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Date:   Sat, 22 Feb 2020 09:24:14 -0500
From:   "Alex Xu (Hello71)" <alex_y_xu@yahoo.ca>
Subject: Re: [PATCH] kbuild: move -pipe to global KBUILD_CFLAGS
To:     Nathan Chancellor <natechancellor@gmail.com>
Cc:     Russell King <linux@armlinux.org.uk>, linux-kbuild@vger.kernel.org,
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Excerpts from Nathan Chancellor's message of February 22, 2020 3:01 am:
> I used hyperfine [1] to run a quick benchmark with a freshly built
> GCC 9.2.0 for x86 and aarch64 and here are the results:
>=20
> In both cases it seems like performance regresses (by 1% but still) but
> maybe it is my machine, even though this benchmark was done on a
> different machine than the one from my commit back in 2018.
>=20
> I am not sure I would write off these results, since I did the benchmark
> 25 times on each one back to back, eliminating most of the variance that
> you described.
>=20
> [1]: https://github.com/sharkdp/hyperfine
>=20
> Cheers,
> Nathan
>=20

What kernel version are you running? Do you have the 5.6 pipe reworks?