On Thu, Mar 29, 2012 at 9:15 PM, Federico Fanton <federico@xxxxxxxxxxxx> wrote: > Hi everyone! > We have an Hylafax 5.2.5 CentOS 5 installation hosted inside a Xen virtual > machine. It works quite well, but now I'm in the process of > upgrading/migrating it to a KVM virtual machine running Ubuntu 10.04. > > The problem I'm having is that - while receiving works fine - sending faxes > is extremely unreliable, I get lots of "No response to MPS repeated 3 > tries", or "Failure to transmit clean ECM image data", just what would > happen if the phone line was noisy. > > Since the line, modem and configuration files I'm using are the same as > before, I thought that it could be a KVM scheduling issue, but even setting > cpu_shares to 10240 instead of 1024 doesn't change a thing... > > I've tried asking on the Hylafax ML, and they say that > > "generally speaking I'm very skeptical of real-time performance for > virtualized machines and especially virtualized serial hardware. Because fax > is time-sensitive it's certainly possible for the virtual machine to not be > attentive-enough to it." > > Are there any success stories on running Hylafax on KVM? What could I try to > make it more "attentive"? > > > Here's how I'm mapping the serial port (where the modem is connected): > > <serial type='dev'> > <source path='/dev/ttyS0'/> > <target port='0'/> > </serial> > > > And how I tuned the VM: > > <cputune> > <shares>10240</shares> > <period>100000</period> > <quota>-1</quota> > </cputune> > > > Many thanks for your time! > > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html I've run hylafax under KVM in guest without any problems. ( not sure about configuration - since have no longer access to that site ) I think I've been using USB-2-serial adapter. and run kvm without libvirt -- -- Michael -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
