Date: Thu, 11 Jan 2007 10:00:18 -0800 (PST)
From: Linus Torvalds <torvalds@osdl.org>
To: Alan <alan@lxorguk.ukuu.org.uk>
cc: Viktor <vvp01@inbox.ru>, Aubrey <aubreylee@gmail.com>,
       Hua Zhong <hzhong@gmail.com>, Hugh Dickins <hugh@veritas.com>,
       linux-kernel@vger.kernel.org, hch@infradead.org,
       kenneth.w.chen@intel.com, akpm@osdl.org, mjt@tls.msk.ru
Subject: Re: O_DIRECT question
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On Thu, 11 Jan 2007, Alan wrote:
> 
> Well you can - its called SG_IO and that really does get the OS out of
> the way. O_DIRECT gets crazy when you stop using it on devices directly
> and use it on files

Well, on a raw disk, O_DIRECT is fine too, but yeah, you might as well 
use SG_IO at that point. All of my issues are all about filesystems.

And filesystems is where people use O_DIRECT most. Almost nobody puts 
their database on a partition of its own these days, afaik. Perhaps for 
benchmarking or some really high-end stuff. Not "normal users".

		Linus
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