linux-kernel - Re: [PATCH 0/2] x86: Remove ideal

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Message-ID: <20210315171516.GG20497@zn.tnic>
Date:   Mon, 15 Mar 2021 18:15:16 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     Sedat Dilek <sedat.dilek@...il.com>
Cc:     Peter Zijlstra <peterz@...radead.org>, x86@...nel.org,
        rostedt@...dmis.org, hpa@...or.com, torvalds@...uxfoundation.org,
        linux-kernel@...r.kernel.org, linux-toolchains@...r.kernel.org,
        jpoimboe@...hat.com, alexei.starovoitov@...il.com,
        mhiramat@...nel.org
Subject: Re: [PATCH 0/2] x86: Remove ideal_nops[]

On Mon, Mar 15, 2021 at 06:04:41PM +0100, Sedat Dilek wrote:
> Here some fresh numbers:

Lemme paste my previous reply which still holds true here:

"There's a reason I have -s for silent in the build - printing output
during the build creates a *lot* of variance. And you have excessive
printing with V=1 and KBUILD_VERBOSE=1.

Also, you need to repeat those workloads a couple of times - one is not
enough. That's why I have --repeat 5 in there.

Also, you need --pre=/root/bin/pre-build-kernel.sh where that script is:

---
#!/bin/bash
echo $0

make -s clean
echo 3 > /proc/sys/vm/drop_caches
---

so that you can avoid pagecache influence."

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette