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Date: Mon, 20 Aug 2012 12:57:57 +0200
From: Jens Axboe <axboe@kernel.dk>
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Subject: Re: Direct io on Ubuntu i386?
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To: Greg Sullivan <greg.sullivan@sullivang.net>
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On 08/20/2012 02:57 AM, Greg Sullivan wrote:
> I'm trying to do direct io (to avoid the file system cache) on Ubuntu
> i386. I've tried direct=1, and tried the io engines sync and libaio -
> it always seems to use the cache.
> 
> Is there a way to bypass the file system cache on Ubuntu? I've got a
> vanilla install using the automated Ubuntu installer for Windows i386
> 32-bit (dual boot).

direct=1 will certainly bypass the cache on Linux, regardless of
version. What makes you suspect otherwise?

-- 
Jens Axboe