Date: Wed, 5 Dec 2007 00:24:54 +0000
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: "Jared Hulbert" <jaredeh@gmail.com>
Cc: "Chris Friesen" <cfriesen@nortel.com>, linux-kernel@vger.kernel.org
Subject: Re: solid state drive access and context switching
Message-ID: <20071205002454.52ea755c@the-village.bc.nu>
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On Tue, 4 Dec 2007 16:08:07 -0800
"Jared Hulbert" <jaredeh@gmail.com> wrote:

> On Dec 4, 2007 3:24 PM, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
> > > Right.  The trend is to hide the nastiness of NAND technology changes
> > > behind controllers.  In general I think this is a good thing.
> >
> > You miss the point - any controller you hide it behind almost inevitably
> > adds enough latency you don't want to use it synchronously.
> 
> I think I get it.  We keep saying that it's the latency is too high.
> I agree that most technologies out there have latencies that are too
> high.  Again I ask the question, what latencies do we have to hit
> before the sync options become worth it?

Probably about 1000 clocks but its always going to depend upon the
workload and whether any other work can be done usefully.

Alan
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