<p dir="ltr">Yes, during my experimentation I made mistakes, when it started to work, I kept it :)</p>
<div class="gmail_quote">On 26 Feb 2016 10:54 am, "Rokas Kupstys" <<a href="mailto:rokups@zoho.com">rokups@zoho.com</a>> wrote:<br type="attribution"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
  
    
  
  <div bgcolor="#FFFFFF" text="#000000">
    Hmm what you just wrote i dont understand.<br>
    <blockquote type="cite">CONFIG_RCU_NOCB_CPU_ALL=y</blockquote>
    Documentation:<br>
    <blockquote type="cite">This option forces all CPUs to be no-CBs
      CPUs. The rcu_nocbs=
      boot parameter will be ignored.</blockquote>
    So at least rcu_nocbs kernel parameter should not be needed as i
    understand. Right?<br>
    <br>
    Still ill try these settings, cant be any worse :)<br>
    <br>
    <div>On 2016.02.26 11:16, Quentin Deldycke
      wrote:<br>
    </div>
    <blockquote type="cite">
      <div dir="ltr">
        <div>
          <div>
            <div>
              <div>
                <div>
                  <div>Mainly:<br>
                    <br>
                    CONFIG_NO_HZ_FULL=y<br>
                    CONFIG_RCU_NOCB_CPU_ALL=y<br>
                    <br>
                  </div>
                  Using cgroups / cpu pinnning, the cores won't have to
                  handle any kernel tick, but only run qemu<br>
                  <br>
                </div>
                For my i7 4790k, i am force to put vm on 3 threads (the
                main of my 3 cores). So kernel parameter:<br>
                <br>
                nohz_full=1,2,3,5,6,7 rcu_nocbs=1,2,3,5,6,7<br>
                <br>
              </div>
              and my vm run on threads 1,2,3 (main thread of cores
              1,2,3)<br>
            </div>
            and qemu emulator run on threads 5,6,7 (sub threads of cores
            1,2,3)<br>
            <br>
          </div>
          <div>Amd cards seems more affected by DPC than nvidia ones.<br>
          </div>
          <div><br>
          </div>
          Note an interesting thing:<br>
          <br>
          <a href="http://www.guru3d.com/articles-pages/rise-of-the-tomb-raider-pc-graphics-performance-benchmark-review,9.html" target="_blank">http://www.guru3d.com/articles-pages/rise-of-the-tomb-raider-pc-graphics-performance-benchmark-review,9.html</a><br>
          <br>
        </div>
        amd and multi cores is... erratic :)</div>
      <div class="gmail_extra"><br clear="all">
        <div>
          <div>
            <div dir="ltr">--
              <div>Deldycke Quentin<br>
              </div>
              <div>
                <div><br>
                </div>
              </div>
            </div>
          </div>
        </div>
        <br>
        <div class="gmail_quote">On 26 February 2016 at 09:53, Rokas
          Kupstys <span dir="ltr"><<a href="mailto:rokups@zoho.com" target="_blank">rokups@zoho.com</a>></span>
          wrote:<br>
          <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
            <div bgcolor="#FFFFFF" text="#000000"> Could you elaborate
              on config differences? Still hunting for something that
              could help bringing DPC latency down since VM gaming is no
              go due to that..
              <div>
                <div><br>
                  <br>
                  <div>On 2016.02.26 10:51, Quentin Deldycke wrote:<br>
                  </div>
                  <blockquote type="cite">
                    <div dir="ltr">
                      <div>
                        <div>
                          <div>
                            <div>For my part:<br>
                              <br>
                            </div>
                            debian with some experimental package. When
                            new kernel is out, i recompile it with some
                            difference in config.<br>
                            <br>
                          </div>
                          But right now, 4.5 rc4.<br>
                          <br>
                        </div>
                        No problem with the host since ages. Plasma is
                        buggy but... i think on every distro xD<br>
                        <br>
                      </div>
                    </div>
                    <div class="gmail_extra"><br clear="all">
                      <div>
                        <div>
                          <div dir="ltr">--
                            <div>Deldycke Quentin<br>
                            </div>
                            <div>
                              <div><br>
                              </div>
                            </div>
                          </div>
                        </div>
                      </div>
                      <br>
                      <div class="gmail_quote">On 26 February 2016 at
                        09:43, Stein van Broekhoven <span dir="ltr"><<a href="mailto:stein@aapjeisbaas.nl" target="_blank"><a href="mailto:stein@aapjeisbaas.nl" target="_blank">stein@aapjeisbaas.nl</a></a>></span>
                        wrote:<br>
                        <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Dear All,<br>
                          <br>
                          What do you consider the distro of choice for
                          a stable vm gaming build?<br>
                          At the moment I'm on solus because it has
                          4.4.0 kernel by default and I like the
                          project.<br>
                          Got libvirtd & virsh working with qemu but
                          just can't get passthrough to work as of now.<br>
                          <br>
                          I have a :<br>
                          ASUS SABERTOOTH 990FX v1 with FX-8120<br>
                          Ati Radeon 6xxx<br>
                          Ati Radeon 5xxx<br>
                          <br>
                          I had it working at some point with ubuntu but
                          that is some time ago and don't remember how.<br>
                          <br>
                          <br>
                          Kind regards,<br>
                          <br>
                          Stein van Broekhoven / System administrator<br>
                          <a href="mailto:stein@aapjeisbaas.nl" target="_blank">stein@aapjeisbaas.nl</a><br>
                          <br>
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