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List: gnuradio-discuss
Subject: Issue with Polyphase Clock Sync Block
From: Muneeb Mujahid <muneeb.mujahid () aero ! org>
Date: 2022-09-09 0:28:26
Message-ID: SA0PR09MB720953DDAD0E1D2483A42D2BFB439 () SA0PR09MB7209 ! namprd09 ! prod ! outlook ! com
[Download RAW message or body]
Hello,
While working on a couple of projects, I encountered an issue where, when t=
he CPU was under heavy load, the flowgraph would start having dropped sampl=
es occur in a non-deterministic fashion. This was strange as the flowgraph =
was reading in data from a file and so it should've adjusted the speed as n=
eeded to work with the resources available. After some tests, the Polyphase=
Clock Sync was found to be causing the issue. Basically, when under high c=
pu load, the presence of the block would lead to non-deterministic behavior=
and the occasional dropping of samples. I then replaced this block with an=
M&M timing tracking block and that has seemed to resolve the issue. This w=
as in GNU Radio version 3.7.14.0. I'm not sure if this issue has been point=
ed out or addressed before but I wasn't able to find anything online about =
it.
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<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">While working on a couple of projects, I encountered an issue \
where, when the CPU was under heavy load, the flowgraph would start having dropped \
samples occur in a non-deterministic fashion. This was strange as the flowgraph was \
reading in data from a file and so it should’ve adjusted the speed as needed \
to work with the resources available. After some tests, the Polyphase Clock Sync was \
found to be causing the issue. Basically, when under high cpu load, the presence of \
the block would lead to non-deterministic behavior and the occasional dropping of \
samples. I then replaced this block with an M&M timing tracking block and that \
has seemed to resolve the issue. This was in GNU Radio version 3.7.14.0. I’m \
not sure if this issue has been pointed out or addressed before but I wasn’t \
able to find anything online about it.<o:p></o:p></p> </div>
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