<html>
<head>
<meta content="text/html; charset=windows-1252"
http-equiv="Content-Type">
</head>
<body text="#000000" bgcolor="#FFFFFF">
<br>
<br>
<div class="moz-cite-prefix">On 01/24/2016 08:03 AM, Fokke de Jong
wrote:<br>
</div>
<blockquote
cite="mid:09176166-6CF7-4DFB-885C-445C0E0F6818@gmail.com"
type="cite">
<meta http-equiv="Content-Type" content="text/html;
charset=windows-1252">
<div style="margin: 0px;" class="">Hi all,</div>
<div style="margin: 0px; min-height: 14px;" class=""><br class="">
</div>
<div style="margin: 0px;" class="">This is my first post here. I’m
note new to audio programming or linux, but I haven’t done much
in terms of combining the two. Most of my audio programming has
been on os x.</div>
<div style="margin: 0px; min-height: 14px;" class=""><br class="">
</div>
<div style="margin: 0px;" class="">Currently working on some
realtime convolution with lots of channels and low latency
requirements, but I am running into some unexpected cpu-spikes
and hope some of you might have an idea of possible causes.</div>
<div style="margin: 0px; min-height: 14px;" class=""><br class="">
</div>
<div style="margin: 0px;" class="">I’m processing 32 sample-blocks
at 48KHz but roughly every 0,6 seconds I get a large spike in
cpu usage. This cannot possibly be explained by my algorithm,
because the load should be pretty stable. <br>
<br>
[...snip...]<br>
</div>
<br>
<div style="margin: 0px;" class="">I’m running (more or less
default install, no additional services run-in) Linux Mint 17.3
with a 3.19.0-42-lowlatency kernel on a core i7-6700 with
hyperthreading/turbo disabled.</div>
<div style="margin: 0px; min-height: 14px;" class=""><br class="">
</div>
<div style="margin: 0px;" class="">I remember reading somewhere
that realtime threads cannot run more than .95s every second.
That would be very bad if it actually meant my threads are
blocked run for a period of 50ms straight…</div>
<div style="margin: 0px; min-height: 14px;" class=""><br class="">
</div>
<div style="margin: 0px; min-height: 14px;" class="">Anyone have
any thoughts on possible causes?</div>
<div style="margin: 0px; min-height: 14px;" class=""><br class="">
</div>
<div style="margin: 0px;" class="">best,</div>
<div style="margin: 0px;" class="">Fokke</div>
</blockquote>
You're running Mint :-) Lots of background bells and whistles
there, lots of things which will crop up and interfere, things you
cannot disable or turn off with absolute certainty. If you want
smooth power, you'll have to choose more carefully. My current SOP
in more detail here:<br>
<br>
<a class="moz-txt-link-freetext" href="http://lsn.ponderworthy.com/doku.php/choosing_a_linux_platform_for_live_synth">http://lsn.ponderworthy.com/doku.php/choosing_a_linux_platform_for_live_synth</a><br>
<br>
<br>
<br>
<div class="moz-signature">-- <br>
<div style="color: #993300; font-size: 0.8em; font-style: italic;">
Jonathan E. Brickman <a class="moz-txt-link-abbreviated" href="mailto:jeb@ponderworthy.com">jeb@ponderworthy.com</a> (785)233-9977<br>
Hear us at <a href="http://ponderworthy.com">http://ponderworthy.com</a>
-- CDs and MP3 <a
href="http://ponderworthy.com/ad-astra/ad-astra.html">now
available!</a><br>
Music of compassion; fire, and life!!!
</div>
</div>
</body>
</html>