From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: Re: [PATCH] qemu vnc updates Date: Tue, 26 Feb 2008 11:29:44 -0600 Message-ID: <47C44C88.2010205@codemonkey.ws> References: <47C3F6FA.6080506@eu.citrix.com> <47C43B37.1010209@codemonkey.ws> <20080226162224.GI30568@redhat.com> <47C43FA0.60808@eu.citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <47C43FA0.60808@eu.citrix.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: Stefano Stabellini Cc: xen-devel@lists.xensource.com, "Daniel P. Berrange" List-Id: xen-devel@lists.xenproject.org Stefano Stabellini wrote: > > I have just re-read the rfb protocol spec and it specifies quite > clearly that framebuffer updates are sent in response to framebuffer > update requests. > However it is true that the server can collapse multiple requests in a > single reply. It is also clear that the reply can come at any time. > > I have seen the linux vncviewer client breaking because of race > conditions due to this problem. You mean realvnc? The race condition is due to it's use of SetPixelFormat. By slowing the updates, what you're really doing is just working around that race condition. That's not a proper solution though. This goes away if you set the realvnc options so that it doesn't change the pixel format from what the server specifies. Regards, Anthony Liguori