nowadays, however, we have Azure Pipelines support, and do not need that
hack anymore. So let's retire it.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Clearing it once upfront, and turning all the assignment into
appending, would future-proof the code even more, to prevent
mistakes the previous one fixed from happening again.
Also, mark the variable exported just once at the beginning. There
is no point in marking it exported repeatedly.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit 2c8921db2b (travis-ci: build with the right compiler,
2019-01-17) started to use MAKEFLAGS to specify which compiler to use
to build Git. A bit later, and in a different topic branch commit
eaa62291ff (ci: inherit --jobs via MAKEFLAGS in run-build-and-tests,
2019-01-27) started to use MAKEFLAGS as well. Unfortunately, there is
a semantic conflict between these two commits: both of them set
MAKEFLAGS, and since the line adding CC from 2c8921db2b comes later in
'ci/lib.sh', it overwrites the number of parallel jobs added in
eaa62291ff.
Consequently, since both commits have been merged all our CI jobs have
been building Git, building its documentation, and applying semantic
patches sequentially, making all build jobs a bit slower. Running
the test suite is unaffected, because the number of test jobs comes
from GIT_PROVE_OPTS.
Append to MAKEFLAGS when setting the compiler to use, to ensure that
the number of parallel jobs to use is preserved.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The way the OSX build jobs updates its build environment used the
"--quiet" option to "brew update" command, but it wasn't all that
quiet to be useful. The use of the option has been replaced with
an explicit redirection to the /dev/null (which incidentally would
have worked around a breakage by recent updates to homebrew, which
has fixed itself already).
* sg/travis-osx-brew-breakage-workaround:
travis-ci: make the OSX build jobs' 'brew update' more quiet
Prepare to run test suite on Azure Pipeline.
* js/vsts-ci: (22 commits)
test-date: drop unused parameter to getnanos()
ci: parallelize testing on Windows
ci: speed up Windows phase
tests: optionally skip bin-wrappers/
t0061: workaround issues with --with-dashes and RUNTIME_PREFIX
tests: add t/helper/ to the PATH with --with-dashes
mingw: try to work around issues with the test cleanup
tests: include detailed trace logs with --write-junit-xml upon failure
tests: avoid calling Perl just to determine file sizes
README: add a build badge (status of the Azure Pipelines build)
mingw: be more generous when wrapping up the setitimer() emulation
ci: use git-sdk-64-minimal build artifact
ci: add a Windows job to the Azure Pipelines definition
Add a build definition for Azure DevOps
ci/lib.sh: add support for Azure Pipelines
tests: optionally write results as JUnit-style .xml
test-date: add a subcommand to measure times in shell scripts
ci: use a junction on Windows instead of a symlink
ci: inherit --jobs via MAKEFLAGS in run-build-and-tests
ci/lib.sh: encapsulate Travis-specific things
...
Before installing the necessary dependencies, our OSX build jobs run
'brew update --quiet'. This is problematic for two reasons:
- This '--quiet' flag apparently broke overnight, resulting in
errored builds:
+brew update --quiet
==> Downloading https://homebrew.bintray.com/bottles-portable-ruby/portable-ruby-2.3.7.mavericks.bottle.tar.gz
######################################################################## 100.0%
==> Pouring portable-ruby-2.3.7.mavericks.bottle.tar.gz
Usage: brew update_report [--preinstall]
The Ruby implementation of brew update. Never called manually.
--preinstall Run in 'auto-update' mode (faster, less
output).
-f, --force Override warnings and enable potentially
unsafe operations.
-d, --debug Display any debugging information.
-v, --verbose Make some output more verbose.
-h, --help Show this message.
Error: invalid option: --quiet
The command "ci/install-dependencies.sh" failed and exited with 1 during .
I belive that this breakage will be noticed and fixed soon-ish, so
we could probably just wait a bit for this issue to solve itself,
but:
- 'brew update --quiet' wasn't really quiet in the first place, as
it listed over about 2000 lines worth of available packages that
we absolutely don't care about, see e.g. one of the latest
'master' builds:
https://travis-ci.org/git/git/jobs/486134962#L113
So drop this '--quiet' option and redirect 'brew update's standard
output to /dev/null to make it really quiet, thereby making the OSX
builds work again despite the above mentioned breakage.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The fact that Git's test suite is implemented in Unix shell script that
is as portable as we can muster, combined with the fact that Unix shell
scripting is foreign to Windows (and therefore has to be emulated),
results in pretty abysmal speed of the test suite on that platform, for
pretty much no other reason than that language choice.
For comparison: while the Linux build & test is typically done within
about 8 minutes, the Windows build & test typically lasts about 80
minutes in Azure Pipelines.
To help with that, let's use the Azure Pipeline feature where you can
parallelize jobs, make jobs depend on each other, and pass artifacts
between them.
The tests are distributed using the following heuristic: listing all
test scripts ordered by size in descending order (as a cheap way to
estimate the overall run time), every Nth script is run (where N is the
total number of parallel jobs), starting at the index corresponding to
the parallel job. This slicing is performed by a new function that is
added to the `test-tool`.
To optimize the overall runtime of the entire Pipeline, we need to move
the Windows jobs to the beginning (otherwise there would be a very
decent chance for the Pipeline to be run only the Windows build, while
all the parallel Windows test jobs wait for this single one).
We use Azure Pipelines Artifacts for both the minimal Git for Windows
SDK as well as the built executables, as deduplication and caching close
to the agents makes that really fast. For comparison: while downloading
and unpacking the minimal Git for Windows SDK via PowerShell takes only
one minute (down from anywhere between 2.5 to 7 when using a shallow
clone), uploading it as Pipeline Artifact takes less than 30s and
downloading and unpacking less than 20s (sometimes even as little as
only twelve seconds).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As Unix shell scripting comes at a hefty price on Windows, we have to
see where we can save some time to run the test suite.
Let's skip the chain linting and the bin-wrappers/ redirection on
Windows; this seems to shave of anywhere between 10-30% from the overall
runtime.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit adds an azure-pipelines.yml file which is Azure DevOps'
equivalent to Travis CI's .travis.yml.
The main idea is to replicate the Travis configuration as faithfully as
possible, to make it easy to compare the Azure Pipeline builds to the
Travis ones (spoiler: some parts, especially the macOS jobs, are way
faster in Azure Pileines). Meaning: the number and the order of the jobs
added in this commit faithfully replicates what we have in .travis.yml.
Note: Our .travis.yml configuration has a Windows part that is *not*
replicated in the Azure Pipelines definition. The reason is easy to see:
As Travis cannot support our Windws needs (even with the preliminary
Windows support that was recently added to Travis after waiting for
*years* for that feature, our test suite would simply hit Travis'
timeout every single time).
To make things a bit easier to understand, we refrain from using the
`matrix` feature here because (while it is powerful) it can be a bit
confusing to users who are not familiar with CI setups. Therefore, we
use a separate phase even for similar configurations (such as GCC vs
Clang on Linux, GCC vs Clang on macOS).
Also, we make use of the shiny new feature we just introduced where the
test suite can output JUnit-style .xml files. This information is made
available in a nice UI that allows the viewer to filter by phase and/or
test number, and to see trends such as: number of (failing) tests, time
spent running the test suite, etc. (While this seemingly contradicts the
intention to replicate the Travis configuration as faithfully as
possible, it is just too nice to show off that capability here already.)
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This patch introduces a conditional arm that defines some environment
variables and a function that displays the URL given the job id (to
identify previous runs for known-good trees).
Because Azure Pipeline's macOS agents already have git-lfs and gettext
installed, we can leave `BREW_INSTALL_PACKAGES` empty (unlike in
Travis' case).
Note: this patch does not introduce an Azure Pipelines definition yet;
That is left for the next patch.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Symbolic links are still not quite as easy to use on Windows as on Linux
(for example, on versions older than Windows 10, only administrators can
create symlinks, and on Windows 10 you still need to be in developer
mode for regular users to have permission), but NTFS junctions can give
us a way out.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Let's not decide in the generic ci/ part how many jobs to run in
parallel; different CI configurations would favor a different number of
parallel jobs, and it is easy enough to hand that information down via
the `MAKEFLAGS` variable.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The upcoming patches will allow building git.git via Azure Pipelines
(i.e. Azure DevOps' Continuous Integration), where variable names and
URLs look a bit different than in Travis CI.
Also, the configurations of the available agents are different. For
example, Travis' and Azure Pipelines' macOS agents are set up
differently, so that on Travis, we have to install the git-lfs and
gettext Homebrew packages, and on Azure Pipelines we do not need to.
Likewise, Azure Pipelines' Ubuntu agents already have asciidoctor
installed.
Finally, on Azure Pipelines the natural way is not to base64-encode tar
files of the trash directories of failed tests, but to publish build
artifacts instead. Therefore, that code to log those base64-encoded tar
files is guarded to be Travis-specific.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The name is hard-coded to reflect that we use Travis CI for continuous
testing.
In the next commits, we will extend this to be able use Azure DevOps,
too.
So let's adjust the name to make it more generic.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When building a PR, TRAVIS_BRANCH refers to the *target branch*.
Therefore, if a PR targets `master`, and `master` happened to be tagged,
we skipped the build by mistake.
Fix this by using TRAVIS_PULL_REQUEST_BRANCH (i.e. the *source branch*)
when available, falling back to TRAVIS_BRANCH (i.e. for CI builds, also
known as "push builds").
Let's give it a new variable name, too: CI_BRANCH (as it is different
from TRAVIS_BRANCH). This also prepares for the upcoming patches which
will make our ci/* code a bit more independent from Travis and open it
to other CI systems (in particular to Azure Pipelines).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Our 'Makefile' hardcodes the compiler to build Git as 'CC = cc'. This
CC variable can be overridden from the command line, i.e. 'make
CC=gcc-X.Y' will build with that particular GCC version, but not from
the environment, i.e. 'CC=gcc-X.Y make' will still build with whatever
'cc' happens to be on the platform.
Our build jobs on Travis CI are badly affected by this. In the build
matrix we have dedicated build jobs to build Git with GCC and Clang
both on Linux and macOS from the very beginning (522354d70f (Add
Travis CI support, 2015-11-27)). Alas, this never really worked as
supposed to, because Travis CI specifies the compiler for those build
jobs as 'export CC=gcc' and 'export CC=clang' (which works fine for
projects built with './configure && make'). Consequently, our
'linux-clang' build job has always used GCC, because that's where 'cc'
points at in Travis CI's Linux images, while the 'osx-gcc' build job
has always used Clang. Furthermore, 37fa4b3c78 (travis-ci: run gcc-8
on linux-gcc jobs, 2018-05-19) added an 'export CC=gcc-8' in an
attempt to build with a more modern compiler, but to no avail.
Set MAKEFLAGS with CC based on the $CC environment variable, so 'make'
will run the "right" compiler. The Xcode 10.1 macOS image on Travis
CI already contains the gcc@8 package from Homebrew, but we have to
'brew link' it first to be able to use it.
So with this patch our build jobs will build Git with the following
compiler versions:
linux-clang: clang version 5.0.0 (tags/RELEASE_500/final)
linux-gcc: gcc-8 (Ubuntu 8.1.0-5ubuntu1~14.04) 8.1.0
osx-clang: Apple LLVM version 10.0.0 (clang-1000.11.45.5)
osx-gcc: gcc-8 (Homebrew GCC 8.2.0) 8.2.0
GETTEXT_POISON: gcc (Ubuntu 4.8.4-2ubuntu1~14.04.3) 4.8.4
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
All Travis CI build jobs run the test suite with 'make --quiet test'.
On one hand, being quiet doesn't save us from much clutter in the
output:
$ make test |wc -l
861
$ make --quiet test |wc -l
848
It only spares 13 lines, mostly the output of entering the 't/'
directory and the pre- and post-cleanup commands, which is negligible
compared to the ~700 lines printed while building Git and the ~850
lines of 'prove' output.
On the other hand, it's asking for trouble. In our CI build scripts
we build Git and run the test suite in two separate 'make'
invocations. In a prelimiary version of one of the later patches in
this series, to explicitly specify which compiler to use, I changed
them to basically run:
make CC=$CC
make --quiet test
naively thinking that it should Just Work... but then that 'make
--quiet test' got all clever on me, noticed the changed build flags,
and then proceeded to rebuild everything with the default 'cc'. And
because of that '--quiet' option, it did so, well, quietly, only
saying "* new build flags", and it was by mere luck that I happened to
notice that something is amiss.
Let's just drop that '--quiet' option when running the test suite in
all build scripts.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Our testing framework uses a special i18n "poisoned localization"
feature to find messages that ought to stay constant but are
incorrectly marked to be translated. This feature has been made
into a runtime option (it used to be a compile-time option).
* ab/dynamic-gettext-poison:
Makefile: ease dynamic-gettext-poison transition
i18n: make GETTEXT_POISON a runtime option
The procedure to install dependencies before testing at Travis CI
is getting revamped for both simplicity and flexibility, taking
advantage of the recent move to the vm-based environment.
* sg/travis-install-dependencies:
travis-ci: install packages in 'ci/install-dependencies.sh'
Change the GETTEXT_POISON compile-time + runtime GIT_GETTEXT_POISON
test parameter to only be a GIT_TEST_GETTEXT_POISON=<non-empty?>
runtime parameter, to be consistent with other parameters documented
in "Running tests with special setups" in t/README.
When I added GETTEXT_POISON in bb946bba76 ("i18n: add GETTEXT_POISON
to simulate unfriendly translator", 2011-02-22) I was concerned with
ensuring that the _() function would get constant folded if NO_GETTEXT
was defined, and likewise that GETTEXT_POISON would be compiled out
unless it was defined.
But as the benchmark in my [1] shows doing a one-off runtime
getenv("GIT_TEST_[...]") is trivial, and since GETTEXT_POISON was
originally added the GIT_TEST_* env variables have become the common
idiom for turning on special test setups.
So change GETTEXT_POISON to work the same way. Now the
GETTEXT_POISON=YesPlease compile-time option is gone, and running the
tests with GIT_TEST_GETTEXT_POISON=[YesPlease|] can be toggled on/off
without recompiling.
This allows for conditionally amending tests to test with/without
poison, similar to what 859fdc0c3c ("commit-graph: define
GIT_TEST_COMMIT_GRAPH", 2018-08-29) did for GIT_TEST_COMMIT_GRAPH. Do
some of that, now we e.g. always run the t0205-gettext-poison.sh test.
I did enough there to remove the GETTEXT_POISON prerequisite, but its
inverse C_LOCALE_OUTPUT is still around, and surely some tests using
it can be converted to e.g. always set GIT_TEST_GETTEXT_POISON=.
Notes on the implementation:
* We still compile a dedicated GETTEXT_POISON build in Travis
CI. Perhaps this should be revisited and integrated into the
"linux-gcc" build, see ae59a4e44f ("travis: run tests with
GIT_TEST_SPLIT_INDEX", 2018-01-07) for prior art in that area. Then
again maybe not, see [2].
* We now skip a test in t0000-basic.sh under
GIT_TEST_GETTEXT_POISON=YesPlease that wasn't skipped before. This
test relies on C locale output, but due to an edge case in how the
previous implementation of GETTEXT_POISON worked (reading it from
GIT-BUILD-OPTIONS) wasn't enabling poison correctly. Now it does,
and needs to be skipped.
* The getenv() function is not reentrant, so out of paranoia about
code of the form:
printf(_("%s"), getenv("some-env"));
call use_gettext_poison() in our early setup in git_setup_gettext()
so we populate the "poison_requested" variable in a codepath that's
won't suffer from that race condition.
* We error out in the Makefile if you're still saying
GETTEXT_POISON=YesPlease to prompt users to change their
invocation.
* We should not print out poisoned messages during the test
initialization itself to keep it more readable, so the test library
hides the variable if set in $GIT_TEST_GETTEXT_POISON_ORIG during
setup. See [3].
See also [4] for more on the motivation behind this patch, and the
history of the GETTEXT_POISON facility.
1. https://public-inbox.org/git/871s8gd32p.fsf@evledraar.gmail.com/
2. https://public-inbox.org/git/20181102163725.GY30222@szeder.dev/
3. https://public-inbox.org/git/20181022202241.18629-2-szeder.dev@gmail.com/
4. https://public-inbox.org/git/878t2pd6yu.fsf@evledraar.gmail.com/
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Ever since we started using Travis CI, we specified the list of
packages to install in '.travis.yml' via the APT addon. While running
our builds on Travis CI's container-based infrastructure we didn't
have another choice, because that environment didn't support 'sudo',
and thus we didn't have permission to install packages ourselves. With
the switch to the VM-based infrastructure in the previous patch we do
get a working 'sudo', so we can install packages by running 'sudo
apt-get -y install ...' as well.
Let's make use of this and install necessary packages in
'ci/install-dependencies.sh', so all the dependencies (i.e. both
packages and "non-packages" (P4 and Git-LFS)) are handled in the same
file. Install gcc-8 only in the 'linux-gcc' build job; so far it has
been unnecessarily installed in the 'linux-clang' build job as well.
Print the versions of P4 and Git-LFS conditionally, i.e. only when
they have been installed; with this change even the static analysis
and documentation build jobs start using 'ci/install-dependencies.sh'
to install packages, and neither of these two build jobs depend on and
thus install those.
This change will presumably be beneficial for the upcoming Azure
Pipelines integration [1]: preliminary versions of that patch series
run a couple of 'apt-get' commands to install the necessary packages
before running 'ci/install-dependencies.sh', but with this patch it
will be sufficient to run only 'ci/install-dependencies.sh'.
[1] https://public-inbox.org/git/1a22efe849d6da79f2c639c62a1483361a130238.1539598316.git.gitgitgadget@gmail.com/
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The commit-graph and multi-pack-index features introduce optional
data structures that are not required for normal Git operations.
It is important to run the normal test suite without them enabled,
but it is helpful to also run the test suite using them.
Our continuous integration scripts include a second test stage that
runs with optional GIT_TEST_* variables enabled. Add the following
two variables to that stage:
GIT_TEST_COMMIT_GRAPH
GIT_TEST_MULTI_PACK_INDEX
This will slow down the operation, as we build a commit-graph file
after every 'git commit' operation and build a multi-pack-index
during every 'git repack' operation. However, it is important that
future changes are compatible with these features.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a recent update in 2.18 era, "git pack-objects" started
producing a larger than necessary packfiles by missing
opportunities to use large deltas.
* nd/pack-deltify-regression-fix:
pack-objects: fix performance issues on packing large deltas
The Travis CI scripts were taught to ship back the test data from
failed tests.
* sg/travis-retrieve-trash-upon-failure:
travis-ci: include the trash directories of failed tests in the trace log
The trash directory of a failed test might contain invaluable
information about the cause of the failure, but we have no access to
the trash directories of Travis CI build jobs. The only feedback we
get from there is the build job's trace log, so...
Modify 'ci/print-test-failures.sh' to create a tar.gz archive of the
trash directory of each failed test, encode that archive with base64,
and print the resulting block of ASCII text, so it gets embedded in
the trace log. Furthermore, run tests with '--immediate' to
faithfully preserve the failed state.
Extracting the trash directories from the trace log turned out to be a
bit of a hassle, partly because of the size of these logs (usually
resulting in several hundreds or even thousands of lines of
base64-encoded text), and partly because these logs have CRLF, CRCRLF
and occasionally even CRCRCRLF line endings, which cause 'base64 -d'
from coreutils to complain about "invalid input". For convenience add
a small script 'ci/util/extract-trash-dirs.sh', which will extract and
unpack all base64-encoded trash directories embedded in the log fed to
its standard input, and include an example command to be copy-pasted
into a terminal to do it all at the end of the failure report.
A few of our tests create sizeable trash directories, so limit the
size of each included base64-encoded block, let's say, to 1MB. And
just in case something fundamental gets broken and a lot of tests fail
at once, don't include trash directories when the combined size of the
included base64-encoded blocks would exceed 1MB.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Coccinelle's and in turn 'make coccicheck's exit code only indicates
that Coccinelle managed to finish its analysis without any errors
(e.g. no unknown --options, no missing files, no syntax errors in the
semantic patches, etc.), but it doesn't indicate whether it found any
undesired code patterns to transform or not. To find out the latter,
one has to look closer at 'make coccicheck's standard output and look
for lines like:
SPATCH result: contrib/coccinelle/<something>.cocci.patch
And this only indicates that there is something to transform, but to
see what the suggested transformations are one has to actually look
into those '*.cocci.patch' files.
This makes the automated static analysis build job on Travis CI not
particularly useful, because it neither draws our attention to
Coccinelle's findings, nor shows the actual findings. Consequently,
new topics introducing undesired code patterns graduated to master
on several occasions without anyone noticing.
The only way to draw attention in such an automated setting is to fail
the build job. Therefore, modify the 'ci/run-static-analysis.sh'
build script to check all the resulting '*.cocci.patch' files, and
fail the build job if any of them turns out to be not empty. Include
those files' contents, i.e. Coccinelle's suggested transformations, in
the build job's trace log, so we'll know why it failed.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently the static analysis build job runs Coccinelle using a single
'make' job. Using two parallel jobs cuts down the build job's run
time from around 10-12mins to 6-7mins, sometimes even under 6mins
(there is quite large variation between build job runtimes). More
than two parallel jobs don't seem to bring further runtime benefits.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Let's start with some background about oe_delta_size() and
oe_set_delta_size(). If you already know, skip the next paragraph.
These two are added in 0aca34e826 (pack-objects: shrink delta_size
field in struct object_entry - 2018-04-14) to help reduce 'struct
object_entry' size. The delta size field in this struct is reduced to
only contain max 1MB. So if any new delta is produced and larger than
1MB, it's dropped because we can't really save such a large size
anywhere. Fallback is provided in case existing packfiles already have
large deltas, then we can retrieve it from the pack.
While this should help small machines repacking large repos without
large deltas (i.e. less memory pressure), dropping large deltas during
the delta selection process could end up with worse pack files. And if
existing packfiles already have >1MB delta and pack-objects is
instructed to not reuse deltas, all of them will be dropped on the
floor, and the resulting pack would be definitely bigger.
There is also a regression in terms of CPU/IO if we have large on-disk
deltas because fallback code needs to parse the pack every time the
delta size is needed and just access to the mmap'd pack data is enough
for extra page faults when memory is under pressure.
Both of these issues were reported on the mailing list. Here's some
numbers for comparison.
Version Pack (MB) MaxRSS(kB) Time (s)
------- --------- ---------- --------
2.17.0 5498 43513628 2494.85
2.18.0 10531 40449596 4168.94
This patch provides a better fallback that is
- cheaper in terms of cpu and io because we won't have to read
existing pack files as much
- better in terms of pack size because the pack heuristics is back to
2.17.0 time, we do not drop large deltas at all
If we encounter any delta (on-disk or created during try_delta phase)
that is larger than the 1MB limit, we stop using delta_size_ field for
this because it can't contain such size anyway. A new array of delta
size is dynamically allocated and can hold all the deltas that 2.17.0
can. This array only contains delta sizes that delta_size_ can't
contain.
With this, we do not have to drop deltas in try_delta() anymore. Of
course the downside is we use slightly more memory, even compared to
2.17.0. But since this is considered an uncommon case, a bit more
memory consumption should not be a problem.
Delta size limit is also raised from 1MB to 16MB to better cover
common case and avoid that extra memory consumption (99.999% deltas in
this reported repo are under 12MB; Jeff noted binary artifacts topped
out at about 3MB in some other private repos). Other fields are
shuffled around to keep this struct packed tight. We don't use more
memory in common case even with this limit update.
A note about thread synchronization. Since this code can be run in
parallel during delta searching phase, we need a mutex. The realloc
part in packlist_alloc() is not protected because it only happens
during the object counting phase, which is always single-threaded.
Access to e->delta_size_ (and by extension
pack->delta_size[e - pack->objects]) is unprotected as before, the
thread scheduler in pack-objects must make sure "e" is never updated
by two different threads.
The area under the new lock is as small as possible, avoiding locking
at all in common case, since lock contention with high thread count
could be expensive (most blobs are small enough that delta compute
time is short and we end up taking the lock very often). The previous
attempt to always hold a lock in oe_delta_size() and
oe_set_delta_size() increases execution time by 33% when repacking
linux.git with with 40 threads.
Reported-by: Elijah Newren <newren@gmail.com>
Helped-by: Elijah Newren <newren@gmail.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
