Re: Git Scaling: What factors most affect Git performance for a large repo?

Ævar Arnfjörð Bjarmason [off-list ref] writes:

I actually ran this a few times while testing it, so this is a before
and after on a hot cache of linux.git with 406 tags v.s. ~140k. I ran
the gc + repack + bitmaps for both repos noted in an earlier reply of
mine, and took the fastest run out of 3:

    $ time (git log master -100 >/dev/null)
    Before: real    0m0.021s
    After: real    0m2.929s

Do you force --decorate with some config?  Or do you see similar
performance difference with "git rev-parse master", too?

    $ time (git status >/dev/null)
    # Around 150ms, no noticeable difference

This is understandable, as it will not look at any ref other than
HEAD.

On Fri, Feb 20, 2015 at 10:04 PM, Junio C Hamano [off-list ref] wrote:

Ævar Arnfjörð Bjarmason [off-list ref] writes:

quoted

I actually ran this a few times while testing it, so this is a before
and after on a hot cache of linux.git with 406 tags v.s. ~140k. I ran
the gc + repack + bitmaps for both repos noted in an earlier reply of
mine, and took the fastest run out of 3:

    $ time (git log master -100 >/dev/null)
    Before: real    0m0.021s
    After: real    0m2.929s

Do you force --decorate with some config?  Or do you see similar
performance difference with "git rev-parse master", too?

Yes, I had log.decorate=short set in my config. With --no-decorate:

    $ time (git log --no-decorate -100 >/dev/null)
    # Before: real    0m0.010s
    # After: real    0m0.065s

quoted

    $ time (git status >/dev/null)
    # Around 150ms, no noticeable difference

This is understandable, as it will not look at any ref other than
HEAD.