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From: Christian Brauner <brauner@kernel.org>
To: Max Kellermann <max.kellermann@ionos.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>,
	Jens Axboe <axboe@kernel.dk>,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] fs/splice: don't block splice_direct_to_actor() after data was read
Date: Tue, 26 Sep 2023 12:21:53 +0200	[thread overview]
Message-ID: <20230926-achtlos-ungeschehen-ee0e5f2c7666@brauner> (raw)
In-Reply-To: <20230926063609.2451260-1-max.kellermann@ionos.com>

> +		/*
> +		 * After at least one byte was read from the input
> +		 * file, don't wait for blocking I/O in the following
> +		 * loop iterations; instead of blocking for arbitrary
> +		 * amounts of time in the kernel, let userspace decide
> +		 * how to proceed.  This avoids excessive latency if
> +		 * the output is being consumed faster than the input
> +		 * file can fill it (e.g. sendfile() from a slow hard
> +		 * disk to a fast network).
> +		 */
> +		flags |= SPLICE_F_NOWAIT;
> +

Hm, so the thing that is worrysome about this change is that this may
cause regressions afaict as this is a pretty significant change from
current behavior.

  reply	other threads:[~2023-09-26 10:21 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-09-19  8:12 [PATCH] fs/splice: don't block splice_direct_to_actor() after data was read Max Kellermann
2023-09-19 14:18 ` Christian Brauner
2023-09-20 17:28   ` Jens Axboe
2023-09-20 18:16     ` Max Kellermann
2023-09-25 13:10       ` Christian Brauner
2023-09-26  6:36         ` [PATCH v2] " Max Kellermann
2023-09-26 10:21           ` Christian Brauner [this message]
2023-09-26 10:41             ` Max Kellermann
2023-09-26 12:26               ` Christian Brauner
2023-09-26  6:39         ` [PATCH] " Max Kellermann

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