From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir@xen.org>
Subject: Re: credit2 data structures
Date: Thu, 13 Oct 2011 11:57:59 +0100
Message-ID: <CABC82C7.329CD%keir@xen.org>
References: <CAFLBxZaHwav97=PVvZDTKzBVaeGc9FYh4xs9mj3cC=WbEzTZtw@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain;
	charset="US-ASCII"
Content-Transfer-Encoding: 7bit
Return-path: <xen-devel-bounces@lists.xensource.com>
In-Reply-To: <CAFLBxZaHwav97=PVvZDTKzBVaeGc9FYh4xs9mj3cC=WbEzTZtw@mail.gmail.com>
List-Unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xensource.com>
List-Help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-Subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
Sender: xen-devel-bounces@lists.xensource.com
Errors-To: xen-devel-bounces@lists.xensource.com
To: George Dunlap <George.Dunlap@eu.citrix.com>, Jan Beulich <JBeulich@suse.com>
Cc: "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>
List-Id: xen-devel@lists.xenproject.org

On 13/10/2011 11:11, "George Dunlap" <George.Dunlap@eu.citrix.com> wrote:

> For one thing, the number of runqueues in credit2 is actually meant to
> be smaller than the number of logical cpus -- it's meant to be one per
> L2 cache, which should have between 2 and 8 logical cpus, depending on
> the architecture.  I just put NR_CPUS because it was easier to get
> working.  Making that an array of pointers, which is allocated on an
> as-needed basis, should reduce that requirement a great deal.

That would suffice. If we can put per-cpu stuff in the per_cpu() data area
then even better. The fact that credit2 burns a couple of kB per CPU isn't a
problem at all, as long as it does it only for active CPUs.

 -- Keir