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From:   Pin-yen Lin <treapking@chromium.org>
Date:   Sat, 10 Jun 2023 01:41:51 +0800
Message-ID: <CAEXTbpdDsoghsxbJqszx0OWWw1o9D8p9f_9-4OgOM-a-w7OzSA@mail.gmail.com>
Subject: Re: [PATCH] wifi: mwifiex: Replace RX workqueues with kthreads
To:     Kalle Valo <kvalo@kernel.org>
Cc:     Amitkumar Karwar <amitkarwar@gmail.com>,
        Ganapathi Bhat <ganapathi017@gmail.com>,
        Sharvari Harisangam <sharvari.harisangam@nxp.com>,
        Xinming Hu <huxinming820@gmail.com>,
        Brian Norris <briannorris@chromium.org>,
        linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org
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Hi Kalle,

On Fri, Jun 9, 2023 at 6:41=E2=80=AFPM Kalle Valo <kvalo@kernel.org> wrote:
>
> Pin-yen Lin <treapking@chromium.org> writes:
>
> > This improves the RX throughput likely by better locality for the work
> > loads.
> >
> > We tested this patch on Mediatek MT8173 Chromebooks, and it shows ~80%
> > Rx throughput improvement on high data rate test cases.
>
> 80%? That's huge from so small patch like this! What are the before and
> after numbers?

I realized that I might have over-simplified the background and the
impact of this patch...

The short answer to the question is that the throughput improved from
100 mbps to 180 mbps. The test was run on ChromeOS's v5.15 kernel
fork. More detailed test setting is mentioned in [1].

However, the throughput of the same test case on our v4.19 kernel is
320 mbps. That is, we observed a 320 mbps --> 100 mbps regression when
we tried to update the kernel version. This patch is more like a
mitigation of the regression. It improves the throughput, even though
it is still not as good as the older kernel.

That being said, this patch does improve the throughput, so we think
this patch can be landed into the mainline kernel.

Best regards,
Pin-yen

[1]: https://lore.kernel.org/all/ZFvpJb9Dh0FCkLQA@google.com/
>
> --
> https://patchwork.kernel.org/project/linux-wireless/list/
>
> https://wireless.wiki.kernel.org/en/developers/documentation/submittingpa=
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