From: "David Wang" <00107082@163.com>
To: "Markus Elfring" <Markus.Elfring@web.de>
Cc: linux-fsdevel@vger.kernel.org,
"Alexander Viro" <viro@zeniv.linux.org.uk>,
"Christian Brauner" <brauner@kernel.org>,
LKML <linux-kernel@vger.kernel.org>,
"Suren Baghdasaryan" <surenb@google.com>
Subject: Re: [PATCH v2] seq_file: copy as much as possible to user buffer in seq_read()
Date: Sat, 21 Dec 2024 00:48:53 +0800 (CST) [thread overview]
Message-ID: <1748fa92.b227.193e4f8d6a3.Coremail.00107082@163.com> (raw)
In-Reply-To: <4256c3d6-5769-444a-84d5-3b416015bc34@web.de>
At 2024-12-20 22:34:12, "Markus Elfring" <Markus.Elfring@web.de> wrote:
>> seq_read() yields at most seq_file->size bytes to userspace, …
>
> user space?
>
>
>…
>> $ strace -T -e read cat /proc/interrupts > /dev/null
>…
>> 45 read(3, "", 131072) = 0 <0.000010>
>> On a system with hundreds of cpus, it would need …
>
> CPUs?
>
>
>Is it a bit nicer to separate test output and subsequent comments by blank lines?
>
>
>…
>> Fill up user buffer as much as possible in seq_read(), extra read
>> calls can be avoided with a larger user buffer, and 2%~10% performance
>> improvement would be observed:
>Will it help to split such a paragraph into three sentences
>(on separate lines)?
>
>Regards,
>Markus
Thanks for the comments, I will address it later.
Any concern about the code?
David
prev parent reply other threads:[~2024-12-20 16:49 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-12-20 4:16 [PATCH] seq_file: copy as much as possible to user buffer in seq_read() David Wang
2024-12-20 12:13 ` Markus Elfring
2024-12-20 13:54 ` David Wang
2024-12-20 14:08 ` [PATCH v2] " David Wang
2024-12-20 14:34 ` Markus Elfring
2024-12-20 16:48 ` David Wang [this message]
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