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The perf tests write files recording the results of tests. These
results are later aggregated by 'aggregate.perl'. If the tests are run
multiple times, those results are overwritten by the new results. This
works just fine as long as there are only perf tests measuring the
times, whose results are stored in "$base".times files.
However 22bec79d1a ("t/perf: add infrastructure for measuring sizes",
2018-08-17) introduced a new type of test for measuring the size of
something. The results of this are written to "$base".size files.
"$base" is essentially made up of the basename of the script plus the
test number. So if test numbers shift because a new test was
introduced earlier in the script we might end up with both a ".times"
and a ".size" file for the same test. In the aggregation script the
".times" file is preferred over the ".size" file, so some size tests
might end with performance numbers from a previous run of the test.
This is mainly relevant when writing perf tests that check both
performance and sizes, and can get quite confusing during
developement.
We could fix this by doing a more thorough job of cleaning out old
".times" and ".size" files before running each test. However, an even
easier solution is to just use the same filename for both types of
measurement, meaning we'll always overwrite the previous result. We
don't even need to change the file format to distinguish the two;
aggregate.perl already decides which is which based on a regex of the
content (this may become ambiguous if we add new types in the future,
but we could easily add a header field to the file at that point).
Based on an initial patch from Thomas Gummerer, who discovered the
problem and did all of the analysis (which I stole for the commit
message above):
https://public-inbox.org/git/20191119185047.8550-1-t.gummerer@gmail.com/
Helped-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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As noted in preceding commits setting GIT_TEST_INSTALLED has never
been supported or documented, and as noted in an earlier t/perf/README
change to the extent that it's been documented nobody's notices that
the example hasn't worked since 3c8f12c96c ("test-lib: reorder and
include GIT-BUILD-OPTIONS a lot earlier", 2012-06-24).
We could directly support GIT_TEST_INSTALLED for invocations without
the "run" script, such as:
GIT_TEST_INSTALLED=../../ ./p0000-perf-lib-sanity.sh
GIT_TEST_INSTALLED=/home/avar/g/git ./p0000-perf-lib-sanity.sh
But while not having this "error" will "work", it won't write the the
resulting "test-results/*" files to the right place, and thus a
subsequent call to aggregate.perl won't work as expected.
Let's just tell the user that they need to use the "run" script,
which'll correctly deal with this and set the right
PERF_RESULTS_PREFIX.
If someone's in desperate need of bypassing "run" for whatever reason
they can trivially do so by setting "PERF_SET_GIT_TEST_INSTALLED", but
not we won't have people who expect GIT_TEST_INSTALLED to just work
wondering why their aggregation doesn't work, even though they're
running the right "git".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
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Follow-up my preceding change which fixed the immediate "./run
<revisions>" regression in 0baf78e7bc ("perf-lib.sh: rely on
test-lib.sh for --tee handling", 2019-03-15) and entirely get rid of
GIT_TEST_INSTALLED from perf-lib.sh (and aggregate.perl).
As noted in that change the dance we're doing with GIT_TEST_INSTALLED
perf-lib.sh isn't necessary, but there I was doing the most minimal
set of changes to quickly fix a regression.
But it's much simpler to never deal with the "GIT_TEST_INSTALLED" we
were setting in perf-lib.sh at all. Instead the run_dirs_helper() sets
the previously inferred $PERF_RESULTS_PREFIX directly.
Setting this at the callsite that's already best positioned to
exhaustively know about all the different cases we need to handle
where PERF_RESULTS_PREFIX isn't what we want already (the empty
string) makes the most sense. In one-off cases like:
./run ./p0000-perf-lib-sanity.sh
./p0000-perf-lib-sanity.sh
We'll just do the right thing because PERF_RESULTS_PREFIX will be
empty, and test-lib.sh takes care of finding where our git is.
Any refactoring of this code needs to change both the shell code and
the Perl code in aggregate.perl, because when running e.g.:
./run ../../ -- <test>
The "../../" path to a relative bindir needs to be munged to a
filename containing the results, and critically aggregate.perl does
not get passed the path to those aggregations, just "../..".
Let's fix cases where aggregate.perl would print e.g. ".." in its
report output for this, and "git" for "/home/avar/g/git", i.e. it
would always pick the last element. Now'll always print the full path
instead.
This also makes the code sturdier, e.g. you can feed "../.." to
"./run" and then an absolute path to the aggregate.perl script, as
long as the absolute path and "../.." resolved to the same directory
printing the aggregation will work.
Also simplify the "[_*]" on the RHS of "tr -c", we're trimming
everything to "_", so we don't need that.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
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Fix a really bad regression in 0baf78e7bc ("perf-lib.sh: rely on
test-lib.sh for --tee handling", 2019-03-15). Since that change all
runs of different <revisions> of git have used the git found in the
user's $PATH, e.g. /usr/bin/git instead of the <revision> we just
built and wanted to performance test.
The problem starts with GIT_TEST_INSTALLED not working like our
non-perf tests with the "run" script. I.e. you can't run performance
tests against a given installed git. Instead we expect to use it
ourselves to point GIT_TEST_INSTALLED to the <revision> we just built.
However, we had been relying on '$(cd "$GIT_TEST_INSTALLED" && pwd)'
to resolve that relative $GIT_TEST_INSTALLED to an absolute
path *before* test-lib.sh was loaded, in cases where it was
e.g. "build/<rev>/bin-wrappers" and we wanted "<abs_path>build/...".
This change post-dates another proposed solution by a few days[1], I
didn't notice that version when I initially wrote this. I'm doing the
most minimal thing to solve the regression here, a follow-up change
will move this result prefix selection logic entirely into the "run"
script.
This makes e.g. these cases all work:
./run . $PWD/../../ origin/master origin/next HEAD -- <tests>
As well as just a plain one-off:
./run <tests>
And, since we're passing down the new GIT_PERF_DIR_MYDIR_REL we make
sure the bug relating to aggregate.perl not finding our files as
described in 0baf78e7bc doesn't happen again.
What *doesn't* work is setting GIT_TEST_INSTALLED to a relative path,
this will subtly fail in test-lib.sh. This has always been the case
even before 0baf78e7bc, and as documented in t/README the
GIT_TEST_INSTALLED variable should be set to an absolute path (needs
to be set "to the bindir", which is always absolute), and the "perf"
framework expects to munge it itself.
Perhaps that should be dealt with in the future to allow manually
setting GIT_TEST_INSTALLED, but as a preceding commit showed the user
can just use the "run" script, which'll also pick the right output
directory for the test results as expected by aggregate.perl.
1. https://public-inbox.org/git/20190502222409.GA15631@sigill.intra.peff.net/
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
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Since its inception, the perf-lib.sh script has manually handled the
"--tee" option (and other options which imply it, like "--valgrind")
with a cut-and-pasted block from test-lib.sh. That block has grown stale
over the years, and has at least three problems:
1. It uses $SHELL to re-exec the script, whereas the version in
test-lib.sh learned to use $TEST_SHELL_PATH.
2. It does an ad-hoc search of the "$*" string, whereas test-lib.sh
learned to carefully parse the arguments left to right.
3. It never learned about --verbose-log (which also implies --tee),
so it would not trigger for that option.
This last one was especially annoying, because t/perf/run uses the
GIT_TEST_OPTS from your config.mak to run the perf scripts. So if you've
set, say, "-x --verbose-log" there, it will be passed as part of most
perf runs. And while this script doesn't recognize the option, the
test-lib.sh that we source _does_, and the behavior ends up being much
more annoying:
- as the comment at the top of the block says, we have to run this
tee code early, before we start munging variables (it says
GIT_BUILD_DIR, but the problematic variable is actually
GIT_TEST_INSTALLED).
- since we don't recognize --verbose-log, we don't trigger the block.
We go on to munge GIT_TEST_INSTALLED, converting it from a relative
to an absolute path.
- then we source test-lib.sh, which _does_ recognize --verbose-log. It
re-execs the script, which runs again. But this time with an
absolute version of GIT_TEST_INSTALLED.
- As a result, we copy the absolute version of GIT_TEST_INSTALLED into
perf_results_prefix. Instead of writing our results to the expected
"test-results/build_1234abcd.p1234-whatever.times", we instead write
them to "test-results/_full_path_to_repo_t_perf_build_1234...".
The aggregate.perl script doesn't expect this, and so it prints
"<missing>" for each result (even though it spent considerable time
running the tests!).
We can solve all of these in one blow by just deleting our custom
handling, and relying on the inclusion of test-lib.sh to handle --tee,
--verbose-log, etc.
There's one catch, though. We want to handle GIT_TEST_INSTALLED after
we've included test-lib.sh, since we want it un-munged in the re-exec'd
version of the script. But if we want to convert it from a relative
to an absolute path, we must do so before we load test-lib.sh, since it
will change our working directory. So we compute the absolute directory
first, store it away, then include test-lib.sh, and finally assign to
GIT_TEST_INSTALLED as appropriate.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Some of the functions in our test library check that they were invoked
properly with conditions like this:
test "$#" = 2 ||
error "bug in the test script: not 2 parameters to test-expect-success"
If this particular condition is triggered, then 'error' will abort the
whole test script with a bold red error message [1] right away.
However, under certain circumstances the test script will be aborted
completely silently, namely if:
- a similar condition in a test helper function like
'test_line_count' is triggered,
- which is invoked from the test script's "main" shell [2],
- and the test script is run manually (i.e. './t1234-foo.sh' as
opposed to 'make t1234-foo.sh' or 'make test') [3]
- and without the '--verbose' option,
because the error message is printed from within 'test_eval_', where
standard output is redirected either to /dev/null or to a log file.
The only indication that something is wrong is that not all tests in
the script are executed and at the end of the test script's output
there is no "# passed all N tests" message, which are subtle and can
easily go unnoticed, as I had to experience myself.
Send these "bug in the test script" error messages directly to the
test scripts standard error and thus to the terminal, so those bugs
will be much harder to overlook. Instead of updating all ~20 such
'error' calls with a redirection, let's add a BUG() function to
'test-lib.sh', wrapping an 'error' call with the proper redirection
and also including the common prefix of those error messages, and
convert all those call sites [4] to use this new BUG() function
instead.
[1] That particular error message from 'test_expect_success' is
printed in color only when running with or without '--verbose';
with '--tee' or '--verbose-log' the error is printed without
color, but it is printed to the terminal nonetheless.
[2] If such a condition is triggered in a subshell of a test, then
'error' won't be able to abort the whole test script, but only the
subshell, which in turn causes the test to fail in the usual way,
indicating loudly and clearly that something is wrong.
[3] Well, 'error' aborts the test script the same way when run
manually or by 'make' or 'prove', but both 'make' and 'prove' pay
attention to the test script's exit status, and even a silently
aborted test script would then trigger those tools' usual
noticable error messages.
[4] Strictly speaking, not all those 'error' calls need that
redirection to send their output to the terminal, see e.g.
'test_expect_success' in the opening example, but I think it's
better to be consistent.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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The main objective of scripts in the perf framework is to
run "test_perf", which measures the time it takes to run
some operation. However, it can also be interesting to see
the change in the output size of certain operations.
This patch introduces test_size, which records a single
numeric output from the test and shows it in the aggregated
output (with pretty printing and relative size comparison).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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About half of test_perf() is boilerplate preparing to run
_any_ test, and the other half is specifically running a
timing test. Let's split it into two functions, so that we
can reuse the boilerplate in future commits.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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When tests are run for a subsection defined in a config file, it is
better if the results for the current subsection are not overwritting
the results of a previous subsection.
So let's store the results for a subsection in a subdirectory of
"test-results/" with the subsection name.
The aggregate.perl, when it is run for a subsection, should then
aggregate the results found in "test-results/$GIT_PERF_SUBSECTION/".
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Add get_var_from_env_or_config() to easily set variables
from a config file if they are defined there and not already set.
This can also set them to a default value if one is provided.
As an example, use this function to set GIT_PERF_REPEAT_COUNT
from the perf.repeatCount config option or from the default
value.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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When the tested repo has an index.lock file it should be removed. This
file may be present if e.g. git-status previously crashed in that
repo, and it will make a lot of git commands fail. Let's try harder
and remove the lock.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Add a function to setup a fresh test repo via 'git init' to compliment
the existing functions to copy over a normal & large repo.
Some performance tests don't need any existing repository data at all
to be significant, e.g. tests which stress glob matches against single
pathological revisions or files, which I'm about to add in a
subsequent commit.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Since 1a0962dee (t/perf: fix regression in testing older
versions of git, 2016-06-22), we point "$MODERN_GIT" to a
copy of git that matches the t/perf script itself, and which
can be used for tasks outside of the actual timings. This is
needed because the setup done by perf scripts keeps moving
forward in time, and may use features that the older
versions of git we are testing do not have.
That commit used $MODERN_GIT to fix a case where we relied
on the relatively recent --git-path option. But if you go
back further still, there are more problems.
Since 7501b5921 (perf: make the tests work in worktrees,
2016-05-13), we use "git -C", but versions of git older than
44e1e4d67 (git: run in a directory given with -C option,
2013-09-09) don't know about "-C". So testing an old version
of git with a new version of t/perf will fail the setup
step.
We can fix this by using $MODERN_GIT during the setup;
there's no need to use the antique version, since it doesn't
affect the timings. Likewise, we'll adjust the "init"
invocation; antique versions of git called this "init-db".
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Allow t/perf framework to use the features from the most recent
version of Git even when testing an older installed version.
* jk/perf-any-version:
p4211: explicitly disable renames in no-rename test
t/perf: fix regression in testing older versions of git
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Commit 7501b59 (perf: make the tests work in worktrees,
2016-05-13) introduced the use of "git rev-parse --git-path"
in the perf-lib setup code. Because the to-be-tested version
of git is at the front of the $PATH when this code runs,
this means we cannot use modern versions of t/perf to test
versions of git older than v2.5.0 (when that option was
introduced).
This is a symptom of a more general problem. The t/perf
suite is essentially independent of git versions, and
ideally we would be able to run the most modern and complete
set of tests across many historical versions (to see how
they compare). But any setup code they run is therefore
required to use the lowest common denominator we expect to
test.
So let's introduce a new variable, $MODERN_GIT, that we can
use both in perf-lib and in the test setup to get a reliable
set of git features (we might change git and break some
tests, of course, but $MODERN_GIT is tied to the same
version of git as the t/perf scripts, so they can be fixed
or adjusted together).
This commit fixes the "--git-path" case, but does not
mass-convert existing setup code to use $MODERN_GIT. Most
setup code is fairly vanilla and will work with effectively
all versions. But now the tool is there to fix any other
issues we find going forward.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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As this developer has no access to MacOSX developer setups anymore,
Travis becomes the best bet to run performance tests on that OS.
However, on MacOSX /usr/bin/time is that good old BSD executable that
no Linux user cares about, as demonstrated by the perf-lib.sh's use
of GNU-ish extensions. And by the hard-coded path.
Let's just work around this issue by using gtime on MacOSX, the
Homebrew-provided GNU implementation onto which pretty much every
MacOSX power user falls back anyway.
To help other developers use Travis to run performance tests on
MacOSX, the .travis.yml file now sports a commented-out line that
installs GNU time via Homebrew.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Reviewed-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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In regular repositories $source_git and $objects_dir contain relative
paths based on $source. Go there to allow cp to resolve them.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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This patch makes perf-lib.sh more robust so that it can run correctly
even inside a worktree. For example, it assumed that $GIT_DIR/objects is
the objects directory (which is not the case for worktrees) and it used
the commondir file verbatim, even if it contained a relative path.
Furthermore, the setup code expected `git rev-parse --git-dir` to spit
out a relative path, which is also not true for worktrees. Let's just
change the code to accept both relative and absolute paths, by avoiding
the `cd` into the copied working directory.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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We already have a perfectly fine prereq to tell us whether it is safe to
use symlinks. So let's use it.
This fixes the performance tests in Git for Windows' SDK, where symlinks
are not really available ([*1*]). This is not an issue with Git for
Windows itself because it configures core.symlinks=false in its system
config. However, the system config is disabled for the performance
tests, for obvious reasons: we want them to be independent of the
vagaries of any local configuration.
Footnote *1*: Windows has symbolic links. Git for Windows disables them
by default, though (for example: in standard setups, non-admins lack the
privilege to create symbolic links). For details, see
https://github.com/git-for-windows/git/wiki/Symbolic-Links
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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When copying the test repository, we try to detect whether
the copy succeeded. However, most of the heavy lifting is
done inside a for loop, where our "break" will lose the exit
code of the failing "cp". We can take advantage of the fact
that we are in a subshell, and just "exit 1" to break out
with a code.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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A #! line in these files is misleading, since these scriptlets are
meant to be sourced with '.' (using whatever shell sources them)
instead of run directly using the interpreter named on the #! line.
Removing the #! line shouldn't hurt syntax highlighting since
these files have filenames ending with '.sh'. For documentation,
add a brief description of how the files are meant to be used in
place of the shebang line.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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* lf/echo-n-is-not-portable:
Avoid using `echo -n` anywhere
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`echo -n` is non-portable. The POSIX specification says:
Conforming applications that wish to do prompting without <newline>
characters or that could possibly be expecting to echo a -n, should
use the printf utility derived from the Ninth Edition system.
Since all of the affected shell scripts use a POSIX shell shebang,
replace `echo -n` invocations with printf.
Signed-off-by: Lukas Fleischer <git@cryptocrack.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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ae75342 test-lib: rearrange start/end of test_expect_* and test_skip
changed the way tests are started/stopped, but did not update the perf
tests. They were therefore giving the wrong output, because of the
wrong test count. Fix this by starting and stopping the tests
correctly.
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Acked-by: Thomas Rast <trast@inf.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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The malloc checks in tests are currently disabled. Actually evaluate
the variable for turning them off and enable them if it's unset.
Also use this opportunity to give it the more descriptive and
consistent name TEST_NO_MALLOC_CHECK.
Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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The most important in this change is to avoid affecting anything
when test-lib is used from perf-lib. It also limits the effect of
the MALLOC_CHECK only to what is run inside the actual test, and
uses a fixed MALLOC_PERTURB_ in order to avoid hurting repeatability
of the tests.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Jeff King wrote:
The seq command is GNU-ism, and is missing at least in older BSD
releases and their derivatives, not to mention antique
commercial Unixes.
We already purged it in b3431bc (Don't use seq in tests, not
everyone has it, 2007-05-02), but a few new instances have crept
in. They went unnoticed because they are in scripts that are not
run by default.
Replace them with test_seq that is implemented with a Perl snippet
(proposed by Jeff). This is better than inlining this snippet
everywhere it's needed because it's easier to read and it's easier
to change the implementation (e.g. to C) if we ever decide to remove
Perl from the test suite.
Note that test_seq is not a complete replacement for seq(1). It
just has what we need now, in addition that it makes it possible for
us to do something like "test_seq a m" if we wanted to in the
future.
There are also many places that do `for i in 1 2 3 ...` but I'm not sure
if it's worth converting them to test_seq. That would introduce running
more processes of Perl.
Signed-off-by: Michał Kiedrowicz <michal.kiedrowicz@gmail.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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The only bug right now is that $GIT_TEST_CMP is needed for test_cmp to
work.
However, we also export the three most important paths for tests:
TEST_DIRECTORY
TRASH_DIRECTORY
GIT_BUILD_DIR
Since they are available within test_expect_success, a future test
writer may expect them to also be defined in test_perf.
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Loading it in the subshells still referred to $TEST_DIRECTORY/..,
which was only correct in preliminary versions of perf-lib.sh
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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This introduces a performance testing framework under t/perf/. It
tries to be as close to the test-lib.sh infrastructure as possible,
and thus should be easy to get used to for git developers.
The following points were considered for the implementation:
1. You usually want to compare arbitrary revisions/build trees against
each other. They may not have the performance test under
consideration, or even the perf-lib.sh infrastructure.
To cope with this, the 'run' script lets you specify arbitrary
build dirs and revisions. It even automatically builds the revisions
if it doesn't have them at hand yet.
2. Usually you would not want to run all tests. It would take too
long anyway. The 'run' script lets you specify which tests to run;
or you can also do it manually. There is a Makefile for
discoverability and 'make clean', but it is not meant for
real-world use.
3. Creating test repos from scratch in every test is extremely
time-consuming, and shipping or downloading such large/weird repos
is out of the question.
We leave this decision to the user. Two different sizes of test
repos can be configured, and the scripts just copy one or more of
those (using hardlinks for the object store). By default it tries
to use the build tree's git.git repository.
This is fairly fast and versatile. Using a copy instead of a clone
preserves many properties that the user may want to test for, such
as lots of loose objects, unpacked refs, etc.
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Jeff King
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