From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: Why is O_DSYNC on linux so slow / what's wrong with my SSD?
Date: Wed, 20 Nov 2013 04:54:46 -0800
Message-ID: <20131120125446.GA6284@infradead.org>
References: <528CA73B.9070604@profihost.ag>
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Cc: linux-fsdevel@vger.kernel.org, viro@zeniv.linux.org.uk,
	LKML <linux-kernel@vger.kernel.org>, matthew@wil.cx
To: Stefan Priebe - Profihost AG <s.priebe@profihost.ag>
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On Wed, Nov 20, 2013 at 01:12:43PM +0100, Stefan Priebe - Profihost AG wrote:
> Can anyone explain to me why O_DSYNC for my app on linux is so slow?

Because FreeBSD ignores O_DSYNC on block devices, it never sends a FLUSH
to the device.