On Sat, Jan 15, 2022 at 12:06 AM Andrew Morton
<akpm@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> Speed up fork() by up to 40% by refcounting the anon vma name field.
What?
No.
This doesn't speed up anything at all.
The refcounting of the anon-vma name field avoids a 40% regression
that comes from adding the field in the first place, but this commit
message makes it sound like this series is speeding up fork() by 40%.
I don't mind the series, but I absolutely mind these kinds of horribly
misleading commit messages.
This is literally the first commit in the series - and the series in
no way improves performance by 40% in the end, it just first makes it
worse, and then fixes the regression.
I can speed up any function by a thousand percent - if I'm just
allowed to make it horribly slow first, and only count the final
speedup win when I remove the overhead of the garbage I added.
Linus
