From: Markus Elfring <Markus.Elfring@web.de>
To: David Wang <00107082@163.com>,
linux-fsdevel@vger.kernel.org,
Alexander Viro <viro@zeniv.linux.org.uk>,
Christian Brauner <brauner@kernel.org>
Cc: 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: Fri, 20 Dec 2024 15:34:12 +0100 [thread overview]
Message-ID: <4256c3d6-5769-444a-84d5-3b416015bc34@web.de> (raw)
In-Reply-To: <20241220140819.9887-1-00107082@163.com>
> 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
next prev parent reply other threads:[~2024-12-20 14:34 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-12-20 4:16 [PATCH] " 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 [this message]
2024-12-20 16:48 ` David Wang
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