From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keir Fraser Subject: Re: long latency of domain shutdown Date: Thu, 08 May 2008 11:12:12 +0100 Message-ID: References: <4822EAE1.76E4.0078.0@novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4822EAE1.76E4.0078.0@novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Jan Beulich Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org On 8/5/08 10:58, "Jan Beulich" wrote: > While looking at this I wondered whether there really is a way for > Xen heap pages to end up being guest page tables (or similarly > descriptor table ones)? I would think if that happened this would be > a bug (and perhaps a security issue). If it cannot happen, then the > RELMEM_* states could be simplified and > domain_relinquish_resources() shortened. You mean just force page-table type counts to zero, and drop main reference count by the same amount? Might work. Would need some thought. 8500 cycles per pte is pretty fantastic. I suppose a few atomic ops are involved. Are you running on an old P4? :-) -- Keir