On Tue, Jul 13 2021, Jeff Hostetler wrote:
> On 7/1/21 7:09 PM, Ævar Arnfjörð Bjarmason wrote:
>> On Thu, Jul 01 2021, Jeff Hostetler via GitGitGadget wrote:
>>
>>> From: Jeff Hostetler <jeffhost@xxxxxxxxxxxxx>
>>>
>>> Change p7519 to use a single "test-tool touch" command to update
>>> the mtime on a series of (thousands) files instead of invoking
>>> thousands of commands to update a single file.
>>>
>>> This is primarily for Windows where process creation is so
>>> very slow and reduces the test run time by minutes.
>>>
>>> Signed-off-by: Jeff Hostetler <jeffhost@xxxxxxxxxxxxx>
>>> ---
>>> t/perf/p7519-fsmonitor.sh | 14 ++++++--------
>>> 1 file changed, 6 insertions(+), 8 deletions(-)
>>>
>>> diff --git a/t/perf/p7519-fsmonitor.sh b/t/perf/p7519-fsmonitor.sh
>>> index 5eb5044a103..f74e6014a0a 100755
>>> --- a/t/perf/p7519-fsmonitor.sh
>>> +++ b/t/perf/p7519-fsmonitor.sh
>>> @@ -119,10 +119,11 @@ test_expect_success "one time repo setup" '
>>> fi &&
>>> mkdir 1_file 10_files 100_files 1000_files 10000_files &&
>>> - for i in $(test_seq 1 10); do touch 10_files/$i; done &&
>>> - for i in $(test_seq 1 100); do touch 100_files/$i; done &&
>>> - for i in $(test_seq 1 1000); do touch 1000_files/$i; done &&
>>> - for i in $(test_seq 1 10000); do touch 10000_files/$i; done &&
>>> + test-tool touch sequence --pattern="10_files/%d" --start=1 --count=10 &&
>>> + test-tool touch sequence --pattern="100_files/%d" --start=1 --count=100 &&
>>> + test-tool touch sequence --pattern="1000_files/%d" --start=1 --count=1000 &&
>>> + test-tool touch sequence --pattern="10000_files/%d" --start=1 --count=10000 &&
>>> +
>>> git add 1_file 10_files 100_files 1000_files 10000_files &&
>>> git commit -qm "Add files" &&
>>> @@ -200,15 +201,12 @@ test_fsmonitor_suite() {
>>> # Update the mtimes on upto 100k files to make status think
>>> # that they are dirty. For simplicity, omit any files with
>>> # LFs (i.e. anything that ls-files thinks it needs to dquote).
>>> - # Then fully backslash-quote the paths to capture any
>>> - # whitespace so that they pass thru xargs properly.
>>> #
>>> test_perf_w_drop_caches "status (dirty) ($DESC)" '
>>> git ls-files | \
>>> head -100000 | \
>>> grep -v \" | \
>>> - sed '\''s/\(.\)/\\\1/g'\'' | \
>>> - xargs test-tool chmtime -300 &&
>>> + test-tool touch stdin &&
>>> git status
>>> '
>> Did you try to replace this with some variant of:
>> test_seq 1 10000 | xargs touch
>> Which (depending on your xargs version) would invoke "touch"
>> commands
>> with however many argv items it thinks you can handle.
>>
>
> a quick test on my Windows machine shows that
>
> test_seq 1 10000 | xargs touch
>
> takes 3.1 seconds.
>
> just a simple
>
> test_seq 1 10000 >/dev/null
>
> take 0.2 seconds.
>
> using my test-tool helper cuts that time in half.
There's what Elijah mentioned about test_seq, so maybe it's just that.
But what I was suggesting was using the xargs mode where it does N
arguments at a time.
Does this work for you, and does it cause xargs to invoke "touch" with
the relevant N number of arguments, and does it help with the
performance?
test_seq 1 10000 | xargs touch
test_seq 1 10000 | xargs -n 10 touch
test_seq 1 10000 | xargs -n 100 touch
test_seq 1 10000 | xargs -n 1000 touch
etc.
Also I didn't notice this before, but the -300 part of "chmtime -300"
was redundant before then? I.e. you're implicitly changing it to "=+0"
instead with your "touch" helper, are you not?
