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Message-ID: <5ae01623-3f0f-4c19-bf5e-29e39e9e9349@leemhuis.info>
Date: Mon, 22 Jan 2024 11:50:42 +0100
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Subject: Re: [MAYBE REGRESSION] kbuild time of kernel compiling
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To: Jingbo Xu <jefflexu@linux.alibaba.com>, linux-kbuild@vger.kernel.org,
 masahiroy@kernel.org, nathan@kernel.org, ndesaulniers@google.com,
 nicolas@fjasle.eu,
 Linux kernel regressions list <regressions@lists.linux.dev>
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From: "Linux regression tracking (Thorsten Leemhuis)"
 <regressions@leemhuis.info>
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On 22.01.24 09:32, Jingbo Xu wrote:
> 
> I noticed a regression of kbuild time in v6.7, especially when running
> `make` command when all images have already been compiled.  In v6.6 it
> takes ~3s, while in v6.7 it takes ~18s.
> 
> I'm not sure if it's a known issue, or an extra action configurable with
> a "CONFIG_XX" option.
> [...]

Not my area of expertise, so take this with a gain of salt, as I might
mislead you. Nevertheless:

One problem with compile times in 6.7 was noticed and fixed in mainline;
I wonder if that is the same issue as yours:

https://lore.kernel.org/lkml/18c6df0d-45ed-450c-9eda-95160a2bbb8e@gmail.com/
https://git.kernel.org/torvalds/c/31e97d7c9ae3de072d7b424b2cf706a03ec10720

I think there was another issue, but can't remember it from the top of
my head. Maybe simply checking if 6.8-rc1 fixes things might be the best.

Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
--
Everything you wanna know about Linux kernel regression tracking:
https://linux-regtracking.leemhuis.info/about/#tldr
If I did something stupid, please tell me, as explained on that page.