From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: Re: improving VNC performance Date: Tue, 26 Jul 2011 10:33:29 +0200 Message-ID: <4E2E7BD9.6050309@redhat.com> References: <4E2E62A0.1050103@redhat.com> <20110726082716.GA29346@ocelot.phlegethon.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20110726082716.GA29346@ocelot.phlegethon.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Tim Deegan Cc: James Harper , xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org On 07/26/2011 10:27 AM, Tim Deegan wrote: > At 08:45 +0200 on 26 Jul (1311669952), Paolo Bonzini wrote: >> On 07/26/2011 04:00 AM, James Harper wrote: >>> It would be really nice to be able to cut&paste (would require a >>> userspace app), and to fake some accelerator functions (eg block moves). >> >> Block moves are accelerated if you use the Cirrus VGA. Nothing else is, >> though. :) > > Actually we found that it's faster to turn that acceleration off, since > it's not really accelerated --- it'll be a memcpy either in domU or in > qemu, and you might as well skip the (slow, synchronous) emulated > register writes that domU would use to drive the blitter. Yes, it's slower but saves bandwidth. It depends on your use case. Paolo