<div dir="ltr"><div>I agree that a data sample is needed to properly assist (or the output of printVDIF or similar might already help too - basically a summary of what is in the headers). My initial guess is an issue with either the threadIDs or the number of channels per thread that is being placed in the VDIF header.</div><div><br></div><div>Cheers,</div><div>Adam</div></div><br><div class="gmail_quote gmail_quote_container"><div dir="ltr" class="gmail_attr">On Fri, 21 Feb 2025 at 03:03, Walter Brisken via Difx-users <<a href="mailto:difx-users@listmgr.nrao.edu">difx-users@listmgr.nrao.edu</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><u></u>
<div>
<p>Hi Jake,</p>
<p><br>
</p>
<p>It would be most useful if you could make available the .input
file and a sample of the VDIF stream (perhaps a couple to a couple
hundred MB made available through http) that you are dealing
with. The .vex file is also a useful source of info if that can
be shared.<br>
</p>
<p><br>
</p>
<p>Cheers,</p>
<p><br>
</p>
<p>Walter<br>
</p>
<p><br>
</p>
<div>On 2/20/25 05:12, Jacob Brooks via
Difx-users wrote:<br>
</div>
<blockquote type="cite">
<div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
Hi all,</div>
<div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
We're currently trying to get DiFX working with the following
setup: 4-bit, 2 channel (L + R pols), 2 threads (2 subbands),
delivered in real time via UDP. It has been working fine up
until the point where we tried adding a second thread -
single-thread VDIF has been working for us.<br>
<br>
When running in multi-threaded mode, the datastream processes
crash with the following message:<br>
<br>
'vdifmux() failed with return code -2014, likely input buffer is
too small!'<br>
<br>
I have managed to trace the problem to a check in
'getLowestFrameNumber' in vdifio/src/vdifmux.c. The inequality
check in that function:<br>
<br>
'getVDIFNumChannels(vh) != vm->inputChannelsPerThread'</div>
<div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
succeeds as the function returns a value of 2 while
'inputChannelsPerThread' has a value of 1. This happens for
every iteration so vdifmux() fails and returns a -2014 error
code.</div>
<div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
I'm not sure where to go from here and was hoping someone more
familiar with DiFX could help out. Hopefully I'm not missing
something obvious! If you need any more information I haven't
provided please do ask.</div>
<div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
<br>
</div>
<div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
Cheers,</div>
<div style="font-family:Aptos,Aptos_EmbeddedFont,Aptos_MSFontService,Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
Jake</div>
<br>
<fieldset></fieldset>
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</blockquote></div><div><br clear="all"></div><br><span class="gmail_signature_prefix">-- </span><br><div dir="ltr" class="gmail_signature"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr" style="font-size:12.8px"><div dir="ltr" style="font-size:12.8px"><div dir="ltr" style="font-size:12.8px"><div dir="ltr" style="font-size:12.8px"><div dir="ltr" style="font-size:12.8px"><div dir="ltr" style="font-size:12.8px">!=============================================================!<br><div dir="ltr" style="font-size:12.8px">Prof. Adam Deller </div></div><div style="font-size:12.8px">Centre for Astrophysics & Supercomputing </div><div dir="ltr" style="font-size:12.8px">Swinburne University of Technology <br>John St, Hawthorn VIC 3122 Australia</div><div style="font-size:12.8px">phone: +61 3 9214 5307</div><div style="font-size:12.8px">fax: +61 3 9214 8797</div><div style="font-size:12.8px">!=============================================================!</div></div></div></div></div></div></div></div></div></div></div></div></div></div></div>