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Joey Hess 2021-09-22 16:28:06 -04:00
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[[!comment format=mdwn
username="joey"
subject="""comment 3"""
date="2021-09-22T19:33:58Z"
content="""
Look at the 3 git add results, dividing windows runtime by linux:
1.9/0.05 = 38.00
4.5/0.08 = 56.25
13.1/0.36 = 36.39
The middle is slightly an outlier, and it would be better to have more data
points, but what this says to me is it's probably around 38x more expensive
on windows than on linux for git-annex smudge --clean to run.
git-annex smudge --clean makes on the order of 3000 syscalls, including
opening 200 files, execing git 30 times, and statting 400 files. That's
around 10x as many syscalls as git add makes. And it's run once per file. So
relatively small differences in syscall performance between windows and
linux can add up.
I've looked at just this kind of comparisons before, and it has always
seemed explainable by differences in syscall overhead. I don't
really see anything in your numbers that says otherwise.
I'm still curious if there's an older version of git-annex that was faster
(after it stopped using direct mode in v7).
If I've understood correctly, you don't seem to be saying that there is.
If it's always been this slow, then about all I can think to do to improve
it is profile git-annex smudge --clean on windows and see if anything other
than those syscalls is somehow being slow.
"""]]