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<div class="moz-cite-prefix">On 6/4/20 3:09 PM, Paul Davis wrote:<br>
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cite="mid:CAFa_cKmOnaoT9HE5Rk1aN3JP9CyxM=6PcRZg-7-f7jMW-rbakg@mail.gmail.com">
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<div style="font-family:arial,helvetica,sans-serif"
class="gmail_default">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"
class="gmail_default">However ...</div>
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<div style="font-family:arial,helvetica,sans-serif"
class="gmail_default">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"
class="gmail_default">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"
class="gmail_default"><a
href="https://manual.ardour.org/setting-up-your-system/the-right-computer-system-for-digital-audio/"
moz-do-not-send="true">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>
<p>At least I can run Zynaddsubfx with 0.726 msec latency now
without xruns using a cheap Behringer usb device. ;) <br>
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