From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Jan Beulich" Subject: Re: performance save/restore under xen-4.3.2 compared to kvm/qemu Date: Mon, 25 Aug 2014 14:02:04 +0100 Message-ID: <53FB4FEC020000780002D3BE@mail.emea.novell.com> References: <53FB2AAD.8040705@citrix.com> <53FB49B7020000780002D36A@mail.emea.novell.com> <53FB2E4E.7000200@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <53FB2E4E.7000200@citrix.com> Content-Disposition: inline List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Andrew Cooper Cc: ustermann.max@web.de, xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org >>> On 25.08.14 at 14:38, wrote: > On 25/08/14 13:35, Jan Beulich wrote: >>>>> On 25.08.14 at 14:23, wrote: >>> I have also identified a bottleneck in the Linux PVOps kernel where the >>> mmap batch ioctl takes a batch size of 1024 and generates 1024 batch >>> hypercalls of batch size 1. Fixing this will certainly make the >>> mapping/unmapping faster. >> Didn't Mats Petersson post a patch for this quite a while ago? Did >> this perhaps never get applied? > > That was a different issue if I remember correctly. I think it was to > do with the classic kernel using ioremap() for foreign domain memory. I certainly remember that patch having been against pv-ops... Jan