<div dir="ltr"><div dir="ltr"><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">Den sön 7 juni 2020 kl 13:22 skrev rosea.grammostola <<a href="mailto:rosea.grammostola@gmail.com">rosea.grammostola@gmail.com</a>>:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
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<div>On 6/4/20 3:09 PM, Paul Davis wrote:<br>
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<div style="font-family:arial,helvetica,sans-serif">This is wrong. The behavior of a
"normal", "low latency" and "preempt-RT" kernel are all
different, and for realtime audio work, the correct
behavior is only going to happen with a "preempt-RT"
kernel.</div>
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<div style="font-family:arial,helvetica,sans-serif">However ...</div>
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<div style="font-family:arial,helvetica,sans-serif">The behavior of the normal and "low
latency" kernels have changed over the years too, and on
*some* systems (from a hardware perspective), they will
function similarly enough to a "preempt-RT" kernel that a
realtime audio workflow will be just fine. In addition,
the "behavior" gap between a "preempt-RT" kernel and a
normal kernel will be less and less apparent as the
latency settings (buffer/period size) become more relaxed
(i.e. grow larger). <br>
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<div style="font-family:arial,helvetica,sans-serif">How do you know which systems this
is true for? You just have to try it. It is a complicated
mixture of many different aspects of the hardware. There's
an overview of the kinds of things that can contribute to
the need for a "preempt-RT" kernel here:</div>
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<div style="font-family:arial,helvetica,sans-serif"><a href="https://manual.ardour.org/setting-up-your-system/the-right-computer-system-for-digital-audio/" target="_blank">https://manual.ardour.org/setting-up-your-system/the-right-computer-system-for-digital-audio/</a></div>
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<p>Useful information.</p>
<p>Fwiw, I did my best to optimize a thinkpad t420 laptop for
linuxaudio using the realtime script from the wiki mostly and the
information in the Ardour docs.</p></div></blockquote><div></div><div>Hey I got one of those, very good laptop :) <br></div><div> <br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div>
<p>At least I can run Zynaddsubfx with 0.726 msec latency now
without xruns using a cheap Behringer usb device. ;) <br></p></div></blockquote><div>Do you mind sharing a bit more what settings and toolchain this includes?</div><div>kernel? distro? Jack? what buffersettings?</div><div><br></div><div>--</div><div>On a related note, I tested some more with the standard xanmod-rt-edge kernel on another laptop (hp something, the troubled one I mentioned earlier) under kubuntu 20.04 and it does seem this kernel behaves a bit better than the lowlatency kernel I had before. It is not a night and day difference.</div><div><br></div><div>Also, not sure if this is general knowledge, but I've had the feeling before that disabling graphical login and running X with startx improves resiliency to xruns, tried it now again and I believe it is still true.</div><div>I've got no metrics apart from counting xruns when doing some startup operations of my rig with 128 frame buffers.</div><div><br></div><div>/Robert</div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div><p>
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