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Subject: Re: O_STREAMING has insufficient info - how about fadvise() ?
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Andrew Morton <akpm@digeo.com>
Cc: andersen@codepoet.org, Jamie Lokier <lk@tantalophile.demon.co.uk>,
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On Thu, 2002-10-10 at 16:34, Andrew Morton wrote:
> In 2.5, the radix tree gang lookup thing will do this search in O(zilch).
> 
> The other problem with fadvise is writebehind - there are up to
> 30 seconds' worth of dirty pages behind the application's write
> cursor which fadvise wouldn't be able to do anything with.  So
> the application would end up running fadvise(offset=0, length=current-pos)
> all the time.   Which is equivalent to O_STREAMING.

The write side is actually not very interesting. We can do that already
with fsync in a thread.

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