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Message-ID: <1323340668.3904.21.camel@lappy>
Subject: Re: [PATCH] virtio-ring: Use threshold for switching to indirect
 descriptors
From: Sasha Levin <levinsasha928@gmail.com>
To: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>, Avi Kivity <avi@redhat.com>,
        linux-kernel@vger.kernel.org,
        virtualization@lists.linux-foundation.org, kvm@vger.kernel.org,
        markmc@redhat.com
Date: Thu, 08 Dec 2011 12:37:48 +0200
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On Thu, 2011-12-08 at 20:14 +1030, Rusty Russell wrote:
> On Wed, 7 Dec 2011 17:48:17 +0200, "Michael S. Tsirkin" <mst@redhat.com> wrote:
> > On Wed, Dec 07, 2011 at 04:02:45PM +0200, Sasha Levin wrote:
> > > On Sun, 2011-12-04 at 20:23 +0200, Sasha Levin wrote:
> > > 
> > > [snip]
> > > 
> > > Rusty, Michael, does the below looks a reasonable optimization for you?
> > 
> > OK overall but a bit hard to say for sure as it looks pretty incomplete ...
> 
> A static threshold is very hackish; we need to either initialize it to
> a proven-good value (since noone will ever change it) or be cleverer.

I'll better wait to see how the threshold issue is resolved, and
possibly do it as a dynamic value which depends on the threshold.

I doubt theres one magic value which would work for all.

-- 

Sasha.