public inbox for linux-fsdevel@vger.kernel.org
 help / color / mirror / Atom feed
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

      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]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1748fa92.b227.193e4f8d6a3.Coremail.00107082@163.com \
    --to=00107082@163.com \
    --cc=Markus.Elfring@web.de \
    --cc=brauner@kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=surenb@google.com \
    --cc=viro@zeniv.linux.org.uk \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox