From: Oliver Neukum <oliver@neukum.org>
To: Linus Torvalds <torvalds@osdl.org>
Subject: Re: msync() behaviour broken for MS_ASYNC, revert patch?
Date: Fri, 10 Feb 2006 20:34:06 +0100
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Am Freitag, 10. Februar 2006 20:05 schrieb Linus Torvalds:
> So we may have different expectations, because we've seen different 
> patterns. Me, I've seen the "events are huge, and you stagger them", so 
> that the previous event has time to flow out to disk while you generate 
> the next one. There, MS_ASYNC starting IO is _wrong_, because the scale of 
> the event is just huge, so trying to push it through the IO subsystem asap 
> just makes everything suck.

Isn't the benefit of starting writing immediately greater the smaller
the area in question? If so, couldn't a heuristic be found to decide whether
to initiate IO at once?

	Oliver
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