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From:   Huacai Chen <chenhc@lemote.com>
Date:   Tue, 15 Oct 2019 11:36:59 +0800
Message-ID: <CAAhV-H573fv+NVqBRgU38BRDDX=syj3gUqnJqRp4CdBx+QcdpQ@mail.gmail.com>
Subject: Re: [PATCH] MIPS: Loongson: Make default kernel log buffer size as
 128KB for Loongson3
To:     Tiezhu Yang <yangtiezhu@loongson.cn>
Cc:     Paul Burton <paul.burton@mips.com>,
        Ralf Baechle <ralf@linux-mips.org>,
        James Hogan <jhogan@kernel.org>,
        "open list:MIPS" <linux-mips@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Tue, Oct 15, 2019 at 10:12 AM Tiezhu Yang <yangtiezhu@loongson.cn> wrote:
>
> When I update kernel with loongson3_defconfig based on the Loongson 3A3000
> platform, then using dmesg command to show kernel ring buffer, the initial
> kernel messages have disappeared due to the log buffer is too small, it is
> better to change the default kernel log buffer size from 16KB to 128KB.
>
> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
> ---
>  arch/mips/configs/loongson3_defconfig | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/mips/configs/loongson3_defconfig b/arch/mips/configs/loongson3_defconfig
> index 90ee008..3aa2201 100644
> --- a/arch/mips/configs/loongson3_defconfig
> +++ b/arch/mips/configs/loongson3_defconfig
> @@ -12,7 +12,7 @@ CONFIG_TASKSTATS=y
>  CONFIG_TASK_DELAY_ACCT=y
>  CONFIG_TASK_XACCT=y
>  CONFIG_TASK_IO_ACCOUNTING=y
> -CONFIG_LOG_BUF_SHIFT=14
> +CONFIG_LOG_BUF_SHIFT=17
Hi, Tiezhu,

Why you choose 128KB but not 64KB or 256KB? I found 64KB is enough for
our cases. And if you really need more, I think 256KB could be better
because there are many platforms choose 256KB.

Huacai

>  CONFIG_MEMCG=y
>  CONFIG_MEMCG_SWAP=y
>  CONFIG_BLK_CGROUP=y
> --
> 2.1.0
>
>