Re: [PATCH] mm/uffd: UFFD_FEATURE_WP_ZEROPAGE

From: Peter Xu
Date: Fri Feb 17 2023 - 18:11:17 EST


Hi, Muhammad,

On Fri, Feb 17, 2023 at 05:31:19PM +0500, Muhammad Usama Anjum wrote:
> I've just ran my single threaded selftest [1] over an over again to get
> some numbers.
>
> Without zeropage
> qemu has 6 cores: 26.0355

Did you count in the time of read prefault? Or did you not prefault at
all?

> With zeropage
> qemu has 6 cores: 39.203
>
> 33% worse performance with zero pages
>
> Definitely, there can be better benchmark application. Please let me know
> if I should write better benchmarks on my end.
>
> [1]
> https://lore.kernel.org/all/20230202112915.867409-7-usama.anjum@xxxxxxxxxxxxx

I'll have a closer look too next week.

Thanks,

--
Peter Xu